<PAGE>

                                                                   EXHIBIT 99.1

                             LETTER OF TRANSMITTAL

                               US ONCOLOGY, INC.

                               Offer to Exchange
                   9 5/8% Senior Subordinated Notes due 2012
   which have been registered under the Securities Act of 1933, as amended,
               pursuant to the Prospectus, dated         , 2002,
                        for all issued and outstanding
                   9 5/8% Senior Subordinated Notes due 2012

 THE EXCHANGE OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON       ,
 2002, UNLESS THE EXCHANGE OFFER IS EXTENDED. TENDERS MAY BE WITHDRAWN PRIOR
 TO 5:00 P.M., NEW YORK CITY TIME, ON THE EXPIRATION DATE.

-------------------------------------------------------------------------------

                 The Exchange Agent for the Exchange Offer is:

                              JPMORGAN CHASE BANK

<TABLE>
 <S>                            <C>                           <C>
 By Regular or Certified Mail                                  To Confirm by Telephone or
              or                        By Facsimile:                      for
                                     (Eligible Guarantor
  Overnight Courier or Hand:         Institutions Only)             Information Call:

      JPMorgan Chase Bank            JPMorgan Chase Bank           JPMorgan Chase Bank
    2001 Bryan Street, 10th        2001 Bryan Street, 10th
             Floor                          Floor                Attention: Frank Ivins
      Dallas, Texas 75201            Dallas, Texas 75201          Phone: (214) 468-6464
    Attention: Frank Ivins         Attention: Frank Ivins
                                     Fax: (214) 468-6092
</TABLE>

  Delivery of this Letter of Transmittal to an address other than those listed
above, or transmission of instructions by facsimile other than as set forth
above, will not constitute a valid delivery of your Old Notes.

  By signing this Letter of Transmittal, you hereby acknowledge that you have
received and reviewed the Prospectus, dated      , 2002, of US Oncology, Inc.
and this Letter of Transmittal. The Prospectus, together with this Letter of
Transmittal, constitutes US Oncology, Inc.'s offer to exchange an aggregate
principal amount of up to $175,000,000 of its 9 5/8% Senior Subordinated Notes
due 2012 (the "New Notes"), which have been registered under the Securities
Act of 1933, as amended (the "Securities Act"), for a like principal amount of
our issued and outstanding 9 5/8% Senior Subordinated Notes due 2012 (the "Old
Notes"). The Old Notes were issued in an offering under Rule 144A and
Regulation S of the Securities Act that was not registered under the
Securities Act. This Exchange Offer is being extended to all holders of the
Old Notes.

  If you decide to tender your Old Notes, and we accept the Old Notes, this
will constitute a binding agreement between you and US Oncology, Inc., subject
to the terms and conditions set forth in the Prospectus and this Letter of
Transmittal. Unless you comply with the procedures described in the Prospectus
under the caption "The exchange offer--Guaranteed delivery procedures," you
must do one of the following on or prior to the expiration of the Exchange
Offer to participate in the Exchange Offer:


  . tender your Old Notes by sending the certificates for your Old Notes, in
    proper form for transfer, a properly completed and duly executed Letter
    of Transmittal, with any required signature guarantees, and all other
    documents required by this Letter of Transmittal to the Exchange Agent at
    one of the addresses listed above; or
<PAGE>

  . tender your Old Notes by using the book-entry transfer procedures
    described in the Prospectus under the caption "The exchange offer--Book-
    entry transfer," and transmitting this Letter of Transmittal, with any
    required signature guarantees, or an Agent's Message (as defined below)
    instead of this Letter of Transmittal to the Exchange Agent.


  In order for a book-entry transfer to constitute a valid tender of your Old
Notes in the Exchange Offer, the Exchange Agent must receive a confirmation of
book-entry transfer (a "Book-Entry Confirmation") of your Old Notes into the
Exchange Agent's account at The Depository Trust Company in accordance with
The Depository Trust Company's Automated Tender Offer Program prior to the
expiration of the Exchange Offer. The term "Agent's Message" means a message,
transmitted by The Depository Trust Company and received by the Exchange Agent
and forming a part of the Book-Entry Confirmation, which states that The
Depository Trust Company has received an express acknowledgment from you that
you have received and have agreed to be bound by the terms of this Letter of
Transmittal. If you use this procedure, we may enforce the Letter of
Transmittal against you.

  Delivery of documents to The Depository Trust Company's book-entry transfer
facility will not constitute delivery to the Exchange Agent.

  If you are a registered holder of Old Notes and wish to tender your Old
Notes in the Exchange Offer, but (1) the Old Notes are not immediately
available, (2) time will not permit your Old Notes or other required documents
to reach the Exchange Agent before the expiration of the Exchange Offer, or
(3) the procedure for book-entry transfer cannot be completed prior to the
expiration of the Exchange Offer, you may tender Old Notes by following the
procedures described in the Prospectus under the caption "The exchange offer--
Guaranteed delivery procedures."

  Only registered holders of Old Notes--which term, for purposes of this
Letter of Transmittal, includes any participant in The Depository Trust
Company's system whose name appears on a security position listing as the
owner of the Old Notes--are entitled to tender their Old Notes for exchange in
the Exchange Offer. If you are a beneficial owner whose Old Notes are
registered in the name of a broker, dealer, commercial bank, trust company or
other nominee and you wish to tender your Old Notes in the Exchange Offer, you
should promptly contact the person in whose name the Old Notes are registered
and instruct that person to tender on your behalf. If you wish to tender in
the Exchange Offer on your own behalf, prior to completing and executing this
Letter of Transmittal and delivering the certificates for your Old Notes, you
must either make appropriate arrangements to register ownership of the Old
Notes in your name or obtain a properly completed bond power from the person
in whose name the Old Notes are registered.

  You must complete this Letter of Transmittal if you are a registered holder
of Old Notes--which term, for purposes of this Letter of Transmittal, includes
any participant in The Depository Trust Company's system whose name appears on
a security position listing as the owner of the Old Notes--and either (1) you
wish to tender the certificates representing your Old Notes to the Exchange
Agent together with this Letter of Transmittal or (2) you wish to tender your
Old Notes by book-entry transfer to the Exchange Agent's account at The
Depository Trust Company and you elect to submit this Letter of Transmittal to
the Exchange Agent instead of an Agent's Message.

  In order to properly complete this Letter of Transmittal, you must: (1)
complete the box entitled "Description of Old Notes Tendered," (2) if
appropriate, check and complete the boxes relating to book-entry transfer and
guaranteed delivery and the boxes entitled "Special Issuance Instructions" and
"Special Delivery Instructions," (3) sign this Letter of Transmittal by
completing the box entitled "Sign Here" and (4) complete the box entitled
"Substitute Form W-9." By completing the box entitled "Description of Old
Notes Tendered" and signing below, you will have tendered your Old Notes for
exchange on the terms and conditions described in the Prospectus and this
Letter of Transmittal. You should read the detailed instructions below before
completing this Letter of Transmittal.

                                       2
<PAGE>

                    NOTE: SIGNATURES MUST BE PROVIDED BELOW
              PLEASE READ THE ACCOMPANYING INSTRUCTIONS CAREFULLY

        BOX BELOW TO BE COMPLETED BY ALL TENDERING HOLDERS OF OLD NOTES

      DESCRIPTION OF OLD NOTES TENDERED (CUSIP NO. 90338WAB9) (Rule 144A)
--------------------------------------------------------------------------------
<TABLE>
<CAPTION>
 Name and
Address of
Registered
  Holder         1            2            3
-------------------------------------------------
                          Aggregate
                          Principal    Principal
            Certificate     Amount       Amount
            Number(s)*  of Old Note(s) Tendered**
<S>         <C>         <C>            <C>
                                            -----
                                            -----
                                            -----
                                            -----
                                            -----

                                            Total:
</TABLE>
--------------------------------------------------------------------------------
 *  Need not be completed by holders who tender by book-entry transfer.
 ** Old Notes tendered by this Letter of Transmittal must be in denominations
    of $1,000 principal amount and any integral multiple thereof. Unless
    otherwise indicated in column 3, a holder will be deemed to have tendered
    ALL of the Old Notes represented by the certificate(s) listed in column 1.
    (See Instruction 4.)


   DESCRIPTION OF OLD NOTES TENDERED (CUSIP NO. USU91252AA13) (Regulation S)
--------------------------------------------------------------------------------
<TABLE>
<CAPTION>
 Name and
Address of
Registered
  Holder         1            2            3
------------------------------------------------
                          Aggregate
                          Principal    Principal
            Certificate     Amount       Amount
            Number(s)*  of Old Note(s) Tendered**
<S>         <C>         <C>            <C>
                                            -----
                                            -----
                                            -----
                                            -----
                                            -----

                                            Total:
</TABLE>
--------------------------------------------------------------------------------
 *  Need not be completed by holders who tender by book-entry transfer.
 ** Old Notes tendered by this Letter of Transmittal must be in denominations
    of $1,000 principal amount and any integral multiple thereof. Unless
    otherwise indicated in column 3, a holder will be deemed to have tendered
    ALL of the Old Notes represented by the certificate(s) listed in column 1.
    (See Instruction 4.)


                                       3
<PAGE>

                    BOXES BELOW TO BE CHECKED AS APPLICABLE

[_]Check here if the certificate(s) representing your Old Notes is being
   tendered with this Letter of Transmittal.


[_]Check here if the certificate(s) representing your Old Notes has been lost,
   destroyed or stolen and you require assistance in obtaining a new
   certificate(s).


  Certificate Number(s) ______________________________________________________
  Principal Amount(s) Represented ____________________________________________

  You must contact the Exchange Agent to obtain instructions for replacing
  lost, destroyed or stolen certificate(s) representing Old Notes. (See
  Instruction 12.)


                                              SPECIAL DELIVERY INSTRUCTIONS
    SPECIAL ISSUANCE INSTRUCTIONS             (See Instructions 1, 5 and 6)
    (See Instructions 1, 5 and 6)


                                           To be completed ONLY if New Notes
 To be completed ONLY if New Notes         or Old Notes not tendered or
 or Old Notes not tendered or              exchanged are to be delivered to
 exchanged are to be issued in the         someone other than the registered
 name of someone other than the            holder of the Old Notes whose
 registered holder of the Old Notes        name(s) appear(s) below or to the
 whose name(s) appear below.               registered holder at an address
                                           other than that shown below.


 [_]Old Note(s) to:
 [_]New Note(s) to:                        [_]Old Note(s) to:
                                           [_]New Note(s) to:


 Name ______________________________
           (Please Print)                  Name ______________________________
                                                     (Please Print)


 Address ___________________________
                                           Address ___________________________


 -----------------------------------
             (Zip Code)                    -----------------------------------
                                                       (Zip Code)


               (   )    -
 Telephone Number __________________
                                                         (   )    -
                                           Telephone Number __________________


 -----------------------------------
    (Tax Identification or Social          -----------------------------------
          Security Number)                    (Tax Identification or Social
         (See Instruction 9)                        Security Number)
                                                   (See Instruction 9)



[_]Check here and enclose a photocopy of the Notice of Guaranteed Delivery if
   tendered Old Notes are being delivered under a Notice of Guaranteed
   Delivery previously sent to the Exchange Agent and complete the following:

  Name(s) of Registered Holder(s) ____________________________________________
  Window Ticket Number (if any) ______________________________________________
  Date of Execution of Notice of Guaranteed Delivery _________________________
  Name of Institution Which Guaranteed Delivery ______________________________
    If delivered by Book-Entry Transfer, complete the following:

  Name of Tendering Institution ______________________________________________
  Account Number _____________________________________________________________
  Transaction Code Number ____________________________________________________


                                       4
<PAGE>

            BOXES BELOW TO BE CHECKED BY ELIGIBLE INSTITUTIONS ONLY

[_]Check here if tendered Old Notes are being delivered by book-entry transfer
   to the Exchange Agent's account at The Depository Trust Company and
   complete the following:

  Name of Tendering Institution ______________________________________________
  Account Number _____________________________________________________________
  Transaction Code Number ____________________________________________________


[_]Check here if Old Notes that are not tendered or not exchanged are to be
   returned by crediting The Depository Trust Company account number indicated
   above.


                                       5
<PAGE>

Ladies and Gentlemen:

  Upon the terms and subject to the conditions of the Exchange Offer, as
described in the Prospectus and this Letter of Transmittal, I hereby tender to
US Oncology, Inc. the aggregate principal amount of Old Notes described above
in the box entitled "Description of Old Notes Tendered" in exchange for a like
principal amount of New Notes with the same maturity date which have been
registered under the Securities Act.

  Subject to and effective upon the acceptance for exchange of all or any
portion of the Old Notes tendered by this Letter of Transmittal in accordance
with the terms and conditions of the Exchange Offer--including, if the Exchange
Offer is extended or amended, the terms and conditions of any extension or
amendment--I hereby sell, assign and transfer to, or upon the order of, US
Oncology, Inc. all right, title and interest in and to the Old Notes tendered
by this Letter of Transmittal. I hereby irrevocably constitute and appoint the
Exchange Agent as my agent and attorney-in-fact--with full knowledge that the
Exchange Agent is also acting as the agent of US Oncology, Inc. in connection
with the Exchange Offer--with respect to the tendered Old Notes, with full
power of substitution, such power of attorney being deemed to be an irrevocable
power coupled with an interest, subject only to the right of withdrawal
described in the Prospectus, to (1) deliver certificates for the tendered Old
Notes to US Oncology, Inc. together with all accompanying evidences of transfer
and authenticity to, or upon the order of, US Oncology, Inc., upon receipt by
the Exchange Agent, as my agent, of the New Notes to be issued in exchange for
the tendered Old Notes, (2) present certificates for the tendered Old Notes for
transfer, and to transfer the tendered Old Notes on the books of US Oncology,
Inc., and (3) receive for the account of US Oncology, Inc. all benefits and
otherwise exercise all rights of ownership of the tendered Old Notes, all in
accordance with the terms and conditions of the Exchange Offer.

  I hereby represent and warrant that I have full power and authority to
tender, sell, assign and transfer the Old Notes tendered by this Letter of
Transmittal and that, when the tendered Old Notes are accepted for exchange, US
Oncology, Inc. will acquire good, marketable and unencumbered title to the
tendered Old Notes, free and clear of all liens, restrictions, charges and
encumbrances, and that the tendered Old Notes are not subject to any adverse
claims or proxies. I will, upon request, execute and deliver any additional
documents deemed by US Oncology, Inc. or the Exchange Agent to be necessary or
desirable to complete the exchange, sale, assignment and transfer of the Old
Notes tendered by this Letter of Transmittal, and I will comply with my
obligations, if any, under the Registration Rights Agreement, dated as of
February 1, 2002 (the "Registration Rights Agreement"), between US Oncology,
Inc. and UBS Warburg LLC, Deutsche Banc Alex. Brown Inc. and First Union
Securities, Inc. I have read and I agree to all of the terms of the Exchange
Offer.

  The name(s) and address(es) of the registered holder(s)--which term, for
purposes of this Letter of Transmittal, includes any participant in The
Depository Trust Company's system whose name appears on a security position
listing as the holder of the Old Notes--of the Old Notes tendered by this
Letter of Transmittal are printed above as they appear on the certificate(s)
representing the Old Notes. The certificate number(s) and the Old Notes that I
wish to tender are indicated in the appropriate boxes above.

  Unless I have otherwise indicated by completing the box entitled "Special
Issuance Instructions" above, I hereby direct that the New Notes be issued in
the name(s) of the undersigned or, in the case of a book-entry transfer of Old
Notes, that the New Notes be credited to the account indicated above maintained
with The Depository Trust Company. Similarly, unless I have otherwise indicated
by completing the box entitled "Special Delivery Instructions," I hereby direct
that the New Notes be delivered to the address shown below my signature.

                                       6
<PAGE>

  If I have (1) tendered any Old Notes that are not exchanged in the Exchange
Offer for any reason or (2) submitted certificates for more Old Notes than I
wish to tender, unless I have otherwise indicated by completing the boxes
entitled "Special Issuance Instructions" or "Special Delivery Instructions," I
hereby direct that certificates for any Old Notes that are not tendered or not
exchanged should be issued in the name of the undersigned, if applicable, and
delivered to the address shown below my signature or, in the case of a book-
entry transfer of Old Notes, that Old Notes that are not tendered or not
exchanged be credited to the account indicated above maintained with The
Depository Trust Company, in each case, at US Oncology, Inc.'s expense,
promptly following the expiration or termination of the Exchange Offer.

  I understand that if I decide to tender Old Notes, and US Oncology, Inc.
accepts the Old Notes for exchange, this will constitute a binding agreement
between me and US Oncology, Inc., subject to the terms and conditions set forth
in the Prospectus and this Letter of Transmittal.

  I also recognize that, under certain circumstances described in the
Prospectus under the caption "The exchange offer--Conditions to the exchange
offer," US Oncology, Inc. may not be required to accept for exchange any of the
Old Notes tendered by this Letter of Transmittal.

  By tendering Old Notes and executing this Letter of Transmittal, or
delivering an Agent's Message instead of this Letter of Transmittal, I hereby
represent and agree that: (1) any New Notes I receive in the Exchange Offer are
being acquired by me in the ordinary course of my business; (2) at the time of
the commencement of the Exchange Offer, neither I nor, to my knowledge, anyone
receiving New Notes from me, has any arrangement or understanding with any
person to participate in the distribution (as defined in the Securities Act) of
the New Notes in violation of the Securities Act; (3) I am not an "affiliate"
(as defined in Rule 405 under the Securities Act) of US Oncology, Inc.; (4) if
I am not a Participating Broker-Dealer (as defined below), that I am not
engaged in, and do not intend to engage in, the distribution of the New Notes;
and (5) if I am a Participating Broker-Dealer, that I will receive the New
Notes for my own account in exchange for Old Notes that I acquired as a result
of my market-making or other trading activities and that I will deliver a
prospectus meeting the requirements of the Securities Act in connection with
any resale of the New Notes I receive. As used in this Letter of Transmittal, a
"Participating Broker-Dealer" is a broker-dealer that receives New Notes for
its own account in exchange for Old Notes that it acquired as a result of
market-making or other trading activities. If I am a Participating Broker-
Dealer, by making the representation set forth above and delivering a
prospectus in connection with any resale transaction involving the New Notes, I
understand that I will not be deemed to have admitted that I am an
"underwriter" within the meaning of the Securities Act.

  US Oncology, Inc. has agreed, subject to the terms of the Registration Rights
Agreement, that for a period of not more than 180 days after the expiration or
termination of the Exchange Offer, it will make the Prospectus, as amended or
supplemented from time to time, available to any Participating Broker-Dealer
for use in connection with resales of the New Notes. Each Participating Broker-
Dealer, by tendering Old Notes and executing this Letter of Transmittal, or
delivering an Agent's Message instead of this Letter of Transmittal, agrees
that, upon receipt of notice from US Oncology, Inc. of the occurrence of any
event or the discovery of any fact which makes any statement contained or
incorporated by reference in the Prospectus untrue in any material respect or
which causes the Prospectus to omit to state a material fact necessary in order
to make the statements contained or incorporated by reference in the
Prospectus, in light of the circumstances under which they were made, not
misleading, the Participating Broker-Dealer will suspend the sale of New Notes
under the Prospectus. Each Participating Broker-Dealer further agrees that,
upon receipt of a notice from US Oncology, Inc. to suspend the sale of New
Notes as provided above, the Participating Broker-Dealer will suspend resales
of the New Notes until (1) US Oncology, Inc. has amended or supplemented the
Prospectus to correct the misstatement or omission and has furnished copies of
the amended or

                                       7
<PAGE>

supplemented Prospectus to the Participating Broker-Dealer or (2) US Oncology,
Inc. has given notice that the sale of the New Notes may be resumed, as the
case may be. If US Oncology, Inc. gives notice to suspend the sale of the New
Notes as provided above, it will extend the period referred to above during
which Participating Broker-Dealers are entitled to use the Prospectus in
connection with the resale of New Notes by the number of days during the period
from and including the date of the giving of such notice to and including the
date when Participating Broker-Dealers receive copies of the supplemented or
amended Prospectus necessary to permit resales of the New Notes or to and
including the date on which US Oncology, Inc. has given notice that the sale of
New Notes may be resumed, as the case may be.

  As a result, a Participating Broker-Dealer who intends to use the Prospectus
in connection with resales of New Notes received in exchange for Old Notes in
the Exchange Offer must notify US Oncology, Inc., on or prior to the expiration
of the Exchange Offer, that it is a Participating Broker-Dealer. Participating
Broker-Dealers must send the required written notice to US Oncology, Inc.'s
executive offices located at 16825 Northchase Drive, Suite 1300, Houston, Texas
77060, Attention: General Counsel, and this notice must be received by US
Oncology, Inc. at or prior to the expiration of the Exchange Offer.

  Interest on the New Notes will accrue (1) from the later of (a) the last date
to which interest was paid on the Old Notes surrendered in exchange for the New
Notes or (b) if the Old Notes are surrendered for exchange on a date in a
period which includes the record date for an interest payment date to occur on
or after the date of the exchange and as to which interest will be paid, the
date to which interest will be paid on such interest payment date or (2) if no
interest has been paid on the Old Notes, from February 1, 2002.

  All authority conferred in or agreed to be conferred in this Letter of
Transmittal will survive my death or incapacity, and any obligation of mine
under this Letter of Transmittal will be binding upon my heirs, executors,
administrators, personal representatives, trustees in bankruptcy, legal
representatives, successors and assigns. Except as stated in the Prospectus,
this tender is irrevocable.

                                       8
<PAGE>

                                   SIGN HERE
                         (SEE INSTRUCTIONS 2, 5 AND 6)
                  (PLEASE COMPLETE SUBSTITUTE FORM W-9 BELOW)
      (NOTE: SIGNATURE(S) MUST BE GUARANTEED IF REQUIRED BY INSTRUCTION 2)

  This Letter of Transmittal must be signed by (1) the registered holder(s)--
which term, for purposes of this Letter of Transmittal, includes any
participant in The Depository Trust Company's system whose name appears on a
security position listing as the holder of the Old Notes--exactly as the
name(s) of the registered holder(s) appear(s) on the certificate(s) for the Old
Notes tendered or on the register of holders maintained by US Oncology, Inc.,
or (2) by any person(s) authorized to become the registered holder(s) by
endorsements and documents transmitted with this Letter of Transmittal--
including any opinions of counsel, certifications and other information as may
be required by US Oncology, Inc. for the Old Notes to comply with the
restrictions on transfer applicable to the Old Notes. If the signature below is
by a trustee, executor, administrator, guardian, attorney-in-fact, officer of a
corporation or another acting in a similar fiduciary or representative
capacity, please set forth the signer's full title. See Instruction 5.

X ______________________________________________________________________________

X ______________________________________________________________________________
                         Signature(s) of Noteholder(s)

Dated: __________________________________________________________________ , 2002
Name(s) ________________________________________________________________________
                                 (Please Print)

--------------------------------------------------------------------------------
Capacity _______________________________________________________________________
Address ________________________________________________________________________
--------------------------------------------------------------------------------
                                   (Zip Code)

Tax Identification or Social Security No. ______________________________________
                                             (See Instruction 9)
Area Code and Telephone No. ____________________________________________________

                            SIGNATURE(S) GUARANTEED
                        (See Instruction 2, if required)

Eligible Guarantor Institution _________________________________________________
Official Signature _____________________________________________________________
Dated: __________________________________________________________________ , 2002

                                       9
<PAGE>

             TO BE COMPLETED BY ALL TENDERING HOLDERS OF SECURITIES

                       PAYOR'S NAME: JPMORGAN CHASE BANK

--------------------------------------------------------------------------------
                        PART 1--PLEASE PROVIDE YOUR   TIN
                        TIN IN THE BOX AT THE RIGHT
                        AND CERTIFY BY SIGNING AND        ------------------
                        DATING BELOW

 SUBSTITUTE
 FORM W-9
                                                         (Social Security
                                                            Number or
                                                     Employer Identification
                                                             Number)

 --------------------

 Name                  --------------------------------------------------------
                        PART 2--FOR PAYEES EXEMPT FROM BACKUP WITHHOLDING
                        (SEE INSTRUCTIONS)


 --------------------

                       --------------------------------------------------------
 Address (Number and Street)

                        PART 3--CERTIFICATION--UNDER PENALTIES OF PERJURY, I
                        CERTIFY THAT (1) The number shown on this form is my
                        correct TIN (or I am waiting for a number to be
                        issued to me), (2) I am not subject to backup
                        withholding because: (a) I am exempt from backup
                        withholding, or (b) I have not been notified by the
                        Internal Revenue Service (the "IRS") that I am
                        subject to backup withholding as a result of a
                        failure to report all interest or dividends or (c)
                        the IRS has notified me that I am no longer subject
                        to backup withholding, and (3) I am a U.S. person
                        (including a U.S. resident alien).

 --------------------
 City, State and Zip Code

 Department of the
 Treasury


 Internal Revenue       CERTIFICATION INSTRUCTIONS--You must cross out item
 Service                (2) in Part 3 above if you have been notified by the
                        IRS that you are currently subject to backup
                        withholding because of underreporting interest or
                        dividends on your tax return. However, if after
                        being notified by the IRS that you are subject to
                        backup withholding you receive another notification
                        from the IRS stating that you are no longer subject
                        to backup withholding, do not cross out item (2) in
                        Part 3.

 Payor's Request for
 Taxpayer
 Identification
 Number ("TIN") and
 Certification
                        SIGNATURE _______________________________ DATE , 2002


 YOU MUST COMPLETE THE FOLLOWING CERTIFICATE IF YOU WROTE "APPLIED FOR" IN PART
                          1 OF THE SUBSTITUTE FORM W-9

             CERTIFICATE OF AWAITING TAXPAYER IDENTIFICATION NUMBER

    I certify under penalties of perjury that a taxpayer identification
 number has not been issued to me, and that I mailed or delivered an
 application to receive a taxpayer identification number to the appropriate
 Internal Revenue Service Center or Social Security Administration Office
 (or I intend to mail or deliver an application in the near future). I
 understand that if I do not provide a taxpayer identification number to the
 payor within 60 days, the payor will be required to withhold 30 percent of
 all reportable payments made to me thereafter until I provide a taxpayer
 identification number.

 -------------------------------------     _________________________________
              Signature                                 Date


NOTE: FAILURE TO COMPLETE AND RETURN THIS FORM MAY RESULT IN BACKUP WITHHOLDING
      OF ANY REPORTABLE PAYMENTS MADE TO YOU IN RESPECT OF THE REGISTERED NOTES
      DELIVERABLE TO YOU PURSUANT TO THE EXCHANGE OFFER. PLEASE REVIEW THE
      ENCLOSED INSTRUCTIONS AND GUIDELINES FOR CERTIFICATION OF TAXPAYER
      IDENTIFICATION NUMBER ON SUBSTITUTE FORM W-9 FOR ADDITIONAL DETAILS.

                                       10
<PAGE>

                                  INSTRUCTIONS

         Forming Part of the Terms and Conditions of the Exchange Offer

  1. DELIVERY OF LETTER OF TRANSMITTAL AND CERTIFICATES; GUARANTEED DELIVERY
PROCEDURES. You must complete this Letter of Transmittal if you are a holder of
Old Notes--which term, for purposes of this Letter of Transmittal, includes any
participant in The Depository Trust Company's system whose name appears on a
security position listing as the holder of the Old Notes--and either (1) you
wish to tender the certificates representing your Old Notes to the Exchange
Agent together with this Letter of Transmittal or (2) you wish to tender your
Old Notes by book-entry transfer to the Exchange Agent's account at The
Depository Trust Company and you elect to submit this Letter of Transmittal to
the Exchange Agent instead of an Agent's Message. In order to constitute a
valid tender of your Old Notes, unless you comply with the procedures for
Guaranteed Delivery described below, the Exchange Agent must receive the
following documents at one of the addresses listed above on or prior to the
expiration of the Exchange Offer: (1) certificates for the Old Notes, in proper
form for transfer, or Book-Entry Confirmation of transfer of the Old Notes into
the Exchange Agent's account at The Depository Trust Company in accordance with
The Depository Trust Company's Automated Tender Offer Program, (2) a properly
completed and duly executed Letter of Transmittal, with any required signature
guarantees, or, in the case of a Book-Entry Confirmation, an Agent's Message
instead of this Letter of Transmittal, and (3) all other documents required by
this Letter of Transmittal. Old Notes tendered in the Exchange Offer must be in
denominations of $1,000 principal amount and any integral multiple thereof.

  If you are a holder of the Old Notes and wish to tender your Old Notes, but
(1) the certificates for Old Notes are not immediately available, (2) time will
not permit your certificates for Old Notes or other required documents to reach
the Exchange Agent before the expiration of the Exchange Offer, or (3) the
procedure for book-entry transfer cannot be completed prior to the expiration
of the Exchange Offer, you may effect a tender if: (1) the tender is made
through an Eligible Guarantor Institution (as defined below); (2) prior to the
expiration of the Exchange Offer, the Exchange Agent receives from an Eligible
Guarantor Institution a properly completed and duly executed Notice of
Guaranteed Delivery, substantially in the form we have provided, setting forth
your name and address and the amount of Old Notes you are tendering and stating
that the tender is being made by Notice of Guaranteed Delivery; and (3) the
Exchange Agent receives within three New York Stock Exchange, Inc. ("NYSE")
trading days after the date of execution of the Notice of Guaranteed Delivery:
(a) the certificates for all physically tendered Old Notes, in proper form for
transfer, or a Book-Entry Confirmation of transfer of the Old Notes into the
Exchange Agent's account at The Depository Trust Company, as the case may be,
(b) a properly completed and duly executed Letter of Transmittal, with any
required signature guarantees, or, in the case of a Book-Entry Confirmation, an
Agent's Message instead of the Letter of Transmittal, and (c) all other
documents required by the Letter of Transmittal. The Notice of Guaranteed
Delivery may be sent by overnight courier, registered or certified mail or
facsimile transmission and must include a guarantee by an Eligible Guarantor
Institution in the form set forth in the Notice.

  The method of delivery of certificates for Old Notes, Letters of Transmittal,
Agent's Messages and all other required documents is at your election. If you
deliver your Old Notes by mail, we recommend registered mail, properly insured,
with return receipt requested. In all cases, you should allow sufficient time
to assure timely delivery. Do not send certificates for Old Notes, Letters of
Transmittal, Agent's Messages or other required documents to US Oncology, Inc.

  US Oncology, Inc. will not accept any alternative, conditional or contingent
tenders. Each tendering holder, by execution of this Letter of Transmittal or
delivery of an Agent's Message instead of the Letter of Transmittal, waives any
right to receive any notice of the acceptance of such tender.

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<PAGE>

  2. GUARANTEE OF SIGNATURES. No signature guarantee on this Letter of
Transmittal is required if:

  (a)  this Letter of Transmittal is signed by the registered holder--which
       term, for purposes of this Letter of Transmittal, includes any
       participant in The Depository Trust Company's system whose name appears
       on a security position listing as the owner of the Old Notes--of Old
       Notes tendered with this Letter of Transmittal, unless such holder(s)
       has completed either the box entitled "Special Issuance Instructions"
       or the box entitled "Special Delivery Instructions" above, or

  (b)the Old Notes are tendered for the account of a firm that is an Eligible
Guarantor Institution.

  In all other cases, an Eligible Guarantor Institution must guarantee the
signature(s) on this Letter of Transmittal. See Instruction 5.

  An "Eligible Guarantor Institution" (as defined in Rule 17Ad-15 promulgated
under the Securities Exchange Act of 1934, as amended (the "Exchange Act"))
means:

    -  Banks (as defined in Section 3(a) of the Federal Deposit Insurance
       Act);

    -  Brokers, dealers, municipal securities dealers, municipal securities
       brokers, government securities dealers and government securities
       brokers (as defined in the Exchange Act);

    -  Credit unions (as defined in Section 19B(1)(A) of the Federal Reserve
       Act);

    -  National securities exchanges, registered securities associations and
       clearing agencies (as these terms are defined in the Exchange Act);
       and

    -  Savings associations (as defined in Section 3(b) of the Federal
       Deposit Insurance Act).

  3. INADEQUATE SPACE. If the space provided in the box captioned "Description
of Old Notes Tendered" is inadequate, the certificate number(s) and/or the
principal amount of Old Notes and any other required information should be
listed on a separate signed schedule which is attached to this Letter of
Transmittal.

  4. PARTIAL TENDERS AND WITHDRAWAL RIGHTS. Tenders of Old Notes will be
accepted only in denominations of $1,000 principal amount and integral
multiples thereof. If you are tendering less than all of the Old Notes
evidenced by any certificate you are submitting, please fill in the principal
amount of Old Notes which are to be tendered in column 3 ("Principal Amount of
Old Notes Tendered") of the box entitled "Description of Old Notes Tendered."
In that case, unless you have otherwise indicated by completing the boxes
entitled "Special Issuance Instructions" or "Special Delivery Instructions",
new certificate(s) for the remainder of the Old Notes that were evidenced by
your old certificate(s) will be sent to the registered holder of the Old
Notes, promptly after the expiration of the Exchange Offer. All Old Notes
represented by certificates delivered to the Exchange Agent will be deemed to
have been tendered unless otherwise indicated.

  Except as otherwise provided in this Letter of Transmittal, tenders of Old
Notes may be withdrawn at any time on or prior to the expiration of the
Exchange Offer. For a withdrawal to be effective, a written notice of
withdrawal must be received by the Exchange Agent prior to the expiration of
the Exchange Offer at one of the addresses listed above. Any notice of
withdrawal must specify the name of the person who tendered the Old Notes to
be withdrawn, identify the Old Notes to be withdrawn, including the principal
amount of the Old Notes, and, where certificates for Old Notes have been
transmitted, specify the name in which the Old Notes are registered, if
different from that of the withdrawing holder. If certificates for Old Notes
have been delivered or otherwise identified to the Exchange Agent, then, prior
to the release of the certificates, the withdrawing holder must also submit
the serial numbers of the particular certificates to be withdrawn and a signed
notice of withdrawal with signatures guaranteed by an Eligible Guarantor
Institution unless the holder is an Eligible Guarantor

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<PAGE>

Institution. If Old Notes have been tendered using the procedure for book-entry
transfer described in the Prospectus under the caption "The exchange offer--
Book-entry transfer," any notice of withdrawal must specify the name and number
of the account at The Depository Trust Company to be credited with the
withdrawn Old Notes and otherwise comply with the procedures of the book-entry
transfer facility. All questions as to the validity, form and eligibility--
including time of receipt--of these notices will be determined by US Oncology,
Inc. Any such determination will be final and binding. Any Old Notes so
withdrawn will be deemed not to have been validly tendered for exchange for
purposes of the Exchange Offer. Any Old Notes which have been tendered for
exchange but which are not exchanged for any reason will be returned to the
registered holder without cost to that holder as soon as practicable after
withdrawal, non-acceptance of tender or termination of the Exchange Offer. In
the case of Old Notes tendered using the procedure for book-entry transfer
described in the Prospectus under the caption "The exchange offer--Book-entry
transfer," only withdrawn or unaccepted Old Notes will be credited to the
tendering holder's account with The Depository Trust Company. Properly
withdrawn Old Notes may be retendered at any time on or prior to the expiration
of the Exchange Offer by following one of the procedures described in the
Prospectus under the caption "The exchange offer--Procedures for tendering old
notes."

  5. SIGNATURES ON LETTER OF TRANSMITTAL, ASSIGNMENTS AND ENDORSEMENTS. If this
Letter of Transmittal is signed by the registered holder(s) of the Old Notes
tendered hereby, the signature(s) must correspond exactly with the name(s) as
written on the face of the certificate(s) without alteration, enlargement or
any change whatsoever.

  If any of the Old Notes tendered hereby are registered in the name of two or
more joint owners, all such owners must sign this Letter of Transmittal.

  If any tendered Old Notes are registered in different name(s) on several
certificates, it will be necessary to complete, sign and submit as many
separate Letters of Transmittal as there are different registered holders.

  When this Letter of Transmittal is signed by the registered holder(s) of the
Old Notes listed and transmitted by this Letter of Transmittal, no
endorsement(s) of certificate(s) or separate bond power(s) are required unless
New Notes are to be issued in the name of a person other than the registered
holder(s). Signature(s) on the certificate(s) or bond power(s) must be
guaranteed by an Eligible Guarantor Institution.

  If a person or persons other than the registered holder(s) of Old Notes signs
the Letter of Transmittal, certificates for the Old Notes must be endorsed or
accompanied by appropriate bond powers, signed exactly as the name or names of
the registered holder(s) that appears on the certificates for the Old Notes and
also must be accompanied by any opinions of counsel, certifications and other
information as US Oncology, Inc. may require in accordance with the
restrictions on transfer applicable to the Old Notes. Signatures on
certificates or bond powers must be guaranteed by an Eligible Guarantor
Institution.

  If you are a trustee, executor, administrator, guardian, attorney-in-fact,
officer of a corporation, or act in a similar fiduciary or representative
capacity, and wish to sign this Letter of Transmittal or any certificates for
Old Notes or bond powers, you must indicate your status when signing. If you
are acting in any of these capacities, you must submit proper evidence
satisfactory to us of your authority to so act unless we waive this
requirement.

  6. SPECIAL ISSUANCE AND DELIVERY INSTRUCTIONS. If New Notes are to be issued
in the name of a person other than the signer of this Letter of Transmittal, or
if New Notes are to be delivered to someone other than the signer of this
Letter of Transmittal or to an address other than that shown above, the
appropriate boxes on this Letter of Transmittal should be completed.
Certificates

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<PAGE>

for Old Notes not exchanged will be returned by mail or, if tendered by book-
entry transfer, by crediting the account indicated above maintained with The
Depository Trust Company. See Instruction 4.

  7. IRREGULARITIES. All questions as to the validity, form, eligibility--
including time of receipt--and acceptance of Old Notes tendered for exchange
will be determined by US Oncology, Inc. in its sole discretion. Our
determination will be final and binding. We reserve the absolute right to
reject any and all tenders of Old Notes improperly tendered or to not accept
any Old Notes, the acceptance of which might be unlawful as determined by us or
our counsel. We also reserve the absolute right to waive any defects or
irregularities or conditions of the Exchange Offer as to any Old Notes either
before or after the expiration of the Exchange Offer--including the right to
waive the ineligibility of any holder who seeks to tender Old Notes in the
Exchange Offer. Our interpretation of the terms and conditions of the Exchange
Offer as to any particular Old Notes either before or after the expiration of
the Exchange Offer--including the terms and conditions of the Letter of
Transmittal and the accompanying instructions--will be final and binding.
Unless waived, any defects or irregularities in connection with tenders of Old
Notes for exchange must be cured within a reasonable period of time, as
determined by us. Neither we, the Exchange Agent nor any other person has any
duty to give notification of any defect or irregularity with respect to any
tender of Old Notes for exchange, nor will we have any liability for failure to
give such notification.

  8. QUESTIONS, REQUESTS FOR ASSISTANCE AND ADDITIONAL COPIES. Questions and
requests for assistance may be directed to the Exchange Agent at the addresses
and telephone number listed on the front of this Letter of Transmittal.
Additional copies of the Prospectus, this Letter of Transmittal or the Notice
of Guaranteed Delivery may be obtained from US Oncology, Inc., Attention: B.
Scott Aitken, 16825 Northchase Drive, Suite 1300, Houston, Texas 77060,
Telephone: (832) 601-6178, or from your broker, dealer, commercial bank, trust
company or other nominee.

  9. TAXPAYER IDENTIFICATION NUMBER AND BACKUP WITHHOLDING. Federal income tax
law generally requires that a tendering holder whose Old Notes are accepted for
exchange must provide the Exchange Agent (as payor) with such holder's correct
Taxpayer Identification Number (a "TIN"), which, in the case of a holder who is
an individual, is such holder's social security number. If the Exchange Agent
is not provided with the correct TIN or an adequate basis for an exemption,
such holder may be subject to a $50 penalty imposed by the Internal Revenue
Service and backup withholding in an amount equal to 31% of the amount of any
reportable payments made after the exchange to such tendering holder. If
withholding results in an overpayment of taxes, a refund may be obtained.

  To prevent backup withholding, each tendering holder must provide such
holder's correct TIN by completing the "Substitute Form W-9" set forth herein,
certifying that the TIN provided is correct (or that such Holder is awaiting a
TIN) and that (i) the holder is exempt from backup withholding, (ii) the holder
has not been notified by the Internal Revenue Service that such holder is
subject to backup withholding as a result of a failure to report all interest
or dividends or (iii) the Internal Revenue Service has notified the holder that
such holder is no longer subject to backup withholding and that the holder is a
U.S. person (including a U.S. resident alien).

  Exempt holders (including, among others, all corporations and certain foreign
individuals) are not subject to these backup withholding and reporting
requirements. To prevent possible erroneous backup withholding, an exempt
Holder should write "Exempt" in Part 2 of Substitute Form W-9. See the enclosed
Guidelines for Certification of Taxpayer Identification Number on Substitute
Form W-9 (the "W-9 Guidelines") for additional instructions. In order for a
nonresident alien or foreign entity to qualify as exempt, such person must
submit a completed applicable Form W-8, signed under penalty of perjury
attesting to such exempt status. Such form may be obtained from the Exchange
Agent.

  If the Old Notes are held in more than one name or are not in the name of the
actual owner, consult the W-9 Guidelines for information on which TIN to
report.

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<PAGE>

  If the holder does not have a TIN, such holder should consult the W-9
Guidelines for instructions on applying for a TIN, write "Applied For" in the
space for the TIN in Part 1 of the Substitute Form W-9, and sign and date the
Substitute Form W-9 and the Certificate of Awaiting Taxpayer Identification
Number set forth herein. If the holder does not provide such holder's TIN to
the Exchange Agent within 60 days, backup withholding will begin and continue
until such holder furnishes such holder's TIN to the Exchange Agent. Note:
Writing "Applied For" on the Substitute Form W-9 means that the holder has
already applied for a TIN or that the holder intends to apply for one in the
near future.

  10. WAIVER OF CONDITIONS. US Oncology, Inc.'s obligation to complete the
Exchange Offer is subject to the conditions described in the Prospectus under
the caption "The Exchange Offer--Conditions to the Exchange Offer." These
conditions are for our benefit only and we may assert them regardless of the
circumstances giving rise to any condition. We may also waive any condition in
whole or in part at any time in our sole discretion. Our failure at any time to
exercise any of the foregoing rights will not constitute a waiver of that right
and each right is an ongoing right that we may assert at any time.

  11. NO CONDITIONAL TENDERS. No alternative, conditional or contingent tenders
will be accepted. All tendering holders of Old Notes, by execution of this
Letter of Transmittal, waive any right to receive notice of the acceptance of
Old Notes for exchange.

  12. LOST, DESTROYED OR STOLEN CERTIFICATES. If any certificate(s)
representing Old Notes have been lost, destroyed or stolen, the holder should
check the box above regarding lost, destroyed or stolen certificates and
promptly notify the Exchange Agent. The holder will then be instructed as to
the steps that must be taken in order to replace the certificate(s). This
Letter of Transmittal and related documents cannot be processed until the
procedures for replacing lost, destroyed or stolen certificate(s) have been
followed.

  13. TRANSFER TAXES. US Oncology, Inc. will pay all transfer taxes, if any,
applicable to the transfer of Old Notes to it or its order pursuant to the
Exchange Offer. If, however, New Notes and/or substitute Old Notes not
exchanged are to be delivered to, or are to be registered or issued in the name
of, any person other than the registered holder of the Old Notes tendered
hereby, or if tendered Old Notes are registered in the name of any person other
than the person signing this Letter, or if a transfer tax is imposed for any
reason other than the transfer of Old Notes to US Oncology, Inc. or its order
pursuant to the Exchange Offer, the amount of any such transfer taxes (whether
imposed on the registered holder or any other persons) will be payable by the
tendering holder. If satisfactory evidence of payment of such taxes or
exemption therefrom is not submitted herewith, the amount of such transfer
taxes will be billed directly to such tendering holder. Except as provided in
this Instruction 13, it will not be necessary for transfer tax stamps to be
affixed to the Old Notes specified in this Letter of Transmittal.

IMPORTANT:  Unless you comply with the Guaranteed Delivery Procedures described
            above, this Letter of Transmittal (or a facsimile of this Letter of
            Transmittal), or, in the case of Old Notes tendered by book-entry
            transfer to the Exchange Agent's account at The Depository Trust
            Company, an Agent's Message instead of this Letter of Transmittal,
            and all other required documents must be received by the Exchange
            Agent on or prior to the expiration of the Exchange Offer.

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