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                                                                   EXHIBIT 99.5

                               US ONCOLOGY, INC.

                            IS OFFERING TO EXCHANGE
                                      its
                   9 5/8% Senior Subordinated Notes due 2012
              pursuant to its Prospectus, dated           , 2002,
                        for all issued and outstanding
                   9 5/8% Senior Subordinated Notes due 2012

To Our Clients:

  Enclosed for your consideration is a prospectus, dated             , 2002
(the "Prospectus"), and the related Letter of Transmittal (the "Letter of
Transmittal") relating to the offer (the "Exchange Offer") of US Oncology,
Inc. ("USON") 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"), the
issuance of which has been registered under the Securities Act of 1933, as
amended (the "Securities Act"), for a like principal amount of its issued and
outstanding 9 5/8% Senior Subordinated Notes due 2012 (the "Old Notes"). The
Old Notes were issued in offerings under Rule 144A and Regulation S of the
Securities Act that were not registered under the Securities Act. The Exchange
Offer is being extended to all holders of the Old Notes in order to satisfy
certain obligations of USON contained in the Registration Rights Agreement,
dated as of February 1, 2002, by and among USON and UBS Warburg LLC, Deutsche
Banc Alex. Brown Inc. and First Union Securities, Inc. The New Notes are
substantially identical to the Old Notes, except that the transfer
restrictions and registration rights applicable to the Old Notes do not apply
to the New Notes.

  These materials are being forwarded to you as the beneficial owner of the
Old Notes held by us for your account but not registered in your name. A
tender of such Old Notes may only be made by us as the holder of record and
pursuant to your instructions.

  Accordingly, we request instructions as to whether you wish us to tender on
your behalf the Old Notes held by us for your account, pursuant to the terms
and conditions set forth in the enclosed Prospectus and Letter of Transmittal.

  Your instructions should be forwarded to us as promptly as possible in order
to permit us to tender the Old Notes on your behalf in accordance with the
provisions of the Exchange Offer. The Exchange Offer will expire at 5:00 P.M.,
New York City time, on        , 2002, unless the Exchange Offer is extended.
Any Old Notes tendered pursuant to the Exchange Offer may be withdrawn at any
time before the expiration of the Exchange Offer.

  Your attention is directed to the following:

    1. The Exchange Offer is for any and all Old Notes.

    2. The Exchange Offer is subject to certain conditions set forth in the
  Prospectus under the caption "The exchange offer--Conditions to the
  exchange offer."

    3. Any transfer taxes incident to the transfer of Old Notes from the
  holder to USON will be paid by USON, except as otherwise provided in
  Instruction 13 of the Letter of Transmittal.

    4. The Exchange Offer expires at 5:00 P.M., New York City time, on
          , 2002, unless the Exchange Offer is extended.

  If you wish to have us tender your Old Notes, please so instruct us by
completing, executing and returning to us the instruction form on the back of
this letter. The Letter of Transmittal is furnished to you for information
only and may not be used directly by you to tender Old Notes.
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                         INSTRUCTIONS WITH RESPECT TO
                              THE EXCHANGE OFFER

  The undersigned acknowledge(s) receipt of your letter and the enclosed
materials, referred to therein relating to the Exchange Offer made by US
Oncology, Inc. with respect to its Old Notes.

  This will instruct you to tender the Old Notes held by you for the account
of the undersigned, subject to the terms and conditions set forth in the
Prospectus and the related Letter of Transmittal.

  Please tender the Old Notes held by you for my account as indicated below:


  9 5/8% Senior Subordinated Notes due 2012 $        (Aggregate Principal
  Amount of Old Notes)


  [_] Please do not tender any Old Notes held by you for my account.

  Dated:          , 2002

Signature(s):__________________________________________________________________

Print Name(s) here:____________________________________________________________

(Print Address(es)):___________________________________________________________

(Area Code and Telephone Number(s)):___________________________________________

(Tax Identification or Social Security Number(s)):_____________________________


  None of the Old Notes held by us for your account will be tendered unless we
receive written instructions from you to do so. Unless a specific contrary
instruction is given in the space provided, your signature(s) hereon shall
constitute an instruction to us to tender all the Old Notes held by us for
your account.

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