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                      AGREEMENT BY AND BETWEEN SHAREHOLDERS
                                  OF, AND WITH,
                 U.S. CANCER CARE, INC., A DELAWARE CORPORATION


         THIS AGREEMENT (this "Agreement") is entered into effective as of May
22, 1998, by and among JOHN J. FUERY M.D., W. BRIAN FUERY, JEFFREY A. GOFFMAN,
STANLEY TROTMAN, ERNEST A. BATES, M.D., GORDON C. RAUSSER, RANDALL SKLAR,
CHARLES JACOBSON, RANDY SKLAR, STEPHEN PEZZOLA, DAVID GILO and RICHARD PADELFORD
(collectively the "Original Shareholders").

                                    RECITALS

         A. The Original Shareholders are the owners in the aggregate, of Three
Million Nine Hundred Thousand (3,900,000) shares of the issued and outstanding
common stock, one cent ($.01) par value per share (the "Common Stock") (or of
options to purchase Common Stock) of U.S. Cancer Care, Inc., a Delaware
corporation (the "Corporation").

         B. The Original Shareholders deem it to be in the best interests of the
Corporation and its Shareholders (as defined herein) to specify the membership
of the board of directors of the Corporation and to amend the certificate of
incorporation and the bylaws of the Corporation to require a super majority vote
of the Shareholders for certain corporate actions.

         C. The Original Shareholders desire to enter into an agreement to be
specifically enforceable against each of them pursuant to which they agree to
vote their shares of the Capital Stock (as defined herein) of the Corporation in
the manner and for the purposes specified herein.

         D. The Original Shareholders and the Corporation further consider it to
be in the best interests of the Shareholders and the Corporation to provide for
certain restrictions on the transfer of Capital Stock, and to create certain
options for the purchase and/or sale of Capital Stock, all as provided herein.

                                    AGREEMENT

                                   ARTICLE I
                          DEFINITIONS AND CONSTRUCTION

         1.1 DEFINITIONS. For purposes of this Agreement, unless the context
otherwise requires, the following terms have the respective meanings set out
below.

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         a. "AGREEMENT" shall have the meaning ascribed thereto in the preamble
of this Agreement.

         b. "CLOSING" shall mean the transfer of the Shares, or any portion
thereof, of a Transferor Shareholder to the Corporation and/or to some or all of
the Remaining Shareholders.

         c. "CAPITAL STOCK" shall mean any (i) shares of Common Stock or any
other equity security of the Corporation as may now or hereafter be authorized
for issuance by the Corporation, (ii) debt securities convertible into or
exchangeable for any security of the Corporation, (iii) any debt security or
capitalized lease with any entity feature with respect to the Corporation, and
(iv) options, warrants or other rights to subscribe for, purchase or otherwise
acquire any such security or debt security of the Corporation.

         d. "CLOSING DATE" shall mean the date on which the Closing is to occur
as provided in this Agreement.

         e. "COMMON STOCK" shall have the meaning ascribed thereto in the
preamble of this Agreement.

         f. "CORPORATION" shall have the meaning ascribed thereto in the
preamble of this Agreement.

         g. "DECEASED SHAREHOLDER" shall mean any Person who dies while a record
owner of any Shares.

         h. "DISABILITY" shall have the meaning ascribed thereto in Section
3.3.1

         i. "FUERY DESIGNEES" shall mean the Persons designated to the Board of
Directors of the Corporation by W. Brian Fuery and John J. Fuery, M.D. (or the
survivor of W. Brian Fuery and John J. Fuery, M.D.) from time to time pursuant
to the terms of this Agreement. The initial Fuery Designees shall be W. Brian
Fuery, John J. Fuery, M.D. and Stephen Pezzola.

         j. "GOFFMAN DESIGNEES" shall mean the Persons designated to the Board
of Directors of the Corporation by Jeffrey A. Goffman from time to time,
pursuant to the terms of this Agreement. The initial Goffman Designees shall be
Jeffrey A. Goffman, Stanley Trotman, Ernest A. Bates, M.D., Gordon C. Rausser,
Charles Jacobson and a ninth director as shall be designated by Jeffrey A.
Goffman.

         k. "OFFER" shall have the meaning ascribed thereto in Section 7.2.



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         l. "OFFERED SHARES" shall have the meaning ascribed thereto in Section
7.2.

         m. "ORIGINAL SHAREHOLDERS" shall have the meaning ascribed thereto in
the preamble of this Agreement.

         n. "PERSON" shall mean any individual, corporation, limited or general
partnership, limited liability company, joint venture, association, joint stock
company, trust, unincorporated organization, or any other entity, union or
association or government or any agency or political subdivision thereof.

         o. "PERSONAL REPRESENTATIVE" shall mean the executor, administrator or
other personal representative of the estate of a Deceased Shareholder.

         p. "PURCHASE PRICE" shall mean the price to be paid per Share subject
to this Agreement.

         q. "REMAINING SHAREHOLDERS" shall mean the Shareholders other than a
Transferor or a Deceased Shareholder.

         r. "SECURITIES" shall mean, with respect to any Person, such Person's
capital stock or any options, warrants or other securities which are directly or
indirectly convertible into, or exercisable or exchangeable for, such Person's
capital stock (whether or not such derivative Securities are issued by the
Corporation). Whenever a reference herein to Securities refers to any derivative
Securities, such reference shall apply to such derivative Securities and all
underlying Securities directly or indirectly issuable upon conversion, exchange
or exercise of such derivative Securities.

         s. "SHAREHOLDERS" shall mean the Original Shareholders and Subsequent
Shareholders, if any.

         t. "SHARES" shall mean the number of shares of the Corporation's voting
Capital Stock now owned or hereafter acquired by a Shareholder. The voting
Capital Stock of the Original Shareholders is set forth on Exhibit B annexed
hereto.



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         u. "SUBSEQUENT SHAREHOLDERS" shall mean such other Persons who may from
time to time execute a counterpart copy of this Agreement and whose names will
be set forth in an Exhibit C to be annexed hereto.

         v. "TRANSFER" shall mean and include any direct or indirect offer,
sale, pledge, assignment, hypothecation, encumbrance, the subjecting to a
security interest, or other conveyance of any Securities, any portion of any
Security, or any interest in any Security, whether voluntary or involuntary, and
including any transfer by way of operation of law.

         w. "TRANSFEROR SHAREHOLDER" shall mean any Shareholder Transferring, or
proposing to Transfer, his Shares.

         x. "WRITTEN CONSENT" shall mean that Written Consent of Shareholders
described in Article II, a copy of which is attached hereto as Exhibit A.

    1.2  CONSTRUCTION.

         a. CAPTIONS. The captions of Articles, Sections and Subsections of this
Agreement are inserted for convenience only and shall not affect the meaning or
construction of the contents of this Agreement.

         b. EXHIBITS. The exhibits to this Agreement are integral parts of this
Agreement and are hereby incorporated herein by this reference as if fully set
forth herein.

         c. MANDATORY AND PERMISSIBLE ACTS. As used in this Agreement, the words
"shall" and "will" refer to mandatory acts, and "may" shall refer to a
permissible act.

         d. REFERENCES. References in this Agreement to Articles, Sections, and
Subsections, unless specifically stated otherwise, are to the articles, sections
and subsections of this Agreement.

         e. MISCELLANEOUS TERMS. The term "or" shall not be exclusive. The terms
"herein," "hereof," "hereto," "hereunder" and other terms similar to such terms
shall refer to this Agreement as a whole and not merely to the specific article,
section, paragraph or clause where such terms may appear. The term "including"
shall mean "including, but not limited to".

                                   ARTICLE II
             SHAREHOLDER ACTION CONCERNING ELECTION OF DIRECTORS AND
            PROVISIONS TO BE INCLUDED IN CERTIFICATE OF INCORPORATION

    Each Original Shareholder agrees to execute simultaneously herewith the
Written Consent in the form attached hereto as Exhibit A. Each Original
Shareholder expressly agrees to



                                       4

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all action to be taken pursuant to the Written Consent, including the following:
(a) the election of the Persons specified in the Written Consent as directors of
the Corporation, (b) providing in the Corporation's certificate of incorporation
that the following actions may be taken only upon the unanimous affirmative vote
of the directors or the consent of no less than eighty per cent (80%) of the
outstanding Securities of the Corporation entitled to vote: (i) amendment of the
certificate of incorporation, (ii) amendment of the bylaws of the corporation,
(iii) issuance of common or preferred stock at less than fair market value, (iv)
self-dealing or related-party transactions, (v) any merger or consolidation of
the Corporation or any subsidiary of the Corporation, and (vi) any sale, lease,
exchange, mortgage, pledge, grant of a security interest in, transfer or other
disposition (in one transaction or a series of transactions), directly or
indirectly, of all or substantially all of the assets of the Corporation, (c)
providing that the Corporation may incur debt convertible to an equity interest
in the Corporation only by the consent of all of the directors less one (1) or
the consent of no less than eighty per cent (80%) of the outstanding Securities
of the Corporation entitled to vote; and (d) providing in the Corporation's
bylaws that the following actions may be taken only upon the unanimous
affirmative vote of the directors or the consent of no less than eighty per cent
(80%) of the outstanding Securities of the Corporation entitled to vote: (i)
payment to any consultant or employee of any sum (whether in one or a series of
payments) in excess of One Hundred Thousand Dollars ($100,000) unless
specifically so provided in a consulting agreement or employment contract, (ii)
the establishment of any stock plan or stock option plan (other than any such
plan or plans as are described in the private offering memorandum of the
Corporation dated February 13, 1998, as supplemented by supplements numbered 1,
2, and 3 dated March 30, 1998, April 24, 1998, and May 13, 1998 respectively,
and (iii) the issuance of any warrants, options or rights under an employee
stock option plan (other than as are described in said private offering
memorandum), it being understood that this provision shall not apply to the
issuance of any securities described in said private offering memorandum.

                                  ARTICLE III
                                VOTING AGREEMENT

         Each of the Shareholders hereby agrees to vote all of the shares in the
corporation now or hereafter registered in his name in favor of and in order to:

         3.1 INITIAL ELECTION. Elect as directors of the Corporation pursuant to
the Written Consent each of the following Persons: John J. Fuery, M.D., W. Brian
Fuery, Stephen Pezzola, Jeffrey A. Goffman, Stanley Trotman, Ernest A. Bates,
M.D., Gordon C. Rausser, Charles Jacobson and a ninth director as shall be
designated by Jeffrey A. Goffman.

         3.2 FUTURE ELECTIONS. Continue to vote for the Persons elected as
directors in accordance with this Agreement or any successor directors
designated in accordance with Section 3.3 as directors of the Corporation from
the date hereof until the termination of this Agreement; provided, however, that
John J. Fuery, M.D. and W. Brian Fuery may designate in



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writing a Person other than Stephen Pezzola to serve as a director, subject to
the consent of the other directors of the Corporation, which consent shall not
be unreasonably withheld.

         3.3 CHANGES IN MEMBERSHIP OF BOARD IF NO ADDITIONAL SHARES ISSUED.

                  3.3.1. Subject to the provisions of Section 3.4, in the event
that any Fuery Designee can not or will not serve as a director or ceases
serving as a director of the Corporation for any reason whatsoever, W. Brian
Fuery and John J. Fuery, M.D. (or in the event of his death or Disability, the
executor, administrator or personal representative of W. Brian Fuery or John J.
Fuery, M.D.) shall designate in writing within fifteen (15) days that such Fuery
Designee ceases serving as a director of the Corporation, in his or their sole
discretion, a successor director and the Shareholders agree to vote, or cause
their stock to be voted, for such Person or Persons as shall be designated
(subject to the consent of the other directors of the Corporation, which consent
shall not be unreasonably withheld). Disability as used herein shall mean that
for a period of ninety (90) consecutive days or six (6) months in any twelve
(12)-month period a Person is incapable of substantially fulfilling his
obligations hereunder because of physical, mental or emotional incapacity
resulting from injury, sickness or disease.

                  3.3.2. Subject to the provisions of Section 3.4, in the event
that any Goffman Designee can not or will not serve as a director or ceases
serving as a director of the Corporation for any reason whatsoever, Jeffrey A.
Goffman (or in the event of his death or Disability, the executor, administrator
or personal representative of Mr. Goffman shall designate, in his sole
discretion, a successor director and the Shareholders agree to vote, or cause
their stock to be voted, for such Person or Persons as shall be designated.

         3.4 ANTIDILUTION PROVISIONS. In the event that additional shares of
Capital Stock are issued to John J. Fuery, M.D. and W. Brian Fuery pursuant to
the provisions of section 5.4 of that Plan and Agreement of Merger of United
States Cancer Care, a California corporation, into USCC Acquisition Corporation,
a Delaware corporation, dated May 22, 1998, then the number of directors of
U.S.C.C. Delaware, which John J. Fuery, M.D. and W. Brian Fuery are entitled to
elect shall be the greater of (a) three or (b) that proportion (rounded up or
down to the nearest whole number) of the total number of directors which the
shares in U.S.C.C. Delaware, entitled to vote for directors held by John J.
Fuery, M.D. and W. Brian Fuery bears to the total number of issued and
outstanding shares in U.S.C.C. Delaware, entitled to vote for directors. In the
event that John J. Fuery, M.D. and W. Brian Fuery should be entitled to elect
one (1) or more additional directors as a result of the operation of this
antidilution provision, then the Shareholders agree to vote, or cause their
stock to be voted, for such Person or Persons as shall be designated in writing
by John J. Fuery, M.D. and W. Brian Fuery (or in the event of the death or
Disability of John J. Fuery, M.D. or W. Brian Fuery, by his executor,
administrator or



                                       6

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personal representative) for such additional directorship or directorships,
subject to the consent of the other directors of the Corporation, which consent
shall not be unreasonably withheld.

                                   ARTICLE IV
                            CHANGES IN CAPITAL STOCK

                  In the event that subsequent to the date of this Agreement any
Capital Stock or other Securities (other than Securities of another corporation
issued to the Corporation's Shareholders pursuant to a plan of merger) are
issued on, or in exchange for, any of the shares of Capital Stock in the
Corporation now held by the Original Shareholders by reason of any stock
dividend, stock split, consolidation of shares, reclassification, or
consolidation involving the Corporation, including any additional shares issued
to John J. Fuery, M.D. and W. Brian Fuery as provided in Section 3.4, such
Capital Stock or Securities shall be deemed to be Capital Stock subject to this
Agreement for purposes of this Agreement.

                                   ARTICLE V
                         REPRESENTATIONS OF SHAREHOLDERS

                  Each Shareholder hereby represents and warrants to each of the
other Shareholders that (a) he owns and has the right to vote the number of
shares of the Capital Stock of the Corporation set forth opposite his name on
Exhibit B attached hereto, (b) he has full power to enter into this Agreement
and has not, prior to the date of this Agreement, executed or delivered any
proxy or entered into any other voting agreement or similar arrangement other
than one which has expired or terminated prior to the date hereof, and (c) he
will not take any action inconsistent with the purposes and provisions of this
Agreement.

                                   ARTICLE VI
                        RESTRICTION ON TRANSFER OF SHARES

                  No Shares shall be Transferred except as provided in this
Agreement. Any attempted Transfer of Shares in violation of this Agreement shall
be void and of no effect and shall not operate to transfer any interest or title
to the purported transferee.

                                  ARTICLE VII
                            TRANSFERS DURING LIFETIME

7.1 PROPOSED SALE SUBJECT TO THIS AGREEMENT. Until such time as the Corporation
is deemed to be a public company for purposes of the Securities Exchange Act of
1934, if a Shareholder desires to Transfer any of his Shares pursuant to a bona
fide third-party offer to purchase such Shares, the Transferor Shareholder may
not sell such Shares except pursuant to the provisions of this Article VII and
subject to all terms and conditions of this



                                       7

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Agreement. From and after the time that the Corporation is deemed to be a public
company for purposes of the Securities Exchange Act of 1934, the provisions of
this Article VII and Article VIII shall be inapplicable.

         7.2 NOTICE AND FIRST OFFER TO CORPORATION. The Transferor Shareholder
shall deliver written notice to the Corporation of the Transferor Shareholder's
intention to Transfer all or a portion of his Shares (the "Offered Shares")
pursuant to a bona fide third-party offer by first offering to sell such Offered
Shares to the Corporation at the price and on the terms of said third-party
offer (the "Offer"). The Offer shall include reasonable proof of the existence
of the bona fide third-party offer to purchase the Shares, including a copy of
such offer from the proposed third-party transferee, the identity of the
proposed third-party transferee, the number of Offered Shares proposed to be
sold, the total number of Shares owned by the Transferor Shareholder, the terms
and conditions of the proposed sale, including a description and a statement of
the aggregate cash value of all consideration, including any consideration other
than cash, the address of the Transferor Shareholder and any other material
facts relating to the proposed sale. For a period of thirty (30) days following
the date the Offer is delivered by the Transferor Shareholder to the
Corporation, the Corporation shall have the right to purchase any portion of the
Shares offered. The Corporation shall exercise this right by delivering written
notice of its election to purchase such offered Shares to the Transferor
Shareholder. In the event that the consideration to be paid for the Offered
Shares by the Corporation shall include any consideration other than cash, and
the Offer includes a fair market value of such non-cash consideration in
accordance with this Section 7.2 which the Corporation objects to, the
Corporation shall set forth such objection in such notice. If the Transferor
Shareholder and the Corporation cannot agree on a valuation within five (5)
business days following the delivery of such notice, then the dispute shall be
referred to a nationally recognized investment banking firm selected jointly by
the Transferor Shareholder and the Corporation. If the Transferor Shareholder
and the Corporation cannot agree on the selection of an investment banking firm,
then the Transferor Shareholder and the Corporation shall each select one (1)
such firm and such firms shall designate a mutually acceptable investment
banking firm with a nation-wide reputation to determine the aggregate value of
all consideration proposed to be paid by the Corporation for the Offered Shares.
The expenses of such investment banking firm shall be paid by the Corporation.
All determinations made pursuant to this Section 7.2 shall be final, conclusive
and binding on the Transferor Shareholder and the Corporation.

         7.3 NOTICE AND SECOND OFFER TO REMAINING SHAREHOLDERS. If the
Corporation does not elect to purchase all of the Offered Shares which the
Transferor Shareholder proposes to Transfer, the Transferor Shareholder shall,
within five (5) days after the expiration of the Corporation's right to do so,
deliver the Offer together with notice of the number of Offered Shares, if any,
which the Corporation has elected to Purchase to the Remaining Shareholders who
shall, for a period of thirty (30) days after the delivery to them of the Offer,
have the right to purchase the Offered Shares specified in the Offer which have
not been purchased by the Corporation by delivering written notice of such
election to the Transferor Shareholder, specifying the number of Offered Shares
each Remaining Shareholder elects to purchase. In the event that the
consideration proposed to be paid for the Offered Shares by the



                                       8

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Remaining Shareholders shall include any consideration other than cash, and the
Offer includes a fair market value of such non-cash consideration in accordance
with Section 7.2 hereof which the Remaining Shareholders object to, the
Remaining Shareholders shall set forth such objection in such notice. If a
majority of the Remaining Shareholders and the Corporation cannot agree on a
valuation within five (5) business days following the delivery of such notice,
then the dispute shall be referred to a nationally recognized investment banking
firm selected jointly by a majority of the Remaining Shareholders and the
Corporation. If a majority of the Remaining Shareholders and the Corporation
cannot agree on the selection of an investment banking firm, then a majority of
the Remaining Shareholders and the Corporation shall each select one (1) such
firm and such firms shall designate a mutually acceptable investment banking
firm with a nation-wide reputation to determine the aggregate value of all
consideration proposed to be paid by the Remaining Shareholders for the Offered
Shares. The expenses of such investment banking firm shall be paid by the
Corporation. All determinations made pursuant to this Section 7.3 shall be
final, conclusive and binding on the Remaining Shareholders and the Corporation.
If the total number of the Offered Shares which the Remaining Shareholders elect
to purchase exceeds the number subject to the Offer remaining unpurchased by the
Corporation, then, within five (5) days following the expiration of the thirty
(30)-day period specified in the preceding sentence, the Transferor Shareholder
shall so notify each Remaining Shareholder desiring to purchase the Offered
Shares and each such Remaining Shareholder shall be entitled to purchase such
proportion of the Offered Shares remaining unpurchased by the Corporation as the
number of Shares which he holds bears to the total number of Shares held by all
such Remaining Shareholders desiring to purchase the Offered Shares which remain
unpurchased by the Corporation.

         7.4 OFFERED SHARES RELEASED FROM RESTRICTION. If all of the Offered
Shares subject to the Offer are not purchased by the Corporation and/or the
Remaining Shareholders within the applicable time periods specified in this
Article VII, then for a period of sixty (60) days after the expiration of such
time periods, the Transferor Shareholder may sell any remaining Offered Shares
to the bona-fide third-party offeree, for the price and on the terms specified
in the Offer; provided, however, that such intended transferee shall, prior to
the Transfer of such Offered Shares, agree in writing that the transferee shall
receive and hold such Offered Shares subject to all the provisions and
restrictions of this Agreement. Any proposed modification of the number of
Offered Shares or any agreement to Transfer Offered Shares after the expiration
of such sixty (60)-day period shall again require compliance with all of the
provisions of this Article VII.

                                  ARTICLE VIII
                             DEATH OF A SHAREHOLDER

         8.1 CORPORATION RIGHT TO PURCHASE. Upon the death of a Shareholder, the
Corporation shall have the right during the thirty (30)-day period commencing
with the date upon which the Corporation receives notice of such death to
purchase all or any portion of the



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Shares of the Deceased Shareholder for the price and on the terms set forth in
Sections 8.3, 8.4 and 8.5. As soon as possible following the death of a
Shareholder, the Personal Representative shall deliver written notice to the
Corporation of the Deceased Shareholder's death. The Corporation shall exercise
its right to acquire the Shares of a Deceased Shareholder by delivering written
notice of its election to purchase such Shares to the Personal Representative
within thirty (30) days following receipt by the Corporation of notice of death
from the Personal Representative. The Corporation shall specify the number of
the Deceased Shareholder's Shares it intends to purchase.

         8.2 REMAINING SHAREHOLDERS' RIGHTS TO PURCHASE. If the Corporation does
not elect to purchase all of the Deceased Shareholder's Shares, the Personal
Representative shall, within five (5) days after the expiration of the
Corporation's right to do so, deliver to the Remaining Shareholders notice of
the Deceased Shareholder's death which notice shall specify the number of
Shares, if any, which the Corporation has elected to purchase. The Remaining
Shareholders shall, for a period of thirty (30) days after the delivery to them
of said notice, have the right to purchase such of the Deceased Shareholder's
Shares as have not been purchased by the Corporation for the price and on the
terms specified in Sections 8.3, 8.4 and 8.5. If the total number of the Shares
which the Remaining Shareholders elect to purchase exceeds the number which the
Corporation has not purchased, then, within five (5) days following the
expiration of the thirty (30)-day period specified in the preceding sentence,
the Personal Representative shall so notify each Remaining Shareholder desiring
to purchase the Shares and each such Remaining Shareholder shall be entitled to
purchase such proportion of the Shares available to be purchased as the number
of Shares which he holds bears to the total number of Shares held by all such
Remaining Shareholders desiring to purchase the Shares referred to in the
notice.

         8.3 PURCHASE PRICE. The Purchase Price for the Shares of a Deceased
Shareholder shall be their fair market value as of the date of death as agreed
upon by the Corporation and the Personal Representative, if the Corporation
purchases all of the Deceased Shareholder's Shares, or by the Corporation, the
Remaining Shareholders purchasing Shares of the Deceased Shareholder and the
Personal Representative, if the Corporation and some or all of the Remaining
Shareholders purchase the Deceased Shareholder's Shares. If the parties are
unable to agree upon the fair market value, then the determination of fair
market value shall be submitted to arbitration in accordance with the provisions
of Article XIV.

         8.4 PAYMENT OF PURCHASE PRICE. At the election of the Corporation and
(if applicable) the Remaining Shareholders, the Purchase Price may be paid in
full in cash within ninety (90) days following the date of notice of the
Corporation's intent to purchase all of the Shares of the Deceased Shareholder
as required to be given in Section 8.1 or, if the Corporation does not purchase
all of the Shares of the Deceased Shareholder, within ninety (90) days following
the date of the notice of the Remaining Shareholder's intent to purchase Shares
of the



                                       10

<PAGE>

Deceased Shareholder as required to be given in Section 8.2, or by delivery of a
promissory note. The Purchase Price, as determined and paid in accordance with
the terms hereof, shall be payable to the Personal Representative only upon the
Personal Representative's (a) delivery of a stock certificate or certificates
for the Shares purchased, duly endorsed for transfer in blank, free and clear of
all liens and encumbrances, and (b) payment of all costs and expenses of the
Corporation and/or the Remaining Purchasers (as applicable) purchasing a
Deceased Shareholder's Shares incurred in connection with the transaction.

         8.5 SECURITY FOR DEFERRED PAYMENT OF PURCHASE PRICE. If any of the
Shares of the Deceased Transferor are purchased by delivery of a promissory note
as permitted by Section 8.4, the Personal Representative shall at the Closing
deposit in escrow the Shares so purchased, together with stock powers duly
endorsed for transfer in blank with an escrow agent chosen by mutual agreement
of the Personal Representative and the Corporation and/or the Remaining
Shareholders purchasing Shares of the Deceased Shareholder, as appropriate. The
Shares will be held in escrow to secure payment of the promissory note. If the
Personal Representative and the Corporation and/or the Remaining Shareholders
(as applicable) do not agree upon an escrow agent, then the escrow agent shall
be the bank then used by the Corporation for its checking account. The Shares
shall be deposited in escrow subject to escrow terms substantially as set forth
on Exhibit C attached hereto.

         8.6 SHARES NOT ACQUIRED BY CORPORATION OR REMAINING SHAREHOLDERS. If
all of the Deceased Shareholder's Shares are not purchased by the Corporation
and/or the Remaining Shareholders within the applicable time periods specified
in this Article VIII, then such Shares as are not acquired may be transferred to
such Person or Persons as are specified by the testamentary disposition of the
Deceased Shareholder or, if the Deceased Shareholder shall have died intestate,
to such Person or Persons as are, under the laws of intestate succession
governing the estate of the Deceased Shareholder, entitled to succeed to the
Deceased Shareholder's property in such Shares; provided, that any such
transferee shall, prior to the transfer of such Shares, execute a counterpart
copy of this Agreement, pursuant to which such transferee shall agree to receive
and hold such Shares subject to all the provisions and restrictions of this
Agreement.

                                   ARTICLE IX
                              CORPORATE LIMITATION

         Notwithstanding anything to the contrary herein, the Corporation shall
be prohibited from exercising its purchase options under this Agreement to the
extent such exercise would violate Section 163 of the Delaware General
Corporation Law.

                                   ARTICLE X
                        FAILURE OF TRANSFEROR TO PERFORM

         If a Transferor Shareholder or Personal Representative shall fail to
deliver the stock certificate or certificates representing the Shares purchased
by the Corporation and/or the Remaining Shareholders or some of them, duly
endorsed for transfer in blank, then the Purchase



                                       11

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Price for the Shares purchased by the Corporation and/or the Remaining
Shareholders may be tendered and delivered by the Corporation and/or the
Remaining Shareholders, as the case may be, to the Corporation for the account
and benefit of the Transferor Shareholder or the Personal Representative, as the
case may be, and the Transferor Shareholder or the Personal Representative, as
the case may be, shall be notified in writing of such action by the Corporation
on behalf of the Corporation and/or the Remaining Shareholders, as the case may
be. Said tender and delivery shall constitute valid payment for the Shares, and
the purchase of the Shares shall be deemed thereby to have been fully effected,
so that all right, title and interest in and to the purchased Shares shall be
vested, in the Corporation and/or the Remaining Shareholders, as the case may
be, and all rights of the Transferor Shareholder or the Personal Representative,
as the case may be, and any transferee, assignee or any other Person having any
interest through the Transferor Shareholder or the Personal Representative in
the Shares purchased by the Corporation and/or the Remaining Shareholders, as
the case may be, shall terminate except only for the right to receive the
Purchase Price for the purchased Shares and the right to have the purchased
Shares deposited into escrow when required by Section 7.5 to secure payment of
the Purchase Price therefor. The Secretary or Assistant Secretary of the
Corporation, as attorney-in-fact for and in the name of the Transferor
Shareholder or Personal Representative, as the case may be, shall cause the
purchased Shares to be transferred on the books of the Corporation to the
Corporation and/or the Remaining Shareholders, as the case may be.

         Each Shareholder does hereby irrevocably appoint and designate each of
the Secretary and the Assistant Secretary, if any, of the Corporation, and their
respective successors in office, as his attorneys-in-fact for and on his behalf,
and on behalf of his estate and his Personal Representative, to effect the
transfer of the purchased Shares on the books of the Corporation in the manner
provided above.

                                   ARTICLE XI
                                  STOCK LEGEND

                  All Shares subject to this Agreement shall have endorsed
thereon the following legend:

     "THE SALE, TRANSFER, ENCUMBRANCE OR OTHER DISPOSITION OF THE SHARES OF
     STOCK REPRESENTED BY THIS CERTIFICATE IS RESTRICTED BY AND SUBJECT TO THE
     PROVISIONS OF A STOCKHOLDERS BUY/SELL AGREEMENT BETWEEN U. S. CANCER CARE,
     INC. AND VARIOUS STOCKHOLDERS DATED MAY 22, 1998, A COPY OF WHICH MAY BE
     INSPECTED AT THE OFFICES OF THE CORPORATION. ANY PURPORTED SALE, TRANSFER,
     ENCUMBRANCE OR OTHER DISPOSITION IN VIOLATION OF SUCH AGREEMENT SHALL BE
     VOID."



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<PAGE>

                                  ARTICLE XII
                                TERM OF AGREEMENT

         Except as set forth in Article VII hereof, this Agreement shall
commence on the date first above written and shall terminate on the earlier to
occur of (a) the issuance by the Corporation of its shares in a public offering
that is salable without restrictions under the Securities Act of 1933, as
amended, or any rules promulgated thereunder, pursuant to which offering the
Shareholders receive publicly-traded stock, and subsequent to such offering the
Corporation's market capitalization is at least Fifty Million Dollars
($50,000,000), (b) the merger of the Corporation into another corporation,
pursuant to which merger the Shareholders receive publicly-traded stock, and the
surviving corporation of which merger has a value of not less than Fifty Million
Dollars ($50,000,000), (c) the sale of all or substantially all of the assets of
the Corporation for a purchase price of not less than One Hundred Million
Dollars ($100,000,000) (inclusive of the fair market value of any non-cash
consideration), or (d) such time as all of those Persons holding securities of
the Corporation (of whatever nature including, but not limited to, the Common
Stock, any notes or debentures convertible to stock of any class of the
Corporation, and warrants or options for the acquisition of stock of any class
of the Corporation) immediately following the Closing (as defined defined in the
Plan and Agreement of Merger of United States Cancer Care, Inc., a California
corporation, into USCC Acquisition Corp., a Delaware corporation) of the merger
of United States Cancer Care, Inc., into and with USCC Acquisition Corp., hold,
collectively, less than forty percent (40%) of all the Corporation's securities
of whatever nature.

                                  ARTICLE XIII
                            ENFORCEABILITY; VALIDITY

         Each Shareholder expressly agrees that this Agreement shall be
specifically enforceable in any court of competent jurisdiction in accordance
with its terms against each of the parties hereto, provided, however, that this
Agreement shall be null and void from and after the termination dates specified
in Article XII.

                                  ARTICLE XIV
                                   ARBITRATION

         Any dispute between the parties arising out of this Agreement (other
than an action for injunctive relief) shall be submitted to final and binding
arbitration in the State of Delaware, under the Commercial Arbitration Rules of
the American Arbitration Association then in effect, upon written notification
and demand of either party therefor. In making the award, the arbitrator shall
award recovery of costs and expenses of the arbitration and reasonable
attorneys' fees to the prevailing party. Should judicial proceedings or
arbitration be commenced to enforce



                                       13

<PAGE>

or carry out this provision or any arbitration award, the prevailing party in
such proceedings shall be entitled to reasonable attorneys' fees and costs in
addition to other relief.

                                   ARTICLE XV
                                   ENFORCEMENT

         In addition to any other remedies, the breach of any of the terms
hereof shall entitle the Corporation to injunctive relief. If the Corporation
shall bring an action against the undersigned for injunctive relief hereunder,
the prevailing party in any subsequent arbitration in connection therewith shall
be entitled to its costs of suit and attorneys' fees.

                                  ARTICLE XVI
                                  MISCELLANEOUS

         16.1 ASSIGNS. All the covenants and agreements contained in this
Agreement shall be binding upon, and shall enure to the benefit of, the
respective parties and their successors, assigns, heirs, executors,
administrators and other legal representatives, as the case may be.

         16.2 GOVERNING LAW. This Agreement, and the rights and obligations of
the parties hereto, shall be governed by and construed in accordance with the
internal laws of the State of Delaware, without regard to its conflict of laws
rules.

         16.3 COUNTERPART EXECUTION. This Agreement may be executed in one or
more counterparts, each of which shall be deemed an original but all of which
together shall constitute one and the same instrument.

         16.4 SEVERABILITY. If any provision or this Agreement shall be declared
void or unenforceable by any court or administrative board of competent
jurisdiction, such provision shall be deemed to have been severed from the
remainder of this Agreement and this Agreement shall continue in all respects to
be valid and enforceable.

         16.5 WAIVERS. No waivers of any breach of this Agreement extended by
any party hereto to any other party shall be construed as a waiver of any rights
or remedies of any other party hereto or with respect to any subsequent breach.



                                       14

<PAGE>



         IN WITNESS WHEREOF, the Shareholders have executed this Agreement as of
the date first above written.


/s/ John J. Fuery, M.D.                        /s/ W. Brian Fuery
-------------------------------------          ---------------------------------
John J. Fuery, M.D.                            W. Brian Fuery


/s/ Jeffrey A. Goffman                         /s/ Stanley Trotman
-------------------------------------          ---------------------------------
Jeffrey A. Goffman                             Stanley Trotman


/s/ Gordon C. Rausser                          /s/ Ernest A. Bates, M.D.
-------------------------------------          ---------------------------------
Gordon C. Rausser                              Ernest A. Bates, M.D.


/s/ Randy C. Sklar                             /s/ Charles Jacobson
-------------------------------------          ---------------------------------
Randy C. Sklar                                 Charles Jacobson


/s/ Richard Padelford                          /s/ Stephen Pezzola
-------------------------------------          ---------------------------------
Richard Padelford                              Stephen Pezzola


/s/ Davidi Gilo
-------------------------------------
Davidi Gilo




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