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                         ASSIGNMENT OF AND AMENDMENT TO
                       THE PROFESSIONAL SERVICES AGREEMENT
                         FOR RADIATION THERAPY SERVICES
                                     BETWEEN
                     USCC HEALTHCARE MANAGEMENT CORPORATION,
                     RADIATION ONCOLOGY MEDICAL GROUP, INC.
                                       AND
                       THE PERMANENTE MEDICAL GROUP, INC.

THIS ASSIGNMENT OF AND AMENDMENT TO AGREEMENT ("Assignment and Amendment") is
made and entered into as of August 1, 2000, by and between The Permanente
Medical Group, Inc., a California professional medical corporation ("TPMG"),
Radiation Oncology Medical Group ("ROMG"), a California professional medical
corporation, USCC Health Care Management Corporation, a California corporation
("USCC"), USCC Medical Group-CA, Inc., a California professional corporation
("USCCMGCA"), and The USCMC-USCC Partnership, a partnership between US Cancer
Management Corporation and USCC ("PARTNERSHIP").

                                   WITNESSETH:

A. Contractor and TPMG have heretofore entered into an agreement effective
August 1, 1999, for Contractor to provide Radiation Therapy Services for Members
(the "Agreement").

B. The parties hereto desire to amend the Agreement in the manner hereinafter
set forth.

NOW THEREFORE, the parties agree as follows:

A. Effective August 1, 2000, the Agreement is amended as set forth below.

B. All other terms and conditions of the Agreement are to remain the same.

                I. ASSIGNMENT AND AMENDMENT #1 - STOCKTON CENTER

A.       RECITALS ARE AMENDED AS FOLLOWS:

         1. SECTION H is added as follows: "H. It is the parties' understanding
         that Contractor has developed a new medical group, Johnson and
         Tepperman Medical Group, Inc., d.b.a. USCC Medical Group - CA, Inc.
         ("USCCMGCA"), for Services provided at the Stockton Center (St. Teresa
         Comprehensive Cancer Center). At this time, ROMG ("Assignor-1") desires
         to assign its interest and obligations under this Assignment and
         Amendment, as related to the Stockton (St. Teresa) Center, to USCCMGCA
         ("Assignee-1")."

B.       TERMS OF THE AGREEMENT ARE AMENDED AS FOLLOWS:

NOW, THEREFORE, in consideration of the mutual promises set forth herein and for
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties agree as follows:

         1. ASSIGNMENT. Assignor-1 hereby assigns and transfers all right, title
         and interest in and to the Agreement, for the Stockton Center, to
         Assignee-1, effective as of February 22, 2000.


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         2. ACCEPTANCE OF ASSIGNMENT. Assignee-1 hereby accepts assignment and
         transfer of all right, title and interest in and to the Agreement, and
         expressly assumes and agrees to perform and be bound by all terms,
         conditions and obligations of Assignor-1 under the Agreement for
         Services provided at the Stockton Center.

         3. ASSIGNEE-1 REPRESENTATIONS AND WARRANTIES. Assignee-1 represents and
         warrants that Assignee-1 (a) has the authority to execute this
         Assignment and Amendment, and (b) has assumed all obligations and
         liabilities of Assignor-1 relating to the Stockton Center arising under
         or related to the Agreement arising on or after February 22, 2000.

         4. ASSIGNOR-1 REPRESENTATIONS AND WARRANTIES. Assignor-1 represents and
         warrants that no services were provided under the Agreement as part of
         the Stockton Center before February 22, 2000 and, thus, no tail
         insurance for prior periods is required.

         5. TPMG CONSENT. TPMG hereby consents to the assignment and assumption
         described in this Assignment and Amendment.

         6. NOTICES. The parties hereby agree that all notices regarding the
         Stockton Center required under the Agreement to be directed to
         Assignor-1 shall henceforth be directed to Assignee-1 at the following
         address:

                           USCC Medical Group - CA, Inc.
                           c/o US Cancer Care
                           700 Ygnacio Valley Rd., #300
                           Walnut Creek, CA  94596

         7. PAYMENT BY KP. The parties acknowledge and agree that all payments
         due and owing from KP to Assignor-1 pursuant to the Agreement for the
         Stockton Center shall hereinafter be made to Assignee-1, provided,
         however, that KP's payment (a) to Assignor-1 of amounts owing to
         Assignee-1, or (b) to Assignee-1 of amounts owing to Assignor-1, shall
         be resolved between Assignor-1 and Assignee-1 without liability on the
         part of KP.

         8. BINDING ON SUCCESSORS. The terms of this Assignment and Amendment
         shall be binding on the parties' successors and assigns.

         9. COUNTERPARTS. This Assignment and Amendment may be executed in two
         or more counterparts, each constituting an original and all taken
         together constituting one and the same document.

         10. DESIGNATION. The parties agree that each reference in the Agreement
         to ROMG shall now also refer to USCCMGCA. The term "Contractor" shall
         jointly and separately refer to USCC, ROMG and USCCMGCA.

            II. ASSIGNMENT AND AMENDMENT #2 - SAN RAFAEL, SANTA ROSA,
                               AND FUTURE CENTERS

A.       RECITALS ARE AMENDED AS FOLLOWS:

         1. SECTION I is added as follows: "I. USCCMGCA is a California
         professional medical corporation that provides certain outpatient
         radiation oncology services in facilities and with equipment owned or
         leased by USCC. USCCMGCA's T1N number is: 77-0536884."

         2. SECTION J is added as follows: "J. It is the parties' understanding
         that USCC has developed a new partnership ("PARTNERSHIP") with US
         Cancer Management Corporation. ("USCMC") for the future development of
         Services for TPMG, including the currently planned San Rafael and Santa
         Rosa Centers. A copy of the PARTNERSHIP's agreement is attached as
         Addendum A. At this time, USCC ("Assignor-2") desires to assign its
         interest and obligations

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         under the Agreement, as related to the San Rafael and Santa Rosa
         Centers, and such future Centers that the parties desire to develop, to
         PARTNERSHIP ("Assignee-2").

         3. SECTION K is added as follows: "K. USCMC is a Delaware corporation.
         USCMC's T1N number is: 68-0451110. PARTNERSHIP owns and leases
         outpatient radiation oncology facilities and equipment and, provides
         certain administrative services to ROMG USCCMG-CA and TPMG.
         PARTNERSHIP's T1N has been applied for and will be provided to TPMG
         after receipt."

B.       TERMS OF THE AGREEMENT ARE AMENDED AS FOLLOWS:

NOW, THEREFORE, in consideration of the mutual promises set forth herein and for
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties further agree as follows:

         1. ASSIGNMENT. Assignor-2 hereby assigns and transfers all right, title
         and interest in and to the Agreement, for the Santa Rosa and San Rafael
         Centers and such future Centers that the parties develop, to
         Assignee-2, effective as of August 1, 2000.

         2. ACCEPTANCE OF ASSIGNMENT. Assignee-2 hereby accepts assignment and
         transfer of all right, title and interest in and to the Agreement, and
         expressly assumes and agrees to perform and be bound by all terms,
         conditions and obligations of Assignor-2 under the Agreement for
         Services provided at the Santa Rosa and San Rafael Centers and such
         future Centers that the parties develop.

         3. ASSIGNEE-2 REPRESENTATIONS AND WARRANTIES. Assignee-2 represents and
         warrants that Assignee-2 (a) has the authority to execute this
         Assignment and Amendment, and (b) has assumed all obligations and
         liabilities of Assignor-2 arising for the Santa Rosa and San Rafael
         Centers and such future Centers that the parties develop under or
         related to the Agreement arising on or after February 22, 2000.

         4. ASSIGNOR-2 REPRESENTATIONS AND WARRANTIES. Assignor-2 represents and
         warrants that no services were provided under the Agreement as part of
         the Santa Rosa and San Rafael Centers before August 1, 2000, and, thus,
         no tail insurance for prior periods is required.

         5. TPMG CONSENT. TPMG hereby consents to the assignment and assumption
         described in this Assignment and Amendment.

         6. NOTICES. The parties hereby agree that all notices regarding the San
         Rafael, Santa Rosa or future sites required under the Agreement to be
         directed to Assignor-2 shall henceforth be directed to Assignee-2 at
         the following address:

                           USCC - USCMC PARTNERSHIP
                           700 Ygnacio Valley Rd., #300
                           Walnut Creek CA  94596

         7. PAYMENT BY KP. The parties acknowledge and agree that all payments
         due and owing from KP to Assignor-2 pursuant to the Agreement for the
         Santa Rosa and San Rafael Centers and such future Centers that the
         parties develop shall hereinafter be made to Assignee-2, provided,
         however, that KP's payment (a) to Assignor-2 of amounts owing to
         Assignee-2, or (b) to Assignee-2 of amounts owing to Assignor-2, shall
         be resolved between Assignor-2 and Assignee-2 without liability on the
         part of KP.

         8. BINDING ON SUCCESSORS. The terms of this Assignment and Amendment
         shall be binding on the parties' successors and assigns.

         9. COUNTERPARTS. This Assignment and Amendment may be executed in two
         or more counterparts, each constituting an original and all taken
         together constituting one and the same document.


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         10. DESIGNATION. The parties agree that, hereinafter, all references to
         USCC shall also refer to PARTNERSHIP as it pertains to obligations and
         privileges of the parties for their respective centers. The term
         "Contractor" shall jointly and separately refer to USCC, PARTNERSHIP,
         USCMC, ROMG and USCCMGCA.

                           III. ADDITIONAL AMENDMENTS

NOW, THEREFORE, in consideration of the mutual promises set forth herein and for
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties lastly agree as follows:

A.       SECTION 2.7.  THE FOLLOWING IS HEREBY ADDED AT THE END OF SECTION 2.7:

         "The requirements of this Section apply individually and collectively
         to USCC, USCMC, ROMG, USCCMGCA and PARTNERSHIP. Further, PARTNERSHIP
         agrees to provide advance notice to TPMG of any intended material
         changes in the its partnership agreement including but not limited to
         the roles and responsibilities of the partners and financial status of
         the partnership. PARTNERSHIP also agrees to provide upon request by
         TPMG copies of financial statements of the partnership and copies of
         the current partnership agreement."

B.       CONFIDENTIAL TERMS HAVE BEEN OMITTED AND FILED SEPARATELY WITH THE
         SECURITIES AND EXCHANGE COMMISSION

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C.       SECTION 3.4(b)(v) IS HEREBY DELETED AND REPLACED BY THE FOLLOWING,
         EFFECTIVE AUGUST 1, 1999:

         (v) Regular Medicare. If Contractor provides Services to a Regular
         Medicare Member, then Contractor shall submit the bill directly to
         HCFA. Upon receipt of a copy of the Explanation of Medicare Benefits
         and an invoice, TPMG shall pay Contractor any applicable Medicare
         coinsurance and deductible amounts, and any amounts due for Services
         that are Covered Benefits but are not covered by Medicare. Contractor
         shall not assert any claim for compensation against Regular Medicare
         Members for Medicare-covered Services, and shall not assert any claim
         for compensation, other than for the applicable Medicare coinsurance
         and deductible amounts, against TPMG for Medicare-covered Services
         provided to such Members. Contractor agrees to accept, as payment in
         full for Services provided to Regular Medicare Members, (a) the
         applicable Medicare payment, (b) the amounts paid by TPMG for the
         applicable Medicare coinsurance and deductible, and (c) the amount paid
         by TPMG, if any, for Services that are Covered Benefits but are not
         Covered by Medicare.

D.       EXHIBIT 3; EXHIBIT 3A (HAYWARD) AND EXHIBIT 3B (STOCKTON) ARE HEREBY
         DELETED AND REPLACED BY THE ATTACHED EXHIBIT 3A (HAYWARD) AND EXHIBIT
         3B (STOCKTON) EXHIBIT 3C (SAN RAFAEL) AND EXHIBIT 3D SANTA ROSA):

E.       SECTION 4.1 IS HEREBY DELETED AND REPLACED WITH THE FOLLOWING:

         "4.1 TERM. This Agreement will begin on the Effective Date (specific to
         each Center), and will continue in effect for three (3) years for the
         Hayward and Stockton Centers and five (5) years for the San Rafael and
         Santa Rosa Centers, and such future Centers that the parties develop.
         This Agreement will thereafter automatically renew for each Center for
         successive five (5) year terms based upon each Center's initial
         effective date, unless terminated in accord with Sections 4.2, 4.3, or
         4.4, below. Further, if either party desires to allow the Agreement to
         expire at the end of the initial or any subsequent term, the party
         shall give written notice of such intent to the other party at least
         One Hundred Eighty (180) days prior to the end of that term."

F.       SECTION 9.5 IS HEREBY DELETED AND REPLACED WITH THE FOLLOWING:

         "9.5 ASSIGNMENT. Subject to the provisions related to successors set
         forth below, neither this Agreement nor any duties or obligations under
         this Agreement may be assigned or subcontracted by USCC, USCMC,
         PARTNERSHIP, ROMG and/or USCCMGCA without the prior written consent of
         TPMG. TPMG agrees that such consent shall not be unreasonably withheld.
         CONFIDENTIAL TERMS HAVE BEEN OMITTED AND FILED SEPARATELY WITH THE
         SECURITIES AND EXCHANGE COMMISSION. Any material change of ownership or
         control of USCC, USCMC, PARTNERSHIP, ROMG and/or USCCMGCA shall be
         deemed an assignment of this Agreement requiring the prior written
         consent of TPMG. If DHS or a Medi-Cal Plan's approval is required by
         law or Health Plan Medi-Cal Contracts, assignment or delegation of this
         Agreement shall be void unless prior written approval is obtained from
         DHS and/or such Medi-Cal Plan."


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IN WITNESS WHEREOF, the parties have caused this Assignment and Amendment to be
executed by their respective duly authorized representatives as of the date set
forth below.

THE PERMANENTE MEDICAL GROUP INC.

By: /s/ Dennis Ing
   ----------------------------------------------------
   Dennis Ing, M.D., Director of Services Planning
   TPMG Medical Services Planning & Contracting

Date: 8/28/00
     --------------------------------------------------


Reviewed By: /s/ Bellinda Rossmiller
            -------------------------------------------
   Bellinda Rossmiller, Administrator
   Med. Svcs. Planning & Contracting Support

Date: 8/30/00
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RADIATION ONCOLOGY MEDICAL GROUP, INC.

By:      /s/ Harry Newman
   ----------------------------------------------------
Name:    Harry Newman, M.D.
     --------------------------------------------------
Title:   President
      -------------------------------------------------
Date:    8/30/00
     --------------------------------------------------


USCC MEDICAL GROUP - CA, INC.

By:      /s/ Barry Tepperman
   ----------------------------------------------------
Name:    Barry J. Tepperman, M.D.
     --------------------------------------------------
Title:   Medical Director
      -------------------------------------------------
Date:    8/31/00
     --------------------------------------------------


USCC HEALTHCARE MGT. CORP.
By:      /s/ R. W. Padelford
   ----------------------------------------------------
Name:    Richard W. Padelford
     --------------------------------------------------
Title:   President
      -------------------------------------------------
Date:    9/1/00
     --------------------------------------------------


USCMC-USCC PARTNERSHIP
By:      US Cancer Management Corp. Managing Partner
   ----------------------------------------------------
Name:    By W. Brian Fuery
     --------------------------------------------------
Title:   President
      -------------------------------------------------
Date:    8/28/00
     --------------------------------------------------