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                                                                    EXHIBIT 3.65

                                                                FILED
                                                        In the Office of the
                                                     Secretary of State of Texas

                                                             OCT 31 2000

                                                        Corporations Section

                            ARTICLES OF INCORPORATION
                                       OF
               ARLINGTON PATHOLOGY ASSOCIATION 5.01(A) CORPORATION

     I, the undersigned natural person of eighteen (18) years or more, acting as
incorporator of a corporation under the Texas Non-Profit Corporation Act (the
"Act"), do hereby adopt the following Articles of Incorporation for ARLINGTON
PATHOLOGY ASSOCIATION 5.01(A) CORPORATION

                                   ARTICLE ONE

     The name of the corporation is ARLINGTON PATHOLOGY ASSOCIATION 5.01(A)
CORPORATION.

                                   ARTICLE TWO

     The corporation is a non-profit corporation.

                                  ARTICLE THREE

     The period of the corporation's duration is perpetual.

                                  ARTICLE FOUR

     The corporation is organized and shall be operated exclusively to carry out
one or more of the following purposes:

     (a)  Conducting scientific research and research projects in the public
          interest in the fields of medical sciences, medical economics, public
          health, sociology, and related areas;

     (b)  Supporting medical education in medical schools through grants and
          scholarships;

     (c)  Improving and developing of the abilities of individuals and
          institutions studying, teaching, and practicing medicine,

     (d)  Delivering health care to the public;

     (e)  Engaging in the instruction of the general public in the area of
          medical science, public health, and hygiene and related instruction
          useful to the individual and beneficial to the community; and

     (f)  Conducting other activities useful or appropriate to the
          accomplishment of the foregoing purposes.

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                                  ARTICLE FIVE

     The name and street address of the registered agent and office of the
corporation is Corporation Service Company, d/b/a CSC - Lawyers Incorporating
Service Company, 800 Brazos, Austin, Texas 78701.

                                   ARTICLE SIX

     Except as otherwise provided in these Articles of Incorporation and in the
Bylaws of the corporation, the direction and management of the affairs of the
corporation and the control and disposition of its assets shall be vested in a
board of directors (the "Board of Directors") composed of such number of persons
(but not less than three) as may be fixed by the Bylaws of the corporation. The
authority of the Board of Directors shall be limited to the extent expressly set
forth in these Articles of Incorporation and in the Bylaws of the corporation.
The number of Directors presently constituting the Board of Directors is three.
The names and addresses of the persons who shall serve as the initial Directors
of the corporation are as follows:

          NAME                               ADDRESS

          Stephen Aldred, M.D.               4350 Alpha Road
                                             Dallas, Texas 75244

          Clay J. Cockerell, M.D             2330 Butler Street, Suite 115
                                             Dallas, Texas 78235

          Joseph A Sonnier, MD               4350 Alpha Road
                                             Dallas, Texas 75244

     The initial Board of Directors have been selected in a manner consistent
with the mission, goals, and purposes of the corporation.

     Each Director shall hold office for the term for which he or she is
elected, except that the initial Directors of the corporation named in these
Articles of Incorporation shall hold office for the terms specified in the
Bylaws of the corporation to be held by such Directors, and until his or her
successor shall have been duly elected and qualified unless such Director is
sooner removed in the manner provided in the Bylaws of the corporation or he or
she resigns or dies.

     Each Director and Successor Director shall at all times be a physician duly
licensed to practice medicine by the Texas State Board of Medical Examiners (the
"TSBME") and actively engaged in the practice of medicine For purposes of these
Articles of Incorporation, the term "actively engaged in the practice of
medicine" shall be as defined by the TSBME.

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                                  ARTICLE SEVEN

     The corporation shall have one Member These Articles of Incorporation and
the Bylaws of the corporation shall define the voting rights, powers, and
privileges of the Member.

                                  ARTICLE EIGHT

     The initial Bylaws of the corporation shall be adopted by the Board of
Directors. The Articles of Incorporation and the Bylaws may be altered, amended,
or repealed, and new and other Bylaws may be made and adopted only by the
Member; provided, however, any alteration, amendment, or repeal of the Bylaws
must be approved by a majority of the Board of Directors then in office

                                  ARTICLE NINE

     The power to dissolve the corporation in accordance with the Act shall be
vested solely in the Member, following consultation with the Board of Directors

                                   ARTICLE TEN

     Any action required to, or which may, be taken at a meeting of the Member
or Directors of the corporation or a committee of the Board of Directors may be
taken without a meeting if a consent in writing, setting forth the action to be
taken, is signed by the Member, or a sufficient number of Directors or committee
members as would be necessary to take that action at a meeting at which the
Member or all of the Directors or committee members were present and voted,
provided such consent is in the form provided for and such action is taken in
accordance with the Act, these Articles of Incorporation, and the Bylaws of the
corporation

                                 ARTICLE ELEVEN

     Pursuant to Article 6.02, Subsection (3) of the Act, upon dissolution of
the corporation in accordance with the laws of the State of Texas, the Board of
Directors, after paying or making provision for payment of all liabilities of
the corporation, and after returning, transferring, or conveying those assets of
the corporation that are held subject to conditions requiring such return,
transfer, or conveyance, shall distribute all the corporation's remaining assets
as the Board of Directors in its sole discretion shall determine. Without
limiting the foregoing, the Board of Directors shall have the right to
distribute the corporation's remaining assets to one or more entities that are
not tax-exempt.

                                 ARTICLE TWELVE

     A Director or committee member of the corporation shall not be liable to
the Corporation for monetary damages for an act or omission in the Director's
capacity as a Director, except that

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this Article Twelve does not eliminate or limit the liability of a Director of
the corporation to the extent the Director is found liable for: (i) a breach of
the Director's duty of loyalty to the corporation or its Member; (ii) an act or
omission not in good faith that constitutes a breach of duty of the Director to
the corporation or an act or omission that involves intentional misconduct or a
knowing violation of the law; (iii) a transaction from which the Director
received an improper benefit, whether or not the benefit resulted from an action
taken within the scope of the Director's office; or (iv) an act or omission for
which the liability of a director is expressly provided by an applicable
statute. If the Texas Miscellaneous Corporation Laws Act or any other statute of
the State of Texas hereafter is amended to authorize the further elimination or
limitation of the liability of the Directors of the corporation, then the
liability of a Director of the corporation shall be limited to the fullest
extent permitted by the statutes of the State of Texas, as so amended, and such
elimination or limitation of liability shall be in addition to, and not in lieu
of, the limitation on the liability of a Director of the corporation provided by
the foregoing provisions of this Article Twelve. Any repeal of or amendment to
this Article Twelve shall be prospective only and shall not adversely affect any
limitation on the liability of a Director of the corporation existing at the
time of such repeal or amendment.

                                ARTICLE THIRTEEN

     The name and business address of the physician incorporator is:

     NAME                                    ADDRESS

     Joseph A Sonnier, M.D.                  4350 Alpha Road
                                             Dallas, Texas 75244

     IN WITNESS WHEREOF, I have hereunto set my hand on this 10 day of OCT.
2000.

     /s/  Joseph A. Sonnier
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     Joseph A. Sonnier, M.D., Incorporator