Exhibit 10.33
                              DIANON SYSTEMS, INC.

                                                            Grant No.

                               STOCK OPTION GRANT


Optionee:               Andre deBruin        Total No. of Shares          10,000

Date of Grant:              10/24/1996       Exercise Price Per Share     $7.125

Termination Date:           10/23/2006                                $71,250.00


     DIANON  SYSTEMS,  INC.  (the  "Company")  has this day granted to you,  the
optionee  named  above,  an option  to  purchase  shares of common  stock of the
Company  ("Common  Stock").  This option is granted in replacement of the option
which was previously granted to you on June 4, 1993.

     The details of your option are as follows:

     1. The total number of shares subject to this option is as set forth above.
Subject to the limitations contained herein, this option shall be exercisable on
or after the date of the vesting of such option as follows:



     Percentage of Shares              Date of Earliest Exercise (Vesting)
     --------------------              -----------------------------------

                                                
            100%                                   10/24/96


     2. (a) The per share  exercise  price of this option is as set forth on the
face of this option grant,  and is the same as the exercise  price of the option
granted to you on June 4, 1993 which this option replaces.

        (b) Payment of the exercise price is due in  full in cash upon  exercise
when the  aggregate  option  exercise  price for the shares  being  purchased is
$2,500 or less;  but when the  aggregate  exercise  price for the  shares  being
purchased  exceeds  $2,500,  you may elect to make payment of the exercise price
under one of the following alternatives:

               (i)  Payment  of the  exercise  price  in cash at the time of the
          exercise;

               (ii) (a) Payment of not less than 10% of the  aggregate  exercise
          price due at the time of  exercise  in cash,  (b) not less than 10% of
          said exercise price, plus simple interest at the lowest rate which, at
          the time of exercise,  will prevent any imputation of higher  interest
          under  Section 483 of the Internal  Revenue  Code,  per year after the
          time of  exercise,  with (c) final  payment  of the  remainder  of the
          exercise  price,  plus  interest,  due five  (5)  years  from  date of
          exercise,  provided that as a part of your written  notice of exercise
          you give notice of the election of this deferred payment  arrangement,
          and to  secure  the  payment  of the  deferred  purchase  price to the
          Company  hereunder,  which such  election  you tender to the Company a
          security agreement  satisfactory to the Company covering the purchased
          shares;

               (iii) Provided that at the time of exercise the Company's  common
          stock is  publicly  traded and  quoted  regularly  in the Wall  Street
          Journal,  payment by delivery of shares of common stock of the Company
          which  you have  owned for at least six moths and which at the time of
          exercise  are  owned  by you  free and  clear  of any  liens,  claims,
          encumbrances or security interests, which common stock shall be valued
          (i) if listed on a national securities exchange or the Nasdaq national
          market,  at the average  closing  price for the ten (10)  trading days



          immediately  preceding  the date of exercise or (ii)  otherwise at the
          average of the closing bid and ask  quotations  published  in the Wall
          Street Journal for the ten (10) trading days immediately preceding the
          date of exercise; or

               (iv)  Payment in the form of any other legal  consideration  that
          may be acceptable to the Board of Directors of the Company in its sole
          discretion at the time of exercise.

     3. The minimum  number of shares  with  respect to which this option may be
exercised at any one time is one hundred (100), however, if the number of shares
subject to exercise is less than one hundred, the option must be exercised as to
all of such shares.

     4.  Notwithstanding  anything to the contrary contained herein, this option
may not be exercised unless the shares issuable upon exercise of this option are
then registered under the Securities Act of 1933, as amended (the "Act"),  or if
such shares are not then  registered,  the Company  has  determined  in its sole
discretion  that such  exercise and issuance  would be exempt from  registration
under the Act.  Your right to exercise  this option is also  conditioned  on the
Company's  listing of the shares  subject to this option on the Nasdaq  national
market or any  securities  exchange on which the Common Stock is then traded and
compliance with any applicable  securities  registration or other securities law
requirements.

     5. The term of this option  commences on the date hereof and  terminates on
the date set forth on the face of this option grant.

     6.  This  option  may  be  exercised,  to the  extent  specified  above  by
delivering  a  notice  of  exercise  together  with  the  exercise  price to the
Secretary of the Company,  or to such other person as the Company may designate,
during regular  business hours,  together with such additional  documents as the
Company may then require.

     7.  This  option  is not  transferable,  except  by will or by the  laws of
descent and distribution, and is exercisable during your life only by you.

     8. Any notices  provided  for in this option  shall be given in writing and
shall be deemed  effectively  given  upon  receipt  or,  in the case of  notices
delivered  by the  Company  to you,  five (5) days  after  deposit in the United
States mail, postage prepaid, addressed to the optionee at the address specified
below or at such other address as the optionee  hereafter  designates by written
notice delivered to the Company.

     9.  Whenever  shares are to be issued in  satisfaction  of this  option you
shall remit to the Company an amount sufficient to satisfy federal, state, local
or other  withholding  tax  requirements  if and to the extent  required  by law
(whether  so  required  to secure for the  Company an  otherwise  available  tax
deduction  or  otherwise)   prior  to  the  delivery  of  any   certificate   or
certifi-cates for such shares.

     10.  In the event of any  merger,  reorganization,  consolidation,  sale of
substantially  all  assets,  recapitalization,   stock  dividend,  stock  split,
spin-off,  split-off,  distribution  of  assets  or other  change  in  corporate
structure  affecting the Common Stock, a substitution  of adjustment,  as may be
determined  to be  appropriate  by the Board of  Directors  or the  Compensation
Committee  of the  Board  ("the  Compensation  Committee")  shall be made in the
number, option price and kind of shares covered by this Option; provided however
that no such  adjustment  shall increase or decrease the aggregate  value of any
outstanding portion of this Option.

     11. The Board of Directors and the Compensation Committee reserve the right
to  interpret  the  provisions  of  this  Option,  make  any  necessary  factual
determinations,   and  adopt,  amend,  and  rescind   administrative  rules  and
procedures in connection with the exercise of this Option. Any interpretation or
determination  by the  Board or the  Compensation  Committee  shall be final and
binding.





The undersigned:

Dated This  24th    day of         (a) Acknowledges receipt of the fore-

 October           , 1996   .      going option and understands that all
- -------------------      ---
                                   rights and liabilities connected with

                                   this option are set forth in the Option,

                                   (b) Acknowledges that as of the date

Very truly yours,                  of grant of this option, it sets
DIANON SYSTEMS, INC.
                                   forth the entire understanding
Duly authorized on
behalf of the                      between the undersigned optionee and
Board of Directors
                                   the Company regarding the acquisition of

                                       stock from the
Company and supersedes all         prior oral and written agreements on that

                                   subject with the

exception of the following         agreements only: (if none, so state)



                                    /s/ Andre deBruin
                                 ----------------------------------------

                      Address:      2545 Central Ave.
                                 ----------------------------------------

                                    Boulder, CO  80301
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