DIANON SYSTEMS, INC. REPORTS SECOND QUARTER SALES AND EARNINGS.

STRATFORD, Conn.--(BUSINESS WIRE)--August 10, 1995--DIANON Systems, Inc. (NASDAQ:DIAN) today reported that sales for the second quarter ended June 30, 1995 were $11,384,000 up $976,000 or 9% over the second quarter of 1994. Loss from operations was $(643,000) down $1,372,000 or 188% from the second quarter of 1994. This loss includes $1,349,000 of amortization of intangible assets, international restructuring reserves, write-downs of certain stock positions and additional severance charges. Net loss was $(353,000) down $781,000 or 183% from the second quarter of 1994. Earnings/(loss) per share were $(.07) compared to $.08 in the second quarter of 1994.

Sales for the first half were $21,866,000 up $2,208,000 or 11% over the first half of 1994. Loss from operations was $(373,000) down $1,565,000 or 131% from the first half of 1994. Net loss was $(197,000) down $867,000 or 129% from the first half of 1994. Earnings/(loss) per share were $(.04) compared to $.13 in the first half of 1994. -0-

                                             SIX MONTHS ENDED
                                                 JUNE 30
                                        1995             1994          %

Net Sales                          $21,866,000      $19,658,000       11%

Gross Profit                        12,229,000       11,701,000        5%
  % to Sales                               56%              60%

Income/(Loss) from Operations         (373,000)       1,192,000     (131%)

Net Interest Income/Expense             25,000          (73,000)      N/A

Pre-Tax Income                        (348,000)       1,119,000     (131%)

Net Income/(Loss)                     (197,000)         669,000     (129%)

Primary and Fully Diluted
  Earnings/(Loss) Per Share             $(0.04)           $0.13     (131%)

Dick Sandberg, Chairman of the Board, said, "Second quarter sales were the highest quarterly sales in Company history. Without charges for amortizing intangible assets, restructuring international operations, adjusting Aprogenex stock values, and accounting for future severance costs, earnings per share would have been $.08 for the quarter and $.16 for the first half versus $.09 and $.15 for the respective periods last year."

"During the quarter we accelerated the write-off of the customer list we acquired from Molecular Oncology, Inc. The decline in this portion of our tissue testing business continues and it is managementUs judgment that the value of this asset should be adjusted to reflect the realities of the marketplace. In addition, we have taken charges of (1) $228,000 to reflect the difference between the cost of our Aprogenex stock position and its fair market value at June 30, 1995, (2) $118,000 for the costs involved in closing or selling most of our European operations, and (3) $92,000 of additional charges relating to severance costs. Despite these charges, we still expect the Company to report a profit for the entire year."

"The Employee Stock Purchase Plan was approved by shareholders at the annual meeting. As a result, the Board of Directors has authorized the purchase of up to 300,000 shares of common stock in the open marketplace over the next two years."

DIANON Systems, Inc. is a leading provider of specialized cancer and genetic testing services and integrated information products to cancer treating physicians, cancer diagnosis specialists and managed care organizations.

CONTACT: DIANON Systems, Inc., Stratford

Richard A. Sandberg, 203-381-4022