Manual versus image analysis estimation of PCNA in breast carcinoma

OBJECTIVE: To compare manual to image analysis estimation of proliferating cell nuclear antigen (PCNA) expression in paraffin sections of breast carci nomas. STUDY DESIGN: Paraffin sections of 51 breast carcinomas were stained with p rimary antibody to PCNA. Nuclear PCNA expression in 100 randomly Selected t umor cells from marked areas was manually graded from 0 to 3. Antigen expre ssion was also calculated by a cell analysis system (CAS-200, Becton Dickin son, Elmhurst, Illinois, U.S.A.)from marked and random microscopic fields. Obtained proliferative inner (PI) from both methods was compared. RESULTS: Manually calculated PI correlated strongly with the CAS-200-calcul ated PI (P <.01). The highest correlation was seen between the CAS-200 PI v alue and manually calculated PI value using grade 2 and 3 nuclei. A particu larly high correlation was noted between the number of positive nuclei and antigen staining area (P <.01) as estimated by the CAS-200. CONCLUSION: Nuclear expression of PCNA and other nuclear antigens can be ac curately evaluated by an image analysis system. The speed and objectivity o f such machines allow the evaluation of larger parts of tissues and provide more-representative antigen expression profiles.