KI-67 EXPRESSION IN EARLY PROSTATE-CANCER AND ASSOCIATED PATHOLOGICALLESIONS

Aim-To assess cell proliferation in early prostate cancer and associat ed pathological lesions. Methods-Using the Ki-67 antibody, the cell pr oliferation index was measured in early stage prostatic carcinoma in 3 7 incidental tumours diagnosed at transurethral prostatectomy (TURP) a nd in 20 low volume cancers treated by radical prostatectomy. Prolifer ation indexes have also been measured in areas of normal peripheral zo ne, transition zone hyperplasia, atrophic appearing lobules, and high grade prostatic intraepithelial neoplasia in the radical prostatectomy cases. Results-In the TURF series the proliferation index correlated with grade and stage. Logistic regression analysis, however, showed th at Gleason grade was the most reliable predictor of biopsy proven resi dual disease and clinical progression. In the radical series transitio n zone carcinoma the proliferation index was half that of peripheral z one carcinoma. The atrophic lobules also showed a high proliferation i ndex of the same order as seen in the peripheral zone carcinoma. Norma l peripheral zone showed the lowest proliferation index and in hyperpl astic transition zone it was also less than the other areas. Conclusio ns-There is only limited support for the correlation of proliferation index with grade in early stage prostatic carcinoma. The findings do n ot suggest that proliferation index adds to the prognostic information given by grade and stage in pT1 disease. The significant difference i n proliferation index in transition zone and peripheral zone carcinoma s supports the morphological distinction of these tumour types and is consistent with differences in biological behaviour. The high prolifer ation index in lobules considered morphologically atrophic is reminisc ent of previous observations in which carcinoma was spatially associat ed with atrophy.