Premalignant lesions of prostate and their association with nodular hyperplasia and carcinoma prostate

A relatively new development in the arena of prostatic histopathological study is the premalignant proliferative changes in the glandular epithelium, possibly relating to carcinoma. Two major categories have come up, namely prostatic intraepithelial neoplasia (PIN) and atypical adenomatous hyperplasia (AAH).

The aims of present study were to identify foci of the two putative premalignant conditions viz. PIN and AAH in ducto-acinar lining epithelia of 200 prostatectomy specimens and their association with nodular hyperplasia and adenocarcinoma prostate.

Micro sections from 200 prostatectomy specimens, received in the Department of Pathology, PGIMS, Rohtak, were extensively studied for the presence and association of premalignant conditions. Significant values were obtained by employing Chi-square (chi2) test, with P value < 0.05 as significant.

Out of 177 cases of nodular hyperplasia, 53 (29.9%) showed PIN and 38 (20.3%) showed presence of AAH. All 6 cases (100%) of pure carcinoma revealed foci of PIN. Out of the remaining 23 cases of carcinoma with nodular hyperplasia, foci of PIN were observed in 16 cases (94.1%) and AAH in 2 cases (11.7%). High-grade PIN was observed in 20 cases (86.9%) of the total 23 cases of carcinoma, with/without nodular hyperplasia and 20 cases (11.2%) of nodular hyperplasia. Low-grade PIN was observed in 33 cases (18.6%) of nodular hyperplasia and in only 1 case (5.8%) of carcinoma prostate with nodular hyperplasia.

PIN, especially high-grade type was the most commonly observed premalignant lesion, in cases of adenocarcinoma, thereby suggesting it to be the likely precursor of carcinoma prostate. AAH showed a weaker association with carcinoma.