MINIMAL CARCINOMA IN PROSTATE NEEDLE-BIOPSY SPECIMENS - DIAGNOSTIC FEATURES AND RADICAL PROSTATECTOMY FOLLOW-UP

Prostate cancer screening and early detection efforts have resulted in the identification of smaller volume carcinomas of the prostate. We e valuated the diagnostic features of minimal (< 1 mm) carcinoma in sext ant needle biopsy specimens of the prostate and in follow-up analyzed the features of the corresponding carcinomas Bn the whole gland. We re viewed specimens from 50 consecutive patients who had minimal carcinom a in needle biopsy tissue and who had undergone radical prostatectomy. Histologic grade, tumor size, pathologic stage, and margin status of the 50 carcinomas in the whole gland in which the carcinoma size was m inimal in the sextant needle biopsy specimen were compared with those of 50 carcinomas in the whole gland in which carcinoma size was greate r than 1 mm in the needle biopsy specimen. The most common morphologic features of these minimal carcinomas were nucleomegaly (96%), infiltr ative growth pattern (88%), intraluminal secretions (78%), prominent n ucleoli (64%), associated high-grade prostatic intraepithelial neoplas ia (40%), amphophilic cytoplasm (36%), hyperchromatic nuclei (30%), an d intraluminal crystalloids (22%). Perineural invasion (2%), collageno us micronodules (2%) and mitotic figures (2%) were uncommon. The mean tumor volume in the whole gland of carcinomas corresponding to minimal carcinoma in a needle biopsy specimen was significantly smaller (P = .029) at 1.1 mt than it was in carcinomas with tumor greater than 1 mm in the needle biopsy specimen at 1.6 mi, but other pathologic feature s of carcinoma in the whole gland were not significantly different. In conclusion, a constellation of morphologic attributes is important fo r establishment of a diagnosis of minimal carcinoma of the prostate in needle biopsy specimen. Most (82%) of the corresponding prostate canc ers in the whole gland were pathologically significant.