Histopathologic features of atypical glands on prostate biopsy: Nucleolar size is a predictor of subsequent detection of prostatic adenocarcinoma

Abstract

Patients whose prostate biopsy reveals the presence of atypical glands suspicious for carcinoma (AGSC) are subject to close monitoring and repeat biopsies, perhaps unnecessarily, as clinicians do not have a clear basis for understanding and stratifying the significance of these findings. In a retrospective, blinded manner, we histopathologically examined initial biopsies reported as AGSC (82 patients, 93 foci). On subsequent biopsies, 31 (38%)/5 (6%) patients were found to have prostate cancer (PCA)/AGSC, respectively, while no carcinoma (NOCA) was identified in the remainder (56%) of cases. Nucleolar grade (on a scale of 1-4 with "1" denoting small, inconspicuous nucleoli and "4" denoting macronucleoli) was significantly higher in PCA cases than in NOCA cases whether comparing all AGSC foci (P = 0.006) or when considering the highest grade in each patient (P = 0.009). However, the number of AGSC per focus was similar (P = 0.926) between PCA (mean ± SD: 7.03 ± 5.35) and NOCA (mean ± SD: 7.13 ± 4.44). Adjacent (P = 0.117) and separate (P = 0.457) high-grade prostatic intraepithelial neoplasia was found in 8/37 (22%) foci and 12/31 (39%) cases in PCA, respectively, and in 4/48 (8%) foci and 13/46 (28%) cases in NOCA, respectively. The presence of intraluminal dense secretion, crystalloid, or mucin in AGSC did not show a statistically significant correlation between PCA [5/37 (14%)] and NOCA [10/48 (21%)] (P = 0.567). Our study may thus clarify the significance of AGSC on prostate biopsy and suggests that the size of nucleoli in AGSC is a positive predictor of subsequent detection of prostatic adenocarcinoma.