Primary prostatic central zone adenocarcinoma

The central zone (CZ) of the prostate is embryologically, anatomically, and histologically distinct. High-grade prostatic intraepithelial neoplasia (HGPIN) and prostatic adenocarcinoma (PAC) are encountered in the CZ, but have not been well studied. Non-CZ PAC that spread into the CZ can mimic CZ PAC. We reviewed 300 consecutive radical prostatectomies performed for PAC to identify cases showing PAC and HGPIN in the CZ. There were nine PAC (3%) localized predominantly in the CZ, presenting as a single tumor nodule (8/9) and associated with 4.5±1.1 foci HGPIN in the CZ and with only 1.7±0.5 foci in the PZ. Of the 291 non-CZ PAC, 24 cases showed satellite tumor nodules in the CZ, and 92 cases demonstrated secondary contiguous spread to the CZ. As compared to the non-CZ PAC, CZ PAC tended to have lower tumor volume, but had higher Gleason scores (8.10±0.6 vs. 6.30±0.7, p