Inverted (hobnail) high-grade prostatic intraepithelial neoplasia and invasive inverted pattern

High-grade prostatic intraepithelial neoplasia (HGPIN) is considered to be an important precursor for prostatic adenocarcinoma. The present study aimed to investigate the histological features of the uncommon inverted (hobnail) pattern of HGPIN in transrectal ultrasonographic (TRUS) prostatic needle biopsies from 13 cases. These 13 diagnosed cases of inverted HGPIN were identified out of a total of 2,034 TRUS biopsies (0.63%), obtained from patients suspected to have prostate cancer. The hobnail pattern is comprised of secretory cell nuclei, which are histologically localized at the luminal surface of the prostate gland, rather than the periphery, and exhibit reverse polarity. Histological examinations were performed and the results demonstrated that 5 of the 13 cases exhibited pure inverted histology, while HGPIN was observed to be histologically associated with other patterns in the remaining 8 patients. In addition, an association with adenocarcinoma was identified in 7 of the 13 cases. All 7 carcinomas accompanied by inverted HGPIN were conventional acinar adenocarcinoma cases; of note, for these 7 cases, the Gleason score was 7 for each. One acinar adenocarcinoma case accompanying inverted HGPIN demonstrated hobnail characteristics in large areas of the invasive component. It was observed that nuclei were proliferated in the invasive cribriform glands, which was comparable to that of inverted HGPIN, and were located on the cytoplasmic luminal surface; a similar morphology was also observed in individual glands. In conclusion, the results of the present study suggested that the hobnail HGPIN pattern may be of diagnostic importance due to its high association with adenocarcinoma and the high Gleason scores in the accompanying carcinomas

Primary breast carcinomas with neuroendocrine features: Clinicopathological features and analysis of tumor growth patterns in 36 cases

Primary breast carcinoma with neuroendocrine features (NEBC) is an uncommon tumor. In the classification of WHO 2012, these tumors were categorized as: 1- neuroendocrine tumor, well-differentiated; 2- neuroendocrine carcinoma, poorly differentiated/small cell carcinoma; and 3- invasive breast carcinoma with neuroendocrine differentiation. In this study, we reviewed NEBC except poorly differentiated/small cell carcinoma variant in order to define the morphological growth patterns and cytonuclear details of these tumors. All breast surgical excision materials between 2007 and 2016 were re-evaluated in terms of neuroendocrine differentiation. Thirty-six cases showing positive staining for synaptophysin and/or chromogranin A in >= 50% of tumor cells were included in the study. All cases were female with a mean age of 67.4. Mean tumor diameter was 26 mm. Multifocality was noted in 5 cases. Grossly, they were mostly infiltrative mass lesions. T stages, identified in 34 cases, were as follows: 13 cases with pTl; 19 pT2 and 2 pT3. We described schematically 4 types of patterns depending on predominant growth pattern, except one case: 1) Large-sized solid cohesive groups (6 cases), 2) Small- to medium-sized solid cohesive groups with trabeculae/ribbons and glandular structures (6 cases), 3) Mixed growth patterns (20 cases), 4) Invasive tumor with prominent extracellular and/or intracellular mucin (3 cases). The tumor cells were mostly polygonal-oval with eosinophilic/eosinophilic-granular cytoplasm. The nuclei of tumor cells were mostly round to oval with evenly distributed chromatin. Only 5 cases showed high grade nuclear and histological features. Molecular subtypes of the cases were as follows: 33 luminal A, 2 luminal B, and 1 triple negative. NEBC should come to mind when a tumor display one of the morphological patterns described above, composed of monotonous cells with mild to moderate nuclear pleomorphism and abundant eosinophilic/eosinophilic granular or clear cytoplasm, especially in elderly patients