Correlation between histopathological form and the degree of neuroendocrine differentiations in prostate cancer.

Prostate cancer (PCa) is the most frequent neoplasic condition in males, but only 64-65% of the cases are sensitive to hormone therapy. The aim of this study was to investigate the neuroendocrine component of the prostatic carcinoma, in relation to the histopathological form and the degree of differentiation. Biopsies were obtained through transurethral resection, from 82 patients with prostate cancer. In order to assess the histopathological form and the Gleason score, one section from each case was stained with Hematoxylin-Eosin. Additional sections were stained with chromogranin A. We considered neuroendocrine cell hyperplasia to have a higher value than that observed in benign prostatic hyperplasia (BPH) and normal prostate (over three neuroendocrine cells÷gland). The quantification of neuroendocrine differentiation (NED) has been significant; the reaction was considered to be weak (2-10% neuroendocrine cells), moderate (10-20%) and intense (over 50%). Cells positive for chromogranin A have been identified in all the cases, but a larger number than that registered in normal tissue has been noted in 59 patients (71.95%). In most of the cases, the neuroendocrine cells have been distributed in small groups among the neoplasic cells, and rarely isolated. In two cases of small cell carcinoma most of the tumoral cells have been positive for chromogranin A. In conclusion, the study of neuroendocrine differentiation in patients with prostatic carcinoma revealed hyperplasia of positive chromogranin A cells, in 71.95% of cases. Neuroendocrine prostatic differentiation is correlated with the advanced stage of evolution and possibly with the resistance to hormonal treatment.

VEGF expression in dog mastocytoma.

UNLABELLED: The biologic behavior of mastocytomas is highly variable; some tumors have a benign behavior, whereas others exhibit aggressive growth and metastasis. Vascular endothelial growth factor (VEGF) is a major regulator of angiogenesis and a potential autocrine growth factor for neoplastic cells in various malignancies. MATERIAL AND METHOD: In the present study, we have investigated expression of VEGF in cutaneous tumor from a dog and combined immunohistochemical expression of VEGF with mast cell tryptase, CD117 and vimentin. RESULTS: Tumor cells were positive for VEGF, and inflammatory cells were negative. VEGF expression was found in tumor cells as a heterogeneous positive reaction, with cytoplasmic pattern and moderate to strong in intensity. Arrangement of tumor cells was in clusters, in deepest part, close to the proliferation front. The dog died 5 month from the diagnosis, and our observation suggest that VEGF secretion by tumor cells correlates with unfavorable prognosis.