Appendiceal neuroendocrine tumors: Recent insights and clinical implications

Abstract

New insights emerged last decade that enriched our knowledge regarding the biological behavior of appendiceal neuroendocrine tumors (NETs), which range from totally benign tumors less than 1cm to goblet cell carcinomas which behave similarly to colorectal adenocarcinoma. The clinical implication of that knowledge reflected to surgical strategies which also vary from simple appendicectomy to radical abdominal procedures based on specific clinical and histological characteristics. Since the diagnosis is usually established post-appendicectomy, current recommendations focus on the early detection of: (1) the subgroup of patients who require further therapy; (2) the recurrence based on the chromogranin a plasma levels; and (3) other malignancies which are commonly developed in patients with appendiceal NETs.

The clinicopathological significance of angiogenesis in hindgut neuroendocrine tumors obtained via an endoscopic procedure

“…However, a number of recent studies have reported a higher than expected rate of venous and/or lymphatic invasion (lymphovascular invasion) in GEP-NET samples obtained via endoscopic procedures [4–6]. In a case series from our own institution, we identified a lymphovascular invasion rate of approximately 30 % for GEP-NETs.…”

A well differentiated neuroendocrine tumor of the jejunum with peritoneal carcinomatosis: A case report

“…Foregut NETs refer to tumors arising in the respiratory tract, thymus, thyroid, stomach, duodenum and pancreas. Midgut NETs develop in the small bowel, appendix and ascending colon (11), while hindgut tumors appear in the transverse, descending colon and rectum (12,13).…”

Goblet cell carcinoid of the appendix: a case report

“…Tübüler karsinoid hücrelerinin çoğu nöroendokrin özellikte iken GHKT' de hücrelerin %25'inden azı nöroendokrin özellik gösterir (3,22,23).…”

“…Olgumuz da literatürle uyumlu olarak bu özelliklere sahip değildi. GHKT 'lerde MUC2 pozitif, p53 %5-10 pozitif, MUC1 negatif iken, adenokarsinomlarda p53 pozitif, MUC1 pozitif, MUC2 % 5 pozitiftir (3,8,22,24).…”