Pathologic exploration of neuroendocrine differentiation in carcinomas.

Abstract

e16238 Background: Tumor with neuroendocrine differentiation (NED) has been verified in non-neuroendocrine organ adenocarcinomas. However, the incidence of NED in various studies varies greatly due to the different selection and criteria of NED markers. Further analysis of large clinical samples is still needed to reveal its biological characteristics and clarify the diagnosis and treatment of NED. Methods: From January 2017 to June 2018，a total of 450 histopathological samples were collected and analyzed retrospectively from patients with multiple malignant cancers, including gastric cancer (GC), colorectal cancer (CRC), lung cancer, breast cancer and prostate cancer treated in Cancer Hospital, Chinese Academy of Medical Sciences. Immunohistochemical staining for NED markers such as synaptophysin (Syn), chromogranin A (ChrA), and neural cell adhesion molecule (CD56) were performed to explore the incidence of different cancer types. Furthermore, NED or non-NED patients were evaluated comparatively in terms of pathological characteristics and prognosis. Results: Up to February 6, 2023, 129 CRC and GC samples were measured. 9 (15.3%) of 59 CRC patients were positive for NED markers, including 7 cases of Syn (+), 6 cases of ChrA (+) and 2 cases of CD56 (+). Moreover, 4 (6.8%) of 59 patients were positive for at least 2 NED markers in CRC. 18 (52.9%) of 34 gastric signer ring cell carcinoma patients were positive for NED markers, including 15 cases of Syn (+) and 14 cases of ChrA (+). Meanwhile, 10 (27.8%) of 36 gastric tubular adenocarcinoma patients were positive for NED markers, including 6 cases of Syn (+) and 10 cases of ChrA (+). Particularly, 17 (24.3%) (11/6, signer ring cell carcinoma/ tubular adenocarcinoma) of 70 GC patients were positive for at least two NED markers. Conclusions: NED is widely present in colorectal cancer and gastric cancer, especially in gastric signer ring cell carcinoma. The encouraging outcomes of the NED prevalence rate may shed light on the individualized treatments for patients with carcinomas. Further explorations are needed in the following research. [Table: see text]