Management of primary gastric small cell carcinoma in China

Abstract

Background: Primary gastric small cell carcinomas (GSCCs) are increasingly identified by endoscopy, and account for 15-20% of all gastric neuroendocrine tumors (NETs). GSCCs have the worst prognosis with the highest rate of metastases.

Purpose: To provide useful information for clinicians and researchers to better manage patients with GSCC, we studied the clinical features of GSCC and explored the corresponding therapies and prognosis.

Methods: A literature search was conducted through PUBMED, EMBASE, CNKI and WanFang Databases using search terms "stomach" or "gastric" and "small cell carcinoma" or "poorly differentiated neuroendocrine carcinoma", for the period 1999 to 2012. And the cases reported were all from China. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles.

Results: Two hundred and five eligible cases were analyzed. The median age of patients was 62 years, with a male-to-female ratio of 5.4:1. Of the tumors, 53.17% were located in the upper stomach, 25.37% in the mid, 18.54% in the distal stomach, the remaining 2.93% were found in the total stomach. The mean size was 68mm in maximum diameter, with a range of 15-150 mm. Of the one hundred and thirty-five patients, fifty appeared to be pure GSCCs, eighty-five were mixed. The median overall survival time of 195 patients was 18.50 months. The 1-, 2-, and 5-year average survival rates of 142 patients were 66.75%, 37.13%, and 20.15%, respectively.

Conclusions: GSCC is a rare tumor and it is notoriously aggressive with a strong propensity for both regional and distant spread. Therapies including surgical resection, chemotherapy, and local radiotherapy, by itself or in combination with other treatment, have been used to treat GSCCs in China. To identify the most effective treatment modalities for GSCCs, we still need prospective, multicenter, randomized clinical researches.

Keywords: Small cell carcinoma; gastric; poorly differentiated neuroendocrine carcinoma; stomach.

Figure 1

A. Histopathological appearance of gastric small cell carcinoma in the pure type; B. Histopathological appearance of adenocarcinoma and small cell carcinoma components in the mixed type; C. Immunohistochemistry for synaptophysin of gastric small cell carcinoma showing diffuse positivity; D. The gastric small cell carcinoma component was strongly positive for Ki67. (A, H&E staining, original magnification 10×20; B, The mixed type 10×20; C, Synaptophysin, 10×40; D, Ki67, 10×40).