Gastric adenocarcinoma with neuroendocrine differentiation: Clinicopathological features and efficacy of modified DCF chemotherapy.

PURPOSE: The aim of this study was to investigate the clinicopathological characteristics of patients with gastric carcinoma with neuroendocrine differentiation (NEDGC) and the efficacy of the modified DCF (mDCF) chemotherapy regimen.

METHODS: Patients with NEDGC and non-NEDGC (pure adenocarcinoma) were evaluated comparatively in terms of pathological parameters, clinical parameters and treatment efficacy. Patients received treatment with mDCF (docetaxel, cisplatin and 5-fluorouracil).

RESULTS: In total, 391 patients (35 with NEDGC and 356 with non-NEDGC) were included in this study. In particular, in the NEDGC group, the presence of lymphovascular invasion (LVI), presence of perineural invasion (PNI), median tumor size, and metastasis at the time of diagnosis were significantly higher than in the non-NEDGC group. mDCF was used as first-line chemotherapy regimen in 16 patients in the NEDGC group, and in 151 patients in the non-NEDGC group. In NEDGC and non-NEDGC groups overall disease control rate was 87.5% [partial response (PR) (50.0%), stable disease (SD) (37.5%)] and 80.8% [complete response (CR) (2.6%), PR (38.4%), SD (39.8%)], respectively. In the advanced-stage patients who had first-line mDCF, the median overall survival (OS) was 10.6 months (95% CI: 5.9-15.4) and 12.2 months (95% CI: 10.3-14.2) in NEDGC and non-NEDGC groups, respectively (p=0.88). The median progression-free survival (PFS) in the NEDGC and the non-NEDGC groups were 7.6 months (95% CI: 5.5-9.7) and 7.5 months (95% confidence interval/CI: 6.8-8.1), respectively (p=0.82).

CONCLUSION: NEDGC patients usually have higher LVI and PNI rates, and they present with advanced disease. In this group of patients, mDCF regimen may be an effective treatment option. However this statement needs to be verified by further prospective and multi-centered studies including a larger patient cohort.