187P - More is not always better: A multicenter study in lymphadenectomy during gastrectomy for gastric neuroendocrine carcinoma

Background

Few reports address the impact of surgery on the prognosis of rare and heterogeneous gastric neuroendocrine carcinoma (G-NEC). This study analyzed the influence of surgical treatments on prognosis to provide a personalized surgical treatment strategy for G-NEC patients.

Methods

The clinicopathological data of 964 G-NEC patients from 24 Chinese hospitals were analyzed. Cox regression analyses were used to analyze the prognostic factors affecting survival and recurrence, respectively.

Results

Cox analysis revealed that in stage I-II but not stage III gastric neuroendocrine carcinoma/mixed adenoneuroendocrine carcinoma (NEC/MANEC) patients, D2 (extended) lymph node dissection (ELND) was an independent protective factor for OS and DFS (p<0.05; p<0.05). In stage I-II, 3-year OS and DFS increased with more of LNs dissected (p<0.05), while in stage III patients undergoing ELND, the 3-year OS and DFS was similar to patients undergoing D1+ (limited) lymph node dissection (LLND) (p>0.05). Furthermore, among patients with stage III disease, the incidence of complications after ELND was significantly greater than that after LLND (28.4% vs. 12.1%, p < 0.001), especially severe complications (Clavien-Dindo grade III-V). For patients with stage I-II disease, ELLN not only brings lower overall recurrence rate (ELND vs. LLND = 16.9% vs 27.6%, p = 0.018) but also reduced the risk of regional LN and distant LN recurrence (all p < 0.05).

Conclusions

ELND may lead to enhanced long-term survival for stage I and II but not stage III NEC/MANEC patients. Our results in multicenter patients do not support the routine use of ELND in stage III NEC/MANEC patients.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Scientific and Technological Innovation Joint Capital Projects of Fujian Province.

Disclosure

All authors have declared no conflicts of interest.