Differing Prognoses Among Gastric Cancers

Patients with gastric neuroendocrine carcinoma or gastric mixed adenoneuroendocrine carcinoma had worse prognoses and were more likely to experience distant recurrence than patients with gastric adenocarcinoma, according to a study published in JAMA Network Open. These results could provide useful medical information for the development of follow-up and treatment strategies to improve the long-term survival of patients with gastric neuroendocrine carcinoma or gastric mixed adenoneuroendocrine carcinoma.  

Gastric neuroendocrine carcinoma and gastric mixed adenoneuroendocrine carcinoma are rare types of gastric cancer. To date, there are few multicenter studies that compare the prognoses and recurrence patterns of gastric neuroendocrine carcinoma, gastric mixed adenoneuroendocrine carcinoma, and gastric adenocarcinoma.

Investigators conducted a multicenter, retrospective cohort study including patients with resectable gastric neuroendocrine carcinoma and gastric mixed adenoneuroendocrine carcinoma at 23 hospitals in China, from January 2006 to December 2016. In addition, patients with gastric adenocarcinoma were included as the control group. The study aimed to compare the differences in long-term survival and patterns of recurrence among patients with gastric neuroendocrine carcinoma, gastric mixed adenoneuroendocrine carcinoma, and gastric adenocarcinoma.  

The primary outcomes were disease-free survival (DFS) and patterns of recurrence. The researchers defined DFS as the time interval from the date of the operation to the date of recurrence or death, with evidence of recurrence.

In total, 3689 patients were included in the analysis. The median age of the study participants were 62 (interquartile range [IQR], 55-69) years, and 2748 (74.5%) were men. Overall, the analysis included 503 patients (13.6%) with gastric neuroendocrine carcinoma, 401 patients (10.9%) with gastric mixed adenoneuroendocrine carcinoma, and 2785 patients (75.5%) with gastric adenocarcinoma.

Following propensity score matching, 5-year DFS was 47.6% (95% CI, 42.7%-52.5%) for patients with gastric neuroendocrine carcinoma, compared with 57.6% (95% CI, 55.1%-60.1%) for patients with gastric adenocarcinoma (P < .001) and 51.1% (95% CI, 46.0%-56.2%) for patients with gastric mixed adenoneuroendocrine carcinoma, compared with 57.8% (95% CI, 55.1%-60.5%) for patients with gastric adenocarcinoma (P =.02).

Multivariable analysis confirmed that, compared with gastric adenocarcinoma, gastric neuroendocrine carcinoma (hazard ratio [HR], 1.64; 95% CI, 1.40-1.93) and gastric mixed adenoneuroendocrine carcinoma (HR, 1.25; 95% CI, 1.05-1.49) were independent risk factors associated with worse DFS.

Compared with matched patients with gastric adenocarcinoma, patients with gastric neuroendocrine carcinoma were more prone to distant recurrence (268 patients [17.2%] vs 101 patients [23.7%]; P =.002), as were patients with gastric mixed adenoneuroendocrine carcinoma (232 patients [17.3%] vs 76 patients [22.8%]; P =.02).

In multivariable analysis, gastric neuroendocrine carcinoma (HR, 2.22; 95% CI, 1.66-2.98) and gastric mixed adenoneuroendocrine carcinoma (HR, 1.70; 95% CI, 1.24-2.34) were found to be independent risk factors associated with distant recurrence.

In multivariable analysis, T3 to T4 stage (odds ratio [OR], 2.84; 95% CI, 1.57-5.14; P =.001) and lymph node metastasis (OR, 2.01; 95% CI, 1.31-3.10; P =.002) were found to be independent risk factors associated with distant recurrence of gastric neuroendocrine carcinoma and gastric mixed adenoneuroendocrine carcinoma.

This study had multiple limitations. The research was performed in China and, therefore, it is unclear whether these findings are generalizable to western populations. Additionally, patients with gastric adenocarcinoma were only included from 1 center, which may have generated center-related effects and caused selection bias. Finally, almost 10.0% of patients with recurrences did not have documented recurrence patterns, and these patients were not included in the recurrence pattern analysis.  

According to the data, patients with gastric neuroendocrine carcinoma or gastric mixed adenoneuroendocrine carcinoma had worse prognoses compared against patients with gastric adenocarcinoma. Gastric neuroendocrine carcinoma and gastric mixed adenoneuroendocrine carcinoma were found to be independent risk factors associated with worse DFS and distant recurrence. Patients with gastric neuroendocrine carcinoma and gastric mixed adenoneuroendocrine carcinoma were more prone to distant recurrence, particularly among patients with tumors penetrating into the subserosa or deeper layers and with lymph node metastasis.

According to the study authors, “These findings suggest that different follow-up and treatment strategies should be developed to improve the long-term survival of patients with gastric neuroendocrine carcinoma or gastric mixed adenoneuroendocrine carcinoma, especially for patients with tumors penetrating into the subserosa or deeper layers and with lymph node metastasis.

Disclosure: This research was supported by multiple sources. Please see the original reference for a full list of disclosures.

Reference

Lin J, Zhao Y, Zhou Y, et al. Comparison of survival and patterns of recurrence in gastric neuroendocrine carcinoma, mixed adenoneuroendocrine carcinoma, and adenocarcinoma. JAMA Netw Open. 2021;4(7):e2114180. doi: 10.1001/jamanetworkopen.2021.14180