Surgical Outcomes and Survival Prognostic Factors for Palliative Gastrectomies in Stage IV Resectable Gastric Cancer Outlet Obstruction Patients

Role of reduction gastrectomy in patients with gastric cancer with a single non-curable factor: Supplementary analysis of REGATTA trial

Background

REGATTA trial failed to demonstrate the survival benefit of reduction gastrectomy in patients with advanced gastric cancer with a single non-curable factor. However, a significant interaction was found between the treatment effect and tumor location in the subset analysis. Additionally, the treatment effect appeared to be different between Japan and Korea. This supplementary analysis aimed to elucidate the effect of reduction surgery based on tumor location and country.

Methods

Multivariable Cox regression analyses in each subgroup were performed to estimate the hazard ratio (HRadj), including the following variables as explanatory variables: country, age, sex, incurable factor, cT, cN, primary tumor, performance status, histological type, and macroscopic type.

Results

Patients (95 in Japan and 80 in Korea) were randomized to chemotherapy alone (86 patients) or gastrectomy plus chemotherapy (89 patients). The subgroup analysis according to the country revealed a worse overall survival in gastrectomy plus chemotherapy arm in Japan (hazard ratio: 1.32, 95% confidence interval: 0.85-2.05), but not in Korea (hazard ratio: 0.85.95% confidence interval: 0.52-1.40). Overall survival was better in distal gastrectomy plus chemotherapy compared with chemotherapy alone (hazard ratio = 0.69, 95% confidence interval: 0.42-1.13), and worse in total gastrectomy plus chemotherapy compared with chemotherapy alone (hazard ratio = 1.34, 95% CI: 0.93-1.94), which was more remarkable in Korea than in Japan.

Conclusions

Primary chemotherapy is a standard of care for advanced gastric cancer; however, the survival benefits from reduction by distal gastrectomy remained controversial.

Development and verification of a nomogram for predicting the prognosis of resectable gastric cancer with outlet obstruction

Background

The prognosis of patients with gastric cancer (GC) with gastric outlet obstruction (GOO) after gastrectomy is highly variable. In this study, we aimed to develop a nomogram to predict the prognosis of these patients.

Patients and Methods

Data from 218 GC patients with GOO who underwent gastrectomy at Sun Yat-sen University Cancer Center were retrospectively collected as a training cohort. The data of 59 patients with the same diagnosis who underwent gastrectomy at the First Affiliated Hospital of Guangxi Medical University were collected as an external verification cohort. A nomogram for the overall survival (OS) was developed using the Cox regression model in the training cohort, which was validated in a verification cohort.

Results

Multivariate analysis showed that the surgical procedure (P < 0.001), period of chemotherapy (P < 0.001), T stage (P = 0.006), N stage (P = 0.040), systemic immune-inflammatory index (SII) (P < 0.001), and fibrinogen level (P = 0.026) were independent factors affecting OS. The nomogram constructed on the aforementioned factors for predicting the 1- and 3-year OS achieved a Harrell’s concordance index (C-index) of 0.756 and 0.763 for the training and verification cohorts, respectively. Compared with the 8th American Joint Committee on Cancer (AJCC) Tumour-Node-Metastasis (TNM) staging system, the nomogram had higher C-index values and areas under the curve (AUCs) and slightly higher net clinical benefit.

Conclusion

Compared to the 8th AJCC staging system, the newly developed nomogram showed superior performance in predicting the survival of GC patients with GOO after gastrectomy.