Shorter Survival of Patients with Upper-Third Gastric Cancer Preoperatively Diagnosed as Stage IA Compared with Those with Middle to Lower Lesions

Comparison of the Prognosis of Upper-Third Gastric Cancer With That of Middle and Lower-Third Gastric Cancer

PURPOSE

Gastric cancer is one of the most common cancers in Korea, and the proportion of upper-third gastric cancers has been steadily increasing over the last two decades. This study aimed to evaluate the effect of tumor location on gastric cancer prognosis.

MATERIALS AND METHODS

We retrospectively reviewed 2,466 patients who underwent gastrectomy for pathologically proven gastric cancer between January 2011 and December 2016. The patients were divided into an upper-third group (U group; n=419, 17.0%) and a middle- and lower-third group (ML group; n=2,047, 83.0%). Clinicopathological characteristics, overall survival (OS), and recurrence-free survival (RFS) after surgery were compared.

RESULTS

The U group had more advanced disease than the ML group and a higher incidence of N3b disease for T3 (12.0% vs. 4.9%, p=0.023) and T4 tumors (33.3% vs. 17.5%, p=0.001). The 5-year RFS rate for stage III disease was marginally lower in the U group than that in the ML group (47.1% vs. 56.7%, p=0.082). The upper third location was an independent prognostic factor for both OS (hazard ratio [HR], 1.350; 95% confidence interval [CI], 1.065-1.711) and RFS (HR, 1.430; 95% CI, 1.080-1.823).

CONCLUSIONS

Upper-third gastric cancer shows extensive node metastasis compared to those located more distally in ≥T3 tumors. The upper third location is an independent prognostic factor for both OS and RFS and may have an adverse impact on RFS, particularly in patients with stage III gastric cancer.

Risk factors and oncological impact of positive resection margins in gastrectomy for cancer: are they salvaged by an additional resection?

BACKGROUND

The situation of positive resection margins (PRMs) varies notably between Western and Asian countries. In the West, PRMs are associated with advanced disease and R1, whereas in Asia, PRMs are also considered in early disease because stomach preservation was recently prioritized. Furthermore, PRMs are usually resected to obtain R0. However, the oncological impact of PRMs and additional resection remains unclear. The aim of this study is to evaluate the oncological impact of PRMs in laparoscopic gastrectomy (LG) for clinical stage (cStage) I gastric cancer.

METHODS

A total of 2121 patients who underwent LG for cStage I gastric cancer between 2007 and 2015 were enrolled. Survival outcomes were compared between patients with PRMs (group P) and those without (group N). Furthermore, prognostic factors were analyzed using multivariate analysis.

RESULTS

Twenty-seven patients (1.3%) had PRMs. Patients in group P had upper and more advanced disease, and the 5-year relapse-free survival (RFS) rate was worse in group P compared with group N (76.3% vs. 95.1%, P = 0.003). The 5-year RFS of patients with pT2 or deeper (pT2-4) disease in group P was significantly worse than that of patients in group N (66.7% vs. 89.5%, P = 0.030) although that of patients with pT1 was not. Likelihood ratio tests showed that there was a significant interaction between pT status and PRM (P = 0.005).

CONCLUSION

PRM in cStage I gastric cancer is associated with advanced upper disease. It remains an independent prognostic factor in pT2-4 disease even after an additional resection to obtain R0.

Disease-Specific Survival of AJCC 8th Stage II Gastric Cancer Patients After D2 Gastrectomy

The association between the risk factors and long-term prognosis in patients with stage II gastric cancer after radical gastrectomy has been fully revealed. The purpose of this study was to investigate the independent risk factors for treatment failure in stage II gastric cancer. Demographic, clinical, and pathological information of 247 stage II gastric cancer patients who underwent radical D2 gastrectomy in our department between January 2011 and December 2014 were collected and retrospectively analyzed. The relationship between and long-term clinical outcomes of stage II gastric cancer was analyzed using t-tests, chi-square tests, receiver operating characteristic (ROC) analysis, time-dependent ROC analysis, K–M curves, and a Cox regression model. The median follow-up of 247 stage II gastric cancer patients was 5.49 years (range: 0.12–8.62 years). The Kaplan–Meier estimated 3-year and 5-year DSS rates of the study group were 92.7% (95% CI 89.4–95.9) and 88.7% (95% CI 84.7–92.7), respectively. Higher age (>70 vs. ≤70, log-rank p = 0.0406), nerve invasion (positive vs. negative, log-rank p = 0.0133), and non-distal gastrectomy (distal partial gastrectomy vs. other surgical methods, log-rank p = 0.00235) had worse prognoses compared to controls. Univariate and multivariate analyses of disease-specific survival showed that these three factors were independent prognostic factors for patients with stage II disease. The area under time-dependent ROC curve (AUC) is 0.748 of 5-year survival and c-index is 0.696 based on the three-marker model drawn for stage II patients. Subgroup analyses showed an interaction between tumor location and nerve invasion. The age, perineural invasion, and surgical approach are independent prognostic factors for disease-specific survival after radical gastrectomy. Tumor location may be an important confounding factor for outcomes by affecting surgical methods and the hazards of nerve invasion.