National Trends in Utilization of Endoscopic Ultrasound for Gastric Cancer: a SEER-Medicare Study

Endoscopic advances in the management of gastric cancer and premalignant gastric conditions

Gastric cancer is the fifth most common cancer and in 2018, it was the third most common cause of cancer-related deaths worldwide. Endoscopic advances continue to be made for the diagnosis and management of both early gastric cancer and premalignant gastric conditions. In this review, we discuss the epidemiology and risk factors of gastric cancer and emphasize the differences in early vs late-stage gastric cancer outcomes. We then discuss endoscopic advances in the diagnosis of early gastric cancer and premalignant gastric lesions. This includes the implementation of different imaging modalities such as narrow-band imaging, chromoendoscopy, confocal laser endomicroscopy, and other experimental techniques. We also discuss the use of endoscopic ultrasound in the diagnosis and staging of early gastric cancer. We then discuss the endoscopic advances made in the treatment of these conditions, including endoscopic mucosal resection, endoscopic submucosal dissection, and hybrid techniques such as laparoscopic endoscopic cooperative surgery. Finally, we comment on the current suggested recommendations for surveillance of both gastric cancer and its premalignant conditions.

Validation of the 8th AJCC staging system for gastric cancer in a population-based setting

BACKGROUND

The aim of this analysis is to validate the prognostic value of the 8^th edition of the American Joint Committee on Cancer (AJCC) staging system for gastric cancer.

METHODS

Through SEER*Stat program, Surveillance, epidemiology and end results database (2010-2013) was accessed and 8th AJCC stages were reconstructed. Cancer-specific survival analyses according to both 7th and 8th editions were conducted through Kaplan-Meier analysis/log-rank testing and multivariate analysis was conducted through a Cox model.

RESULTS

Among pathologically-staged patients, P values for pairwise comparisons among different 8th AJCC stages were significant (<0.05) for all comparisons except for stage IIIC vs. IV; while P values for pairwise comparisons among different 7th AJCC stages were significant (<0.05) for all comparisons except for stage IIIA vs. IIIB and stage IIIC vs. IV. Among clinically-staged patients and according to either the clinical 8th AJCC or the 7th AJCC, significant overlap in outcomes existed between different stages. Among pathologically-staged patients, c-statistic for the pathological 8th system was: 0.762; while for the 7th system, it was: 0.763. Among clinically-staged patients, c-statistic for the clinical 8th system was: 0.634; while for the 7th system, it was: 0.637.

CONCLUSION

Compared to the 7th system, the 8th system does not bring about significant prognostic improvement (for either clinically- or pathologically-staged patients).

Role of endoscopic ultrasonography in TNM staging of gastric cancer

Gastric cancer is a common malignancy that has a poor prognosis and high mortality. Cancer staging is the optimal method for evaluating prognosis. Endoscopic ultrasonography (EUS) has been considered the first-choice imaging modality for regional staging of gastric cancer because different structural layers of the gastric wall show remarkable differences in their echogenic appearance. However, the results of recent studies about the accuracy of EUS for staging of gastric cancer are contradictory. The aim of this article is to review the role of EUS in preoperative TNM staging of gastric cancer.