Survival outcomes in patients with stages I-III gastric adenocarcinoma treated with surgery alone versus surgery plus adjuvant chemotherapy: A systematic review.

Background: Gastric adenocarcinoma, the malignant proliferation of glandular cells in stomach epithelium, is a type of gastric cancer with a statistical disease burden of the fifth most common cancer globally and the 17^th most common malignancy in the United Kingdom. Prognosis varies with stage (I-IV), with stages I-III showing promising 5-year survival rates up to 71.8%, warranting timely diagnosis and treatment. Surgery is the gold-standard treatment; however, due to complex tumor pathophysiology, there is growing interest in the use of multimodal therapies. Specifically, the combination of surgery and adjuvant chemotherapy has become a key focus of the treatment for stages I-III gastric adenocarcinoma.

Objective: The study reviewed patients with stages I-III (non-advanced) gastric adenocarcinoma to assess whether adjuvant chemotherapy combined with surgery provides better disease-free/disease-specific/cause-specific survival, overall survival, and reduced recurrence rates/improved recurrence-free survival, compared to surgery alone. Analyzed were 17 English-language, full-text, levels I-III peer-reviewed studies from MEDLINE and Embase from the past 10 years were analyzed. No age/sex/ethnicity/country restrictions were applied, and the dimension of interest was limited to stages I-III gastric adenocarcinoma patients who underwent tumor resection through surgery and received chemotherapy as the only adjuvant therapy. Seven (41.2%) studies have more than one statistically significant outcome measure supporting the benefit of adjuvant chemotherapy in combination with surgery over surgery alone. Ten (58.8%) studies showed no statistically significant benefit of adjuvant chemotherapy.

Conclusion: The findings contrasted with previous large-scale meta-analyses, which were limited by sample size and biases in individual studies reviewed. Continued research, incorporating advances in surgical techniques and new chemotherapeutic combinations, is necessary to ascertain best-tailored treatments for gastric adenocarcinoma.