Survival outcomes with curative intent hyperthermic intraperitoneal chemotherapy (HIPEC) for gastric cancer with peritoneal metastasis.

Abstract

e16070 Background: The prognosis of gastric cancer with peritoneal metastasis (GC-PM) remains dismal. Despite the many studies evaluating hyperthermic intraperitoneal chemotherapy and cytoreductive surgery (HIPEC-CRS) for GC-PM in various treatment settings, its curative role in combination with systemic chemotherapy remains unclear. Methods: To determine the survival benefit of CRS-HIPEC in patients with GC-PM, we conducted a systematic review and meta-analysis in accordance with the PRISMA guidelines on primary studies from January 1, 2010 to December 31, 2023. Inclusion criteria were studies involving adults with GC and histologically proven PM who received curative intent gastrectomy, D2 lymphadenectomy, and systemic chemotherapy. Exclusion criteria were studies involving patients with GC without PM involvement and HIPEC utilized strictly for prophylactic purposes. The primary endpoint was overall survival (OS), with a focus on 1-year, 2-year, and 3-year survival outcomes. We performed a random effects meta-analysis of risk ratios using RevMan and assessed heterogeneity using I2. Results: Of 452 studies identified, we included 5 studies and a total of 524 patients with survival outcome of CRS-HIPEC and standard chemotherapy were compared. We observed significantly better OS for patients who received CRS+HIPEC compared to those who received systemic chemotherapy without CRS-HIPEC (odds ratio (OR) 0.50, 95% CI [0.39-0.65], I2= 3%, P < 0.00001). Further analysis demonstrated improved 1-year OS (OR 0.53, 95% CI [0.30-0.93], I2= 45%, p = 0.03), 2-year OS (OR 0.53, 95% CI [0.35-0.81], I2= 0%, p = 0.003), and 3-year OS (0.35, 95% CI [0.14-0.84], I2= 21%, p = 0.02). Low heterogeneity (3%) amongst all the groups suggests that variations within the subgroups did not impact the homogeneity of the dataset. Conclusions: Overall, use of CRS and HIPEC in addition to systemic chemotherapy resulted in statistically significant improvement in OS up to year 3 compared to standard palliative chemotherapy alone in patients with GC-PM. Further studies are warranted to evaluate HIPEC in the curative attempt setting, specifically in combination with emerging targeted therapies.