Optimal treatment change criteria for advanced gastric cancer with non-measurable peritoneal metastasis: symptom/tumor marker-based versus CT-based.

Background: For advanced gastric cancer (AGC) with peritoneal metastasis, decision-making regarding treatment change is often challenging because of the absence of measurable lesions. We attempted to clarify which criterion for treatment change contributes more to longer survival.

Patients And Methods: We retrospectively reviewed 50 patients with non-measurable peritoneal metastasis in whom first-line chemotherapy for AGC was changed based on aggravated clinical symptoms or tumor markers (TMs), or radiologically-confirmed disease progression. Prognostic factors for overall survival (OS) were investigated.

Results: Patients whose treatment was changed based on symptoms/TMs had significantly longer OS than patients with computed tomographic-based treatment change (p=0.04). On multivariate analysis, treatment change based on symptoms/TMs was identified as an independent prognostic factor for favorable OS (hazard ratio=0.321, 95% confidence interval=0.154-0.668, p=0.002).

Conclusion: The present study suggests that aggravated clinical symptoms/elevated TMs could be a sensitive predictor for disease progression in patients with AGC with non-measurable peritoneal metastasis.