Observational Cohort Study Of First-Line Bevacizumab With Oxaliplatin Or Irinotecan And Fluoropyrimidines In Metastatic Colorectal Cancer: Hgcsg0802-Analysis Of Early Tumor Shrinkage (Ets).

753 Background: It was reported that early tumor shrinkage (ETS) was associated with better overall survival (OS) in patients (pts) with metastatic colorectal cancer (mCRC) receiving first line chemotherapy. We investigated association of ETS with progression-free survival (PFS) and OS in pts with mCRC treated with first-line bevacizumab (BV)-based chemotherapy (HGCSG0802). Methods: The objective of HGCSG0802 was to evaluate PFS, OS, response rate (RR), safety and so on. The key eligibility criteria were evaluable lesions, older than 20 years old, ECOG PS 0-2. This analysis evaluated the association of ETS at 8 weeks from the start of chemotherapy with pts characteristics, PFS and OS. To identify factors associated with ETS, if there were clinical variables with p u003c 0.2 in univariate analysis, we planned a multivariate analysis using the logistic regression model. To identify predictive and prognostic factors, a multivariate analysis was performed using Cox proportional hazard model with backward eliminat...