Predictors of outcome in elderly patients with metastatic colorectal cancer: the final results of a prospective phase II study of bevacizumab in combination with capecitabine as first-line treatment

Anticancer Drugs. 2020 Jun;31(5):518-522. doi: 10.1097/CAD.0000000000000892.

Abstract

In 2011, we demonstrated that bevacizumab in combination with capecitabine as first-line treatment is effective in elderly patients with metastatic colorectal cancer (mCRC). We present the final results of the study with data on tumor molecular biology, sidedness and postprogression therapy. Forty patients with mCRC aged ≥70 years, initially treated with bevacizumab and capecitabine, were followed from the start of the treatment of metastatic disease to death. Tumor tissue samples were retrospectively analyzed for RAS, BRAF and microsatellite status. After a median follow-up time of 20.5 months, the median progression-free survival (PFS) and overall survival (OS) were 9.8 and 20.5 months, respectively and the objective response rate (ORR) was 65%. Twelve patients had mutation in RAS and four patients in BRAF gene, which coexisted with MSI in two cases. Patients with the right-sided tumor had apparently, but not statistically significantly lower PFS (8.6 vs. 13 months, P = 0.14) and statistically significantly lower OS (13 vs. 23.1 months, P = 0.046). Twelve patients with one or more postprogression therapy lines had significantly better ORR (12/12 = 100% vs. 14/28 = 50%, P = 0.003), median PFS (17.2 vs. 8.5 months, P < 0.001) and median OS (42 vs. 13 months, P < 0.001) than patients who received just first-line study treatment. Elderly patients with mCRC responded favorably to bevacizumab and capecitabine, especially the subgroup with the left-sided primary tumor. In the further subset of this group, characterized by RAS/BRAF wild-type and MSS tumors, the application of postprogression therapies was feasible and resulted in significant prolongation of survival.

Publication types

  • Clinical Trial, Phase II
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Bevacizumab / administration & dosage
  • Biomarkers, Tumor / genetics*
  • Capecitabine / administration & dosage
  • Colorectal Neoplasms / drug therapy*
  • Colorectal Neoplasms / genetics
  • Colorectal Neoplasms / pathology
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Mutation*
  • Prognosis
  • Prospective Studies
  • Retrospective Studies
  • Survival Rate

Substances

  • Biomarkers, Tumor
  • Bevacizumab
  • Capecitabine