Retrospective analysis of efficacy and safety of third-line chemotherapy for metastatic colorectal cancer among elderly patients receiving targeted therapy in early lines

Background/PurposeAbout one-half of metastatic colorectal cancer (MCRC) patients are ≥70 years of age. There is uncertainty regarding the benefit patients derive from advanced chemotherapy lines. In this study, we aim to evaluate the efficacy and safety of third-line chemotherapy treatments among MCRC patients.MethodsConsecutive patients 70 years or older at the time of diagnosis of metastatic disease who received third-line chemotherapy at the Tel-Aviv Sourasky Medical Center between the years 2000–2009 were collected. Data on demographics, stage of disease, treatment lines and oncological outcomes were extracted from their medical files.ResultsOnly 34 out of 63 patients (54%) available patients received third-line treatments. The (median) age of all patients, third-line patients and the remaining patients, were similar (74.5, 74 and 75.3 years, respectively, P = NS). Following third-line treatments, only 9% had a partial response, and the disease was stable in 29% of patients seen. Thirteen weeks is the median duration of third-line treatments. Only three patients had symptomatic relief. Importantly, 15 patients (44%) required dose reduction or treatment delay due to toxicity (neutropenia or thrombocytopenia). The median survival (mOS) is 9 months for patients with first-line treatment, 19 months for second-line treatment and 37 months for third-line treatment (Log Rank < 0.0001). There was a significant association between the number of lines of treatment and the mOS (P = 0.0001).ConclusionThird-line chemotherapy treatment of elderly MCRC patients was associated with a minor clinical response, a considerable number of side effects, but a longer survival rate. Third-line chemotherapy in fit elderly patients should be pursued, however, protocols must be adjusted before third-line treatment is implemented.