Patterns of Use and Tolerance of Anti–Epidermal Growth Factor Receptor Antibodies in Older Adults With Metastatic Colorectal Cancer

Abstract

Introduction Limited data are available regarding the tolerance of anti-epidermal growth factor receptor (EGFR) antibodies among elderly metastatic colorectal cancer (mCRC) patients. We retrospectively reviewed our experience of treating elderly mCRC patients with these agents between 2004 and 2011. Methods mCRC patients ≥65 years old treated with anti-EGFR agents were included in this analysis. We recorded demographic and disease characteristics, treatment regimen and duration, KRAS status, and overall survival. Toxicity evaluation included common hematologic and non-hematologic toxicities seen with these agents. Results 117 patients were included with median age at treatment initiation of 73 years (65–86), 59% male gender, 82% colon primary, and 51% with metastatic disease at presentation. Median time on anti-EGFR treatment was 2.4 months. Older age at treatment initiation was associated with use of anti-EGFR antibody as monotherapy versus combination (p=0.0009). Worse performance status at treatment initiation was associated with a shorter overall survival (p=0.013) and shorter treatment duration (p=0.01). The incidence of hematologic/non-hematologic grade 3 or higher toxicity was 36% and 15% respectively. No association was found between age and presence of ≥ grade 3 toxicities. Longer treatment duration and better performance status at treatment initiation were the only factors associated with higher incidence of grade 3 toxicity. Conclusions Our data demonstrate that anti-EGFR antibodies can be used among older mCRC patients, with toxicity profiles similar to those reported in large phase III studies of younger patients. Advanced age was associated with receipt of anti-EGFR agents as monotherapy, but did not impact treatment outcomes in this population.

Comparative Effectiveness and Safety of Monoclonal Antibodies (Bevacizumab, Cetuximab, and Panitumumab) in Combination with Chemotherapy for Metastatic Colorectal Cancer: A Systematic Review and Meta-Analysis

“…Eight studies declared COI, nine studies declared having no COI, and three studies did not provide this information. With respect to funding, seven studies did not mention the sources of funding [71, 72, 76, 80–83], seven declared having been funded by the pharmaceutical industry [42, 73, 75, 78, 84–86], and the other studies were funded through other sources.…”

“…Two arms were built, i.e., BEVA versus no BEVA, since it was not possible to compare CETUX versus PANIT since there were concerns with the key measurements used. In addition to finding only two studies [12, 75] with this comparison, the authors used the median as a measure of central tendency. This is different from the other arms, where means were used for comparative purposes, making it difficult to include this arm in the analysis.…”