Clinical outcomes of targeted therapies in elderly patients aged ≥ 80 years with metastatic colorectal cancer

BACKGROUND: The 5-fluorouracil-based chemotherapy combined with oxaliplatin or irinotecan is usually used in colorectal cancer (CRC). The addition of a targeted agent (TA) to this combination chemotherapy is currently the standard treatment for metastatic CRC. However, the efficacy and safety of combination chemotherapy for metastatic CRC in patients aged above 80 years has yet to be established. AIM: To assess the clinical outcomes and feasibility of combination chemotherapy using a TA in extremely elderly patients with CRC. METHODS: Eligibility criteria were: (1) Age above 80 years; (2) Metastatic colorectal cancer; (3) Palliative chemotherapy naïve; (4) Eastern Cooperative Oncology Group performance status 0-1; and (5) Adequate organ function. Patients received at least one dose of combination chemotherapy with or without TA. Response was evaluated every 8 wk. RESULTS: Of 30 patients, the median age of 15 patients treated with TA was 83.0 years and that of those without TA was 81.3 years. The median progression-free survival (PFS) and overall survival (OS) in patients treated with TA were 7.4 mo and 15.4 mo, respectively, compared with 4.4 mo and 15.6 mo, respectively, in patients treated without TA. There was no significant difference in PFS (P: 0.193) and OS (P: 0.748) between patients treated with and without TA. Common grade 3/4 hematologic toxicities were anemia (16.7%) and neutropenia (10.0%). After disease progression, the median OS of patients who were treated with and without salvage chemotherapy were 23.5 mo and 7.0 mo, respectively, suggesting significant difference in OS (P = 0.001). CONCLUSION: Combination chemotherapy with TA for metastatic CRC may be considered feasible in patients aged above 80 years, when with careful caution. Salvage chemotherapy can help improve OS in some selected of these elderly patients.