Review of Maintenance Therapies for Patients With Metastatic Colorectal Cancer
Posted: Thursday, January 30, 2020
According to a systematic review and network meta-analysis in JAMA Oncology, there appears to be no benefit to continuing full induction therapy until disease progression for patients with metastatic colorectal cancer without a period of observation or maintenance treatment. A maintenance treatment strategy including fluoropyrimidine—with or without bevacizumab—is recommended, according to Mohamad Bassam Sonbol, MD, of the Mayo Clinic, Phoenix, and colleagues.
“However, given the lack of a clear [overall survival] benefit, shared decision-making should include observation as an acceptable alternative,” the authors noted.
The investigators analyzed 12 relevant randomized clinical trials including 5,540 patients with metastatic colorectal cancer. The trials in which patients started an initial therapy of cytotoxic chemotherapy and then switched to observation were included: maintenance with bevacizumab, fluoropyrimidine, or both, or continued induction regimen until disease progression. The investigators ranked the agents using surface under the cumulative ranking (SUCRA) probabilities.
The network meta-analysis showed no benefit of continuing full cytotoxic chemotherapy until disease progression compared with observation in terms of progression-free and overall survival. Maintenance therapy demonstrated a progression-free survival benefit, but not an overall survival benefit. All maintenance strategies showed significant improvement in progression-free survival compared with observation.
For SUCRA probabilities, maintenance treatments resulted in the highest likelihood of improved progression-free survival (99.8% with fluoropyrimidine plus bevacizumab, 67.1% with fluoropyrimidine, and 36.5% with bevacizumab) and overall survival (81.3% with fluoropyrimidine, 73.2% with fluoropyrimidine and bevacizumab, and 32.6% with bevacizumab).
“We confirm that maintenance therapy and even a cessation of treatment are acceptable options vs continuing the full regimen,” the authors commented. “A clear advantage for de-escalating treatment after achieving a maximum response (typically 3–4 months) with induction therapy includes minimizing toxic effects, maximizing quality of life, and likely improving cost.”
Disclosure: For full disclosures of the study authors, visit jamanetwork.com.