Background: Due to increased use of imaging, advanced stages of cancer are increasingly being diagnosed in an early, asymptomatic phase. Traditionally, chemotherapy is started immediately in these patients. However, a strategy wherein chemotherapy is withheld until symptoms occur may be beneficial for patients in terms of quality of life (QOL). A systematic review regarding optimal timing of chemotherapy including survival and QOL is lacking.
Methods: We systematically searched PubMed, EMBASE, and Cochrane for studies investigating the timing of start of chemotherapy in asymptomatic patients with advanced cancer. Overall survival (OS) was abstracted as primary, QOL, and toxicity as secondary outcomes. A meta-analysis was performed on OS. QOL was described using the global health status derived from the EORTC-QLQ-C30 questionnaire and toxicity as grade 3-4 adverse events.
Results: Overall, 919 patients from 4 randomized controlled trials and 1 retrospective study were included. The included studies investigated colorectal cancer (n = 3), ovarian cancer (n = 1), and gastric cancer (n = 1). Pooled analysis demonstrated no significant differences in OS between delayed and immediate start of chemotherapy (pooled HR: 1.05, 95% CI, 0.90-1.22, P = .52). QOL, evaluated in 3 studies, suggested a better QOL in the delayed treatment group. Toxicity, evaluated in 2 studies, did not differ significantly between groups.
Conclusion: This meta-analysis confirms the need for prospective studies on timing of start of chemotherapy in asymptomatic patients with advanced cancer. The limited evidence available suggests that delayed start of chemotherapy, once symptoms occur, as compared to immediate start in asymptomatic patients does not worsen OS while it may preserve QOL.
Keywords: advanced cancer; asymptomatic; chemotherapy; meta-analysis; timing.
© The Author(s) 2023. Published by Oxford University Press.