Comparing irinotecan/cisplatin with etoposide/cisplatin in patients with ED-SCLC: A meta-analysis of efficacy and toxicity

ObjectiveIrinotecan in combination with cisplatin for extensive-stage disease small-cell lung cancer (ED-SCLC) patients has gained wide interest. Varying results for this treatment underpin the need for a synthesis of evidence.MethodsWe conducted a literature-based meta-analysis to quantify the magnitude of the benefit comparing irinotecan in combination with cisplatin (IP) with etoposide in combination with cisplatin (EP) in ED-SCLC patients. The primary outcome was overall survival (OS) and progression-free survival (PFS); secondary outcomes included overall response rate, 1- and 2-year survival rates, disease control rate and toxicity.ResultsFour trials including 1,541 patients were identified in the analysis. No positive results (P<0.05) were seen: OS (HR=0.85, CI95%=0.71–1.01; P=0.08) with high heterogeneity (Chi2=7.76, df=3 [P=0.05]; I2=61%), PFS (HR=0.91, CI95%=0.74–1.28; P=0.36) with high heterogeneity (Chi2=11.96, df=3 [P=0.008]; I2=75%), overall response rate (OR=1.16; CI95%=0.79–1.70; P=0.45), disease control rate (OR=1.01; CI95%=0.74–1.38; P=0.95), 1-year survival rate (OR = 1.30; CI95%=0.98–1.72; P=0.07) and 2-year survival rate (OR=1.97; CI95%=0.95–4.09; P=0.07). Fewer patients who received IP suffered severe hematologic toxicities (grade≥3), such as neutropenia, thrombocytopenia and leucopenia. However, severe non-hematologic toxicities (grade≥3), such as diarrhea, nausea, vomiting, fatigue, anorexia, and dehydration, were more common among patients who received IP.ConclusionIP does not lengthen the overall survival or progression-free survival compared with EP in patients with ED-SCLC. Fewer patients receiving IP had grade≥3 hematological toxicities of neutropenia, leucopenia and thrombocytopenia, but more had grade≥3 diarrhea, nausea, vomiting, fatigue, anorexia and dehydration.