A retrospective analysis based on the Spanish Lung Cancer Group (SLCG) clinical trial of high-dose epirubicin/cisplatin in patients with small-cell lung cancer (SCLC) was performed. Patients younger than 70 years vs. older than 70 years old were analyzed to evaluate the influence of age on response to treatment, toxicity, time to progression (TTP) and overall survival (OS) of the chemotherapy schedule. Three hundred and thirty eight patients <70 years and sixty-four >70 years, were analyzed. Objective responses were similar in both groups. In patients less than 70 years higher TTP (36 weeks vs. 32 weeks) and OS (47 weeks vs. 42 weeks) were seen, attributable to the improved results observed in the subgroup of patients with limited disease (LD). No significant differences were observed when toxicity profile of both groups was compared, except for a higher rate of febrile neutropenia observed in the elderly group with extensive disease (4.6% vs. 8.8%, p=0.01). In the subgroup of patients with LD, elderly patients received less total cisplatin dose (401 vs. 508 mg/m(2), p=0.01) although less treatment delays were reported (10 days vs. 15 days, p=0.05). Age was likely to be a negative prognostic factor for OS of elderly patients with LD. It also seemed to be related to a greater dose reduction, which may explain that toxic episodes and delays occurred more frequently in the younger patients receiving the full scheduled dose. However, the definitive reason to explain this could not be established due to the characteristics of our analysis.