Background The standard of care for advanced NSCLC is platinum-based chemotherapy but the optimal dose of cisplatin and comparison with carboplatin is uncertain. With median survival at 8–12 months, the impact of such treatment choices on patients' quality of life (QoL) is important. The BTOG2 trial is a large phase III randomised trial comparing three treatment arms: gemcitabine (1250 mg/m2 day 1 and day 8) with either cisplatin 80 mg/m2 (GC80), cisplatin 50 mg/m2 (GC50) or carboplatin AUC6 (GCb6). The trial was innovative in aiming to collect QoL data on all trial patients and is the largest study to date addressing this issue in NSCLC.
Methods QoL was measured at each cycle of chemotherapy and each follow-up visit using standard, validated questionnaires: EORTC QLQ-C30, LC13 and EQ-5D.
Results More than 8000 questionnaires were returned from 1363 randomised patients with compliance around 90% during the treatment period. At pre-randomisation, the mean global heath status score and EQ-5D utility score were 62% and 0.66. On initiation of treatment, patients in all three treatment arms had improved pain, cough, haemoptysis, insomnia, appetite loss and emotional functioning with associated improvements in global measures of QoL but these benefits generally fell away after completion of chemotherapy (12+ weeks). GC50 performed better in terms of the functioning scores and in terms of fatigue, nausea and vomiting while GCb6 performed worst for dyspnoea. All treatments had a deleterious effect on peripheral neuropathy with the post-treatment toxicity momentum markedly worse for GC80. Mean quality-adjusted life months were 6.1 on GC80, 5.6 on GC50 and 6.1 on GCb6.
Conclusion Although higher doses of cisplatin (80 mg/m2) are thought detrimental to QoL compared to 50 mg/m2 we found minimal differences but a noteworthy problem in delayed neuropathy. Also, the belief that carboplatin produces superior QoL compared to cisplatin at either dose is not obvious. Importantly carboplatin treatment may not palliate dysponea as well as cisplatin. Adjusting for QoL does not change the conclusions from the primary survival analysis.