Paclitaxel and concurrent radiotherapy in locally advanced non-small cell lung cancer: the Canadian experience

Several studies have been conducted to assess the safety and efficacy of paclitaxel plus radiation therapy in patients with non-small cell lung cancer (NSCLC) and to assess whether the radiosensitization demonstrated by paclitaxel in vivo can translate into clinical benefit. The National Cancer Institute of Canada Clinical Trials Group conducted a phase I/II trial in patients with inoperable stage IIIA or IIIB NSCLC to determine the maximum tolerated dose and efficacy of paclitaxel, given as a 3-hour infusion every 2 weeks during radical radiotherapy. The paclitaxel maximum tolerated dose using this schedule was 135 mg/m2; the recommended phase II dose was 120 mg/m2. The dose-limiting toxicity was grade 3 neutropenia, which prevented paclitaxel re-treatment. The overall response to all paclitaxel doses was 59% (n = 17); the overall response to the recommended phase II dose was 78% (n = 9). Median survival for all patients was 1.31 years; the 1-year survival rate was 64%. Lymphocytopenia was observed in all 17 patients; four patients had associated pneumonia or other febrile episodes during treatment. Grade 3 skin toxicity within the radiation field was reported in three patients receiving paclitaxel 120 mg/m2. This combination can be safely delivered to patients with NSCLC and has demonstrated activity in this setting. This combination has been used in Canada outside of clinical trials, and its use may be expanded as additional data from ongoing clinical trials further define the role of paclitaxel-based combined modality therapy in NSCLC.