Paclitaxel as a radiation sensitizer in non-small cell lung cancer

The new anticancer agent paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) has demonstrated in vitro radiation-sensitizing effects. In this phase I study, paclitaxel in escalating doses was administered weekly with concurrent radiation therapy to patients with regionally advanced non-small cell lung cancer (NSCLC). The goal was to determine the maximum tolerated dose of paclitaxel in this combination, to identify toxicities, and to evaluate response. Twenty-seven patients with NSCLC were enrolled into a phase I trial of concurrent paclitaxel and radiation therapy administered as a 3-hour infusion each week for 6 weeks. The paclitaxel doses ranged from 10 to 70 mg/m2/wk. Radiation therapy was delivered with weekly paclitaxel as 40 Gy in 20 fractions to the original volume with a boost of 20 Gy in 10 fractions to the primary tumor. Esophagitis was the dose-limiting toxicity at a maximum tolerated dose of 60 mg/m2/wk. The combination of concurrent radiation therapy and weekly outpatient paclitaxel can be safely delivered to patients with NSCLC at a dose of 60 mg/m2. Esophagitis appeared to be the dose-limiting toxicity. A phase II study of concurrent paclitaxel and radiation therapy is under way.