Accelerated-interrupted radiation therapy given concurrently with chemotherapy for locally advanced non-small cell lung cancer.

PURPOSE: To evaluate the efficacy of multidrug chemotherapy combined with accelerated radiation therapy in the treatment of localized but unresectable non-small cell lung cancer.

PATIENTS AND METHODS: Between September 1990 and February 1993, 35 patients with Stage III (15 IIIA & 20 IIIB) non-small cell lung cancer were entered on a protocol using combined accelerated radiation therapy and chemotherapy. Radiation therapy consisted of 55.6 Gy in 30 fractions (1.8 Gy bid for 5 consecutive days given in 3 weeks [total of 15 days], every other week). Chemotherapy consisted of cisplatin (10 mg/m2), vinblastine (4 mg/m2), 6-thioguanine (40 mg bid), and 5-fluorouracil (400 mg/m2 as continuous infusion) given concomitantly with radiation therapy. Approximately 3 weeks following completion of radiation therapy, two cycles of consolidation chemotherapy were given, consisting of two doses of cisplatin (120 mg/m2) 4 weeks apart and six doses of vinblastine (4 mg/m2) given on two consecutive days every other week for 3 weeks.

RESULTS: Six patients were still alive at last follow-up; for them the median follow-up time is 47 months (range, 39-55.8). The median survival time is 17.5 months. The 1-, 2-, 3- and 4.5-year survival rates are 69%, 37%, 20% and 17%, respectively. Overall response rate is 63%, with 51.5% partial response and 11.5% complete response rates. Esophagitis occurred as follows: Grade 4 = 0, Grade 3 = 1, Grade 2 = 6, and Grade 1 = 13. No patient developed Grade 3 or 4 acute respiratory toxicity. Significant hematologic toxicity occurred as follows: 37% Grade 3 and 31% Grade 4 leukopenia. Radiation pneumonitis occurred in two patients.

DISCUSSION: The regimen tested in this protocol appears to be very well tolerated with minimal pulmonary or esophageal toxicity. This, coupled with the shortened course of radiation therapy and the ability to deliver the combined radiation and chemotherapy portion of the treatment on an outpatient basis most of the time, has made multi-modality treatment for this malignancy much easier and more convenient for patients. In addition, the favorable survival in this group of patients with locally advanced disease is very encouraging and warrants further study.