P2-163: Concurrent Chemoradiation for Stage III Non-Small Cell Lung Cancer (NSCLC): A Single Institution Canadian Experience

Abstract

Combined modality therapy remains the best chance of cure in the setting of locally advanced NSCLC. The optimal combination of concurrent chemotherapy and radiation (CRT) continues to evolve. In this study we report our single institution experience with tri-modality therapy in patients with Stage III NSCLC. 55 patients with Stage III NSCLC and ECOG 0-1 were prospectively studied between September 1995 and March 2004 at CancerCare Manitoba, Winnipeg, Canada. From 1995 through 1997, the standard regimen (PE) consisted of Cisplatin (25 mg/m2) & Etoposide (100 mg/m2) for 3 days every 3 weeks for 2 cycles combined with either radical intent (5000 cGy in 20 fractions) or palliative intent (3000-3500 cGy in 10 fractions) concurrent radiation. In 1998, the standard regimen was switched to TC using Carboplatin (AUC 3) & Paclitaxel (45mg/m2) once weekly for 4-6 weeks combined with 5000 cGy in 20 fractions. After a treatment related death in 1999, the Carboplatin dose was reduced (AUC 2) and radiation was revised to either 4500 cGy in 25 fractions for Stage IIIa or 6000 cGy in 30 fractions for Stage IIIb disease. All patients were assessed for clinical response, toxicity, surgical resection, pathologic response, and survival. Median age was 62, Stage IIIa 59%, and Adenocarcinoma 43%. Eighty-eight percent of patients received their prescribed dose of PE and 90% received at least four cycles of prescribed TC chemotherapy. Radical radiation therapy was the intended therapy in 95% of cases however only 75% of patients received at least 5000 cGy of radiation. Clinical response to therapy is shown in the table below. Tabled 1RegimenNComplete ResponsePartial ResponseStable DiseaseProgressive DiseaseCisplatin & Etoposide (PE)260 (0%)17 (59%)8 (28%)4 (14%)Carboplatin & Paclitaxel (TC)292 (8%)8 (31%)8 (31%)8 (31%)Grade 3 toxicity occurred in 2 patients on PE and 10 on TC. One patient receiving TC died of treatment related toxicity. Ten patients in Open table in a new tab Grade 3 toxicity occurred in 2 patients on PE and 10 on TC. One patient receiving TC died of treatment related toxicity. Ten patients in Grade 3 toxicity occurred in 2 patients on PE and 10 on TC. One patient receiving TC died of treatment related toxicity. Ten patients in each chemotherapy group went on to surgical resection with partial pathologic response seen in 50% PE and 80% TC. Median survival was 2.05 years for this population with no significant survival difference between treatment groups (PE 2.25 vs. TC 1.98 years, p = 0.39). Dose of radiation (≥5000 cGy vs. <5000 cGy) did not significantly impact survival. Patients who proceeded to surgical resection survived a median of 3.33 years compared to 1.62 years for un-resected patients (p = 0.0006). In our experience, both combinations of chemotherapy combined with radiation were equally effective in terms of overall survival in Stage III NSCLC. TC based CRT appears to have better clinical and pathologic response compared to PE at the expense of a slight increase in treatment related toxicity. The few patients who proceeded to surgery post CRT had significantly improved survival.