Randomized study of concurrent carboplatin, paclitaxel, and radiotherapy with or without prior induction chemotherapy in patients with locally advanced non-small cell lung cancer.

Background: Multiple concepts of combined modality therapy for locally advanced inoperable non-small cell lung cancer have been investigated. These include induction chemotherapy, concomitant chemo-radiotherapy, and radiation only. To date, combined modality therapy specially the use of concomitant chemo-radiotherapy has led to promising results and was shown to be superior to radiotherapy alone in phase II studies. However the optimum chemo-therapeutic regimen to be used as well as the benefit of induction chemotherapy before concomitant chemo-radiotherapy are yet to be determined. Based on these observations, we investigated the use of paclitaxel and carboplatin concomitantly with radiotherapy and the benefit of prior two cycles induction chemotherapy.

Materials And Methods: In this trial 60 patients with locally advanced inoperable non small cell lung cancer, good performance status and minimal weight loss have been randomized into 3 groups each of 20 patients. Group A received induction 2 cycles paclitaxel (175 mg/m2) and carboplatin (AUC 6) on day 1 and 28th followed by concomitant paclitaxel (45 mg/m2) and carboplatin (AUC 2) weekly with radiotherapy. Group B received concomitant carboplatin, paclitaxel (same doses as in group A) and radiotherapy with no prior induction chemotherapy. Group C received only radiotherapy to a total dose of 60 Gy in conventional fractionation.

Results: A total of 60 patients were enrolled in this study between 1998 and 2000. Pretreatment characteristics, including age, gender, performance status, histological features and stage were comparable in each group. The incidence of oesophagitis was significantly higher in group A and B than in group C (p=0.023). Hematological toxicities was also significantly higher in group A & B than in group C (p=0.003). The response rate was significantly higher in group A and B than in group C (75%, 79%, and 40% respectively) (p=0.020). The time to in-field progression was significantly higher in group B as compared to group A (48% vs. 32% failure in 2 years respectively) (p=0.000). The median 2 year survival was significantly higher in group A and B than in group C (p=0.039) but no statistical difference was seen between group A and B.

Conclusion: Combined chemo-radiotherapy resulted in better response and survival as compared to conventional radiotherapy in the treatment of locally advanced nonsmall cell lung cancer. Early initiation of radiation with concomitant chemotherapy resulted in prolonged time to infield progression. On the other hand, two cycles of induction chemotherapy did not show any significant difference regarding the response or survival. Weekly paclitaxel and carboplatin plus radiotherapy is a well tolerated regimen for outpatients with encouraging results.