Background: We seek to investigate whether carboplatin-based induction chemotherapy before modern day concurrent chemoradiotherapy (CCRT) improves survival in patients with bulky, locally advanced nonsmall cell lung cancer (NSCLC).
Materials and methods: This analysis included 105 patients with Stage II and III NSCLC treated with definitive CCRT from 2003 to 2013. All patients underwent definitive treatment with weekly platinum-based doublet chemotherapy delivered concurrently with 60-66 Gy of thoracic radiotherapy. Thirty patients who received induction chemotherapy before CCRT had T4 disease, N3 disease, or gross tumor volume (GTV) of >150 cm 3. These patients were compared to those with unresectable disease who received CCRT alone without induction chemotherapy. Statistical analysis included univariate and multivariate methods.
Results: Mean follow-up time was 15.6 months. Patients treated with carboplatin based induction chemotherapy demonstrated prolonged overall survival (28.2 vs. 14.2 months, P = 0.04), progression free survival (12.6 vs. 9.0 months, P = 0.02), and distant metastasis free survival (15.8 vs. 10.1months, P = 0.05) compared to those who received CCRT alone without induction chemotherapy. Univariate analysis revealed older age, larger GTV, and squamous pathology as negative prognostic factors. When controlling for these factors, Cox regression analysis indicated a trend toward significantly improved overall survival in the induction cohort (P = 0.10).
Conclusion: In patients with large tumors or bulky nodal NSCLC, carboplatin-based induction chemotherapy may be an important addition to definitive CCRT in the modern era. Our findings strongly support further investigation induction chemotherapy in this population.