Correlation of Pathological Complete Response With Tumor Volume Reduction During Neoadjuvant Chemoradiotherapy in Lung Cancer

Background/Aim: We retrospectively investigated the relationship between pathological complete response (pCR) and tumor volume (TV) reduction during neoadjuvant chemoradiation therapy (NACRT) in non-small cell lung cancer (NSCLC). Patients and Methods: We evaluated patients who received NACRT (50 Gy/25 fractions with platinum-doublet) plus surgery for NSCLC. TVs before and during NACRT (TVbefore and TVduring, respectively) were measured based on the sums of the volumes of primary tumors and clinically positive lymph nodes. Relative change in TV was computed as % (TVduring - TVbefore)/TVbefore. Results: In total, 31 patients were analyzed. The median of the relative change in TV was - 49% and ranged from -83 to -10%. Postoperatively, pCR was achieved in 11 patients (35%). In multivariate analysis, the relative change in TV was found to be an independent predictor of pCR (p=0.003). Conclusion: TV reduction during NACRT appears to be associated with pCR in NSCLC.