Which variables should be considered in patients with stage II and III non-small cell lung cancer after neoadjuvant therapy?

This study was designed to elucidate the predictive usefulness of the response evaluation criteria in solid tumors (RECIST), a volume response (VR; a > 50% reduction in the tumor volume) and the post-neoadjuvant therapy maximum standardized uptake value (post-SUVmax) in patients with non-small cell lung cancer (NSCLC) after neoadjuvant therapy. Between December 2006 and June 2012, 33 patients with clinical stage II and III NSCLC who underwent pulmonary resection following neoadjuvant therapy were enrolled. The relationships between the variables and a pathological complete response (pCR), the disease-free survival (DFS) and the overall survival (OS) were analyzed. As neoadjuvant therapy, 24 patients received chemoradiotherapy, five patients received chemotherapy and four patients were given radiation therapy. Based on the RECIST, 12 tumors were classified as having a partial response and 21 tumors were classified as stable disease. Twenty-one tumors showed a VR and 12 did not. Twenty-five tumors had a post-SUVmax ≤7.5 and eight had a post-SUVmax >7.5. Eight tumors had a pCR. In the multivariate Cox regression analysis, both a non-VR and a post-SUVmax >7.5 were significant variables predicting the DFS (p = 0.0422 and 0.0127, respectively), but either was not for OS. The post-SUVmax was also a significant variable for the pCR rate (p = 0.0067). The post-treatment SUVmax can be a valid alternative variable that can be used to predict the effect of neoadjuvant therapy and the survival of patients with stage II and III NSCLC.