Can the complete pathomorphological response be predicted based on PET/CT data in patients with resectable non-small cell lung cancer after neoadjuvant chemotherapy?

Introduction. Predicting complete pathological response (pCR) after neoadjuvant chemo-immunotherapy (CIT) in resectable non-small cell lung cancer (NSCLC) is clinically important, but the diagnostic accuracy of positron emission tomography combined with computed tomography (PET/CT) for this purpose remains uncertain. Aim. To evaluate whether PET/CT can reliably predict pCR in patients with resectable NSCLC following neoadjuvant CIT . Mat erials and methods. 40 patients with resectable NSCLC stage II–IIIB were treated with neoadjuvant CIT. All patients were recruited for radical surgery for potentially resectable tumors, assessed after neoadjuvant therapy according to RECIST 1.1, PERCIST criteria. The resected tumor samples were morphologically evaluated to determine the response to neoadjuvant therapy. Resul ts. The best response, evaluated by the dynamics of the tumor process according to RECIST 1.1 and PERCIST criteria, in the form of complete tumor regression was achieved in 3 patients (7.5%). A partial response was achieved in 27 patients (67.5%). Stabilization of the tumor process occurred in 10 patients (25%). Thus, an objective response was achieved in 30 patients (75%) and a pCR in the examination of postoperative material was registered in 50% of cases. The obtained data on the complete clinical response of the tumor to treatment based on PET/CT results and the frequency of achieving a pCR coincided in only 10% of cases, indicating a low accuracy of PET/CT in predicting the pCR to treatment. C onclusions. This study showed that the use of whole-body PET/CT to predict pCR in patients with resectable lung cancer after neoadjuvant CIT appears to be impractical.