Efficacy evaluation of neoadjuvant immunotherapy plus chemotherapy for non-small-cell lung cancer: comparison of PET/CT with postoperative pathology.

ABSTRACT

OBJECTIVES: To assess the value of positron emission tomography/computed tomography (PET/CT) in the efficacy evaluation of patients undergoing neoadjuvant immunotherapy plus chemotherapy, and to analyze its correlation with postoperative pathology. METHODS: The PET/CT metabolic parameters and CT size were retrospectively analyzed before and after neoadjuvant immunotherapy plus chemotherapy in 67 patients with resectable stage II/IIIA non-small-cell lung cancer (NSCLC). CT assessment based on immune response evaluation criteria in solid tumor criteria ((i)RECIST) was compared with PET/CT assessment based on the response criteria in solid tumors (PERCIST). The correlations between PET/CT metabolic parameters and postoperative pathology were analyzed. The value of PET/CT in the efficacy evaluation was assessed. RESULTS: The PET/CT assessment showed high consistency with postoperative pathological evaluation, yet the CT assessment showed low consistency with postoperative pathological evaluation. The (i)RECIST and PERCIST criteria showed statistically significant differences (p < 0.001). The postoperative pathological response was negatively associated with ΔSUVmax (%) (r = - 0.812, p < 0.001), ΔSUVmean (%) (r = - 0.805, p < 0.001), and ΔSUVpeak (%) (r = - 0.800, p < 0.001). The cut-off values of 75.8 for ΔSUVmax (%), 67.8 for ΔSUVmean (%), and 74.6 for ΔSUVpeak (%) had the highest sensitivity and specificity. CONCLUSION: The PERCIST criteria are more sensitive and accurate than (i)RECIST criteria to identify more responders when evaluating the response of neoadjuvant immunotherapy plus chemotherapy for NSCLC. PET/CT shows high accuracy in predicting postoperative pathological response. Our study shows the important role PET/CT plays in the efficacy evaluation of NSCLC patients undergoing neoadjuvant immunotherapy plus chemotherapy, as well as in predicting the prognosis and guiding postoperative treatment. CLINICAL RELEVANCE STATEMENT Neoadjuvant immunotherapy plus chemotherapy is highly effective in the treatment of non-small-cell lung cancer. And PET/CT played an important role in the efficacy evaluation following neoadjuvant immunotherapy plus chemotherapy for non-small-cell lung cancer. KEY POINTS • Neoadjuvant immunotherapy plus chemotherapy is highly effective in the treatment of NSCLC. • The PERCIST criteria are more sensitive and accurate than (i)RECIST criteria to identify more responders when evaluating the response of neoadjuvant immunotherapy plus chemotherapy for NSCLC. • PET/CT played an important role in the efficacy evaluation; ΔSUVmax (%), ΔSUVmean (%), and ΔSUVpeak (%) following neoadjuvant immunotherapy plus chemotherapy for NSCLC had high consistency and strong correlations with postoperative pathology.