Predictive factors related to pleural dissemination in non-small cell lung cancer

BACKGROUND: The prognosis of non-small-cell lung cancer (NSCLC) patients with pleural dissemination is poor, and pleural dissemination is generally considered a contraindication for radical surgery. However, if pleural dissemination is missed intraoperatively, patients with false-negative stage IV NSCLC cannot receive appropriate chemotherapy, and their prognosis might worsen. METHODS: In the present study, we enrolled 144 patients who received surgery for NSCLC between January 2008 and December 2019 with available data on the maximum standardized uptake value (SUV(max)) on positron emission tomography (PET) with lesions adjacent to the visceral pleura and without lesions invading the chest wall. RESULTS: Seven patients who had pleural dissemination were compared with 137 patients who had not pleural dissemination. The relationships between pleural dissemination and the clinicopathological variables were analyzed, and significant differences in the histopathological type (P=0.03), and differentiation (P<0.01) were noted. It was suggested that squamous cell carcinoma tended not to show dissemination to the pleural cavity. The logistic regression analyses of the predictive factors related to pleural dissemination in non-squamous cell carcinoma patients were analyzed, and the age (P=0.01) and differentiation (P<0.01) were identified as significant predictive factors related to pleural dissemination. CONCLUSIONS: Cases with non-squamous cell carcinoma, a young age, and poor differentiation of undifferentiated grade of histological differentiation are factors associated with early pleural cavity dissemination.