Course of minimal pleural effusions in non-small cell lung cancer

Aim: Patients with lung cancer may develop effusions at diagnosis or follow-up that can take three different forms: malignant pleural effusions (MPEs), paramalignant pleural effusions (PMPEs) and non-malignant effusions of known causes. Differentiating between MPE and PPE is crucial for the determination of appropriate patient management. This study examines the course of pleural effusions, and minimal pleural effusions in particular, that were detected at diagnosis and did not interfere with curative treatment during routine examinations following scheduled treatment.Material and Methods: This retrospective study included Non-Small Cell Lung Cancer (NSCLC) patients with minimal pleural effusions who were scheduled for curative treatment (concurrent chemoradiotherapy [CRT] and surgery) between January 1, 2014 and December 31, 2020. The changes in pleural effusions at follow-up were assessed.Results: At 3 months follow-up, there were six (6.3%) patients without follow-up and 14 (14.6%) patients who did not come for their follow-up appointments. Of the 76 patients with follow-up results, seven had increased pleural effusion quantities and 23 had decreased pleural effusion quantities, while the amount was similar in 46 patients. At 12 months follow-up, there were eight (8.3%) patients without follow-up, 13 (13.5%) patients who did not attend their follow-up appointments, and two (2.1%) patients who died. Of the 73 patients with follow-up data, 11 had increased pleural effusion quantities and 23 had decreased pleural effusion quantities, while the amount was similar in 39 patients.Discussion: Patients without distant metastasis at diagnosis may be considered for curative treatment, which provides better survival, based on a careful assessment of the clinical and radiological variables of the minimal pleural effusions in such patients at diagnosis.