Noninvasive Diagnostic Methods Are Useful in Malignant Pleural Effusions

Dear Editor, I read with interest the case report titled "Chronic Lymphocytic Leukemia Hospitalized Due to Pleural Effusion - Case Report" written by Bahar Ağaoğlu Şanlı in the Acta Medica Ruha journal, page 1.3 (2023): 468-473. As a writer interested in pleural effusions in thoracic surgery, the case caught my attention. Pleural effusions are an area that requires research because they are a common clinical condition with multiple pathophysiologies (1). In the case report, it is seen that the author performed diagnostic methods related to pleural effusion management, but preferred to perform a blind biopsy because the patient's general condition was not suitable for surgical biopsy. In the study, no malignant cells were observed in the pleural fluid and no malignant cells were detected as a result of blind biopsy. I believe that the author's contribution to the dark side of pleural effusions with this case resulting in mortality will bring a remarkable perspective to the literature and I congratulate the author. Currently, aspiration and cytological evaluation of pleural fluid is the main diagnostic method. However, cytological evaluation is 60% sensitive for diagnosis. The presence of tumor cells in pleural effusion has diagnostic value in malignant pleural effusions; however, the chance of finding tumor cells in the fluid is low (1). Since the pleural biopsy performed in the study was a blind biopsy, the probability of finding pathological tissue in the pleura would also be low. There is a higher chance of finding tumor markers instead (2). In a retrospective study conducted by us in 2022, it was revealed that immature granulocyte levels contributed to the diagnosis of malignant pleural effusion (1). The author's study has shown once again that the probability of finding malignant cells in malignant pleural effusions is low even with repeated thoracentesis. Not every patient may be clinically suitable for surgical biopsy. Some malignancies may show low 18-Fludeoxyglucose uptake in positron emission tomography. In this case, less invasive peripheral markers can also be used in diagnosis. Sincerely.