In the era of personalised medicine, is pleural fluid cytology sufficient for oncological treatment?

Abstract

Introduction: Pleural fluid (PF) cytology was previously sufficient to guide oncological treatment. In the current field of personalised medicine, this may not be the case and it is frequently necessary to obtain a tissue sample even when the PF cytology demonstrates malignant cells. This raises the question of the role of PF cytology in the diagnostic pathway of patients with malignant pleural effusion. Aims & Method: All patients who had a procedure performed by the pleural service between 2015 - 2017 were included. Those with PF demonstrating malignant cells were reviewed to determine whether further tissue was required. Those with concurrent pleural histological samples were excluded. Results: 107 patients had positive PF cytology. No further testing was needed in 49 patients; 33 already had a pathological diagnosis and 16 were too unwell for treatment or followed up elsewhere. PF was sufficient to test for receptor or mutation status in 33/58 (57%) patients, 19 (33%) required further pleural biopsies and 6 (10%) underwent alterative procedures to obtain tissue. 52/58 patients had adenocarcinoma cells in the PF. Conclusions: PF cytology was sufficient for definitive oncological treatment in 57% of patients. Further work is needed to determine characteristics which would highlight which patients are likely to need further tests to guide treatments and in which patients PF will be sufficient.