Application of the international system for reporting serous fluid cytopathology on pleural effusion cytology with paired pleural biopsy: A new insight and novel approach on risk of malignancy.

This study demonstrates the high specificity and ROM for 'malignant' and 'suspicious for malignancy' categories in the TIS reporting system and highlights the modest negative predictive value for the 'negative for malignancy' category. Although Tissue biopsies are usually considered as 'gold standard', any definitive diagnosis of malignancy of body fluid should be considered positive for malignancy in further clinical decision-making.