Mesothelioma Diagnosis & Tests - Cytology Unlike imaging tests, cytology is a pathological means to diagnosing malignant mesothelioma in patients, consisting of a fluid biopsy of abnormalities previously discovered. Once cytology is performed, the cells from the sample are examined to arrive at a diagnosis. There are two types of cytology that can be performed- Paracentisis and Thoracentisis. PARACENTISIS Paracentisis refers to a biopsy of fluid that has collected in the belly (peritoneal fluid). Apart from an interventional radiologist (IR) initially cleaning the area to be tested, there is no preparation for the procedure required from the patient. During Paracentisis, the patient will be under local anesthesia at the site of the targeted area. A needle will be injected into the targeted area being tested and will extract the fluid with which the cytology is to be performed. THORACENTISIS Thoracentisis refers to a biopsy of fluid that has collected within the pleur...