Use of PET/CT in Diagnosis and Staging of Malignant Pleural Mesothelioma

Abstract

he pleural space is formed by two pleural membranes: the parietal pleura and the visceral pleura. Each is comprised of a single layer of mesothelial cells, a basement membrane, and a layer of connective tissue which contains blood vessels and lymphatics. Various benign, malignant, and tumor-like conditions can involve the pleura. Malignant neoplasms are more common than benign neoplasms. Pleural tumors can have a varied imaging spectrum – may be unilateral or bilateral, calcified, or noncalcified, and focal or diffuse. Malignant pleural mesothelioma (MPM) is an aggressive tumor that arises from mesothelial cells lining the pleural cavity. Its occurrence is related to exposure to mineral fibers, particularly asbestos, which represents the main risk for MPM, with a latency period of approximately 40 years between fiber exposure and disease presentation. Mesothelioma, the cancerous transformation of the mesothelium, can affect various serosal surfaces, and is most commonly associated with occupational or environmental asbestos exposure, often after a lag time of 20 to 40 years since the first exposure. Mesothelioma is estimated to kill 38,400 people per year worldwide, based on extrapolations for asbestos use.