Role of PET CT in Evaluation of Benign and Malignant Mediastinal Lesions

Abstract Background: The histological and radiological range of mediastinal malignancies is broad. Malignancies are more likely to occur in the anterior compartment, despite the fact that more than two-thirds of these tumors are benign. FDG PET/CT may be used in conjunction with other imaging techniques to assess mediastinal masses. In patients with non-avid or low avid FDG lesions, PET/CT may reduce the need for invasive diagnostic procedures. However, for a definitive diagnosis, confirmation tissue sample is required to confirm PET positive findings. Aim of Study: The aim of the study is to investigate the ability of PET-CT in differentiation between benign and malignant mediastinal masses, which is subsequently reflected in the management of mediastinal masses in these patients. Patients and Methods: This is a prospective study. After their kind was established by histological investigation, the PET scans of 30 lesions/malignant and benign tumors were analyzed in the mediastinum, taking into account the patients' age and gender as well as the tumor's specific position in the mediastinum. Patients were referred to private center for PET CT scan of the chest over a period of 12 months (July 2019 to June 2020). Results: The patients were divided into groups based on their histological diagnosis. Lymphoma (26%) was the most common type of lesion, followed by Bronchogenic carcinoma (10%), metastatic lymph nodes (26%), thymic tumors (20%), germ cell tumours (3.3%), teratoma (3.3%), neuroendocrine tumors (3.3%), retrosternal thyroid lesions (3.3%), tracheal mass (3.3%), esophageal mass (3.3%), and sarcoidosis (6.6%). Conclusions: For the evaluation of benign and malignant mediastinal masses, FDG PET/CT is a useful addition to traditional imaging approaches. In patients with non-avid or low avid FDG lesions, PET/CT decreases the need for invasive diagnostic procedures. However, for a definitive diagnosis, confirmation tissue sample is required to confirm PET positive findings.