Causes of Isolated Mediastinal Lymphadenopathy: Analysis of 348 Cervical Mediastinoscopy Patients.

Objective: This study was designed to investigate the causes of isolated mediastinal lymphadenopathy, the role of cervical mediastinoscopy (CM) in the diagnosis, and the accuracy of computed tomography (CT) to predict malign and benign pathology in patients with isolated mediastinal lymphadenopathy. Materials and Methods: The records of 348 patients who underwent CM for isolated mediastinal lymphadenopathy between 2006 and 2018 were analyzed. The group comprised 189 males and 159 females. The cases were evaluated in terms of age, distribution of lymph node stations in which lymphadenopathy was detected and sampled, mortality, morbidity, and histopathological diagnostic parameters. Results: The median age of the patients was 48 years (min--max: 18--79 years). The median lymph node diameter was 2 cm (min--max: 1--6 cm). Lymphadenopathy was found in a total of 724 lymph node stations. The median lymph node diameter was 3.7 cm in patients with malignant disease and 2 cm in cases of benign disease. The reliability of CT to predict malignancy was 76.8% specificity and 71.1% sensitivity when the lymph node diameter was >2.5 cm (area under the curve: 0.820; 95% confidence interval: 0.774--0.860; p<0.001). Complications occurred in 2 cases, however, no mortality was observed. The histopathological results were sarcoidosis (43.1%), tuberculosis (TB) (20.7%), reactive hyperplasia (14.7%), carcinoma metastasis (8.6%), lymphoma (6%), and other (6.8%). Conclusion: Although sarcoidosis is the most common cause of isolated mediastinal lymphadenopathy, TB is still prevalent in Türkiye. The sensitivity of CT imaging to identify malignancy increased with a larger lymph node diameter. CM is a safe and effective diagnostic procedure for patients with mediastinal lymphadenopathy. [ABSTRACT FROM AUTHOR]