Clinical Characteristics of Mediastinal Paragangliomas: A retrospective study

Studies focusing on mediastinal paragangliomas are limited. In this study, we describe the clinical, pathological, and genetic characteristics of mediastinal paragangliomas.

Clinical data from all patients with extrapericardial mediastinal paragangliomas at a single center were retrospectively analyzed. Germline variants were assessed using next-generation sequencing and Sanger sequencing of blood samples. Patients were grouped according to genetic variants and tumor location, and clinical characteristics were compared.

22 patients (male:female ratio, 8:14) were included in the study, with a mean age of 41.4 years. Hypertension was present in 16 patients (72.7%), and 13 (59.1%) exhibited typical catecholamine-related symptoms. Tumors were located in the anterior, middle, and posterior mediastinum in 1 (4.5%), 4 (18.2%), and 17 (77.3%) cases, with an average size of 5.3±1.7 cm. Multiple tumors were identified in 6 patients. Catecholamine-producing tumors were observed in 17/21 (81.0%) patients. Surgical resection was performed in 20 (90.9%) patients. No postoperative local recurrences were observed. Metastasis occurred in 2/18 (11.1%) cases. Eleven patients underwent genetic testing; six harbored SDHx mutations. Compared with anterior and middle mediastinal tumors, posterior mediastinal tumors were associated with higher rates of typical symptoms (12/17 vs. 1/5, p = 0.043) and catecholamine-producing function (17/17 vs. 0/4, p < 0.001), as well as higher levels of 24-hour urinary norepinephrine (5.10 × ULN vs. 0.56 × ULN, p = 0.037).

Mediastinal paragangliomas are rare and are frequently associated with SDHx variants. Posterior mediastinal tumors are predominantly functional and noradrenergic; recognizing these features may facilitate diagnosis.