Is Regional Lymph Node Metastasis of Head and Neck Paraganglioma a Sign of Aggressive Clinical Behavior: A Clinical/Pathologic Review

Background: Head and neck paraganglioma is a rare neoplasm of the paraganglia. It accounts for <1% of all head and neck tumors. It usually has benign clinical course; however, malignant paraganglioma can only be diagnosed by showing metastatic disease. We undertook a retrospective study to assess the clinical significance of regional lymph nodes metastases in head and neck paragangliomas. Design: From 1993 to 2016, primary head and neck paragangliomas are identified. The patient clinical and histopathologic materials were reviewed. Results: Sixty-five specimens from 62 patients (3 patients with more than 1 specimens) with head and neck paragangliomas were recorded (49 female and 13 males) with mean age of 54 (24-78 years). The locations of the tumors were as follows: carotid body: 30, glomus tympanicum: 11, glomus jugulare: 14, parapharyngeal space: 3, and 1 case each of larynx, skull base, paraglottic area, infratemporal fossa, mastoid, cerebellopontine (CP) angle, and pyriform sinus. On histopathology, we found 5 cases of sclerosing variant. Thirty-two (52%) of the 62 patients had regional lymph node biopsy. Four (12%) of the 32 show metastatic paraganglioma (3 females and 1 male with mean age = 35). Two of the 5 cases of sclerosing variant had positive lymph nodes. No evidence of local recurrence or distant metastasis in the patients with positive lymph nodes with a 6 to 11 years follow-up. One of the 28 patients with negative lymph nodes developed metastatic disease to lumbar spine in 5 years. Conclusion: Metastatic paraganglioma to regional lymph nodes may have indolent clinical behavior, with disease-free survival of up to 11 years. The incidence of metastatic disease in lymph nodes was 4 (12%) of 32. Forty percent (2/5) of the cases with sclerosing variant of paraganglioma had lymph node metastases indicating that this tumor may have a more aggressive histological behavior.