Paragangliomas of the head and neck. Epidemiology and diagnosis

BACKGROUND: Head and neck tumors cross several clinical specialties. Diagnostic and treatment approaches vary significantly depending on specialty, and there is no a unified diagnostic standard for paragangliomas in these areas. In this report, we summarize available data on these tumors and present own patient evaluation protocol. OBJECTIVE: To systematize modern information on epidemiology, pathogenesis and diagnosis of paragangliomas. MATERIAL AND METHODS: We present literature review and retrospective analysis of instrumental and laboratory data of patients with head and neck paragangliomas. RESULTS: We analyzed modern diagnostic methods: imaging (Doppler ultrasound, CT, MRI, PET CT), biochemical (catecholamines and their metabolites), and molecular genetic (mutation testing) tests. Advantages and limitations of each method were identified. We also present optimal algorithms for their combination for early and accurate disease detection. CONCLUSION: This analysis systematized the approach to diagnostic algorithm for patients with head and neck paragangliomas. The capabilities of modern imaging methods allow for identification of potentially malignant and familial forms of disease, which are fundamentally different from sporadic forms. Available data underlie a differentiated approach to treatment strategy. This positively impacts treatment outcomes. This aspect will be discussed in the second part of the article.