Advisory Committee Chair
Advisory Committee Members
Date of Award
Degree Name by School
Doctor of Philosophy (PhD) School of Public Health
ABSTRACT Pheochromocytomas and extra-adrenal paragangliomas (PGLs) are forms of neuroendocrine tumors which when left untreated lead to debilitating complications of cerebral hemorrhaging, stroke, and death. Typically, the tumors present with symptoms of episodic headaches, sweating, and palpitations, however hypertension is considered one of the more predominant signs. As a result of the rarity of the disease and wide range of symptoms, there are often difficulties in screening and diagnosis to identify these tumors. While there are many case studies and results in small populations, large epidemiologic driven studies are limited. To date the majority of large-scale studies exist in countries with large national health records databases, with the larger studies from the United States (US) limited to a few follow-up studies and Surveillance, Epidemiology, and End Results (SEER) Program based studies. Much is known about genetic and familial disorders that are associated with the development of these tumors, but there exists wide variation the current literature focused on the characteristics and outcomes related to these rare tumors. Therefore, the goal of this dissertation is to examine pheochromocytomas and PGLs across several populations to improve the knowledge around diagnosis, treatment, and risk factors related to these tumors. Utilizing a large national sample of cases from the National Cancer Database (NCDB) as well as a population of cases from a large academic medical center, this research will provide one of the more comprehensive reviews of pheochromocytoma and PGL presented in the US. Results observed both similarities and differences across the two tumor types in all study populations, with greater differences observed among the treatment modalities and tumor characteristics. Among the NCDB cases, size of the tumor was shown to be different, but metastatic disease provided the strongest effect on survival. Among surgical cases no significant difference in mortality was observed between the two tumor types. Additional risk factors and biomarkers associated with pheochromocytomas and PGLs were suggested, particularly for specific the hypertensive medications, with less common antihypertensive prescriptions of Clonidine, Atenolol, and Labetalol suggesting an association with diagnosis. This dissertation provides a greater understanding of pheochromocytomas and PGLs, providing significant results to inform the early detection and clinical care of individuals with these tumors. Keywords: pheochromocytoma, paraganglioma, hypertension, surgery, biomarker
Singletary, Brandon A., "Pheochromocytoma: A Systematic Review Of The Diagnosis, Treatment, And Risk Factors" (2020). All ETDs from UAB. 917.