Von Hippel-Lindau (VHL) syndrome is characterized by hemangioblastomas of the brain, spinal cord, and retina; renal cysts and clear cell renal cell carcinoma; pheochromocytoma, pancreatic cysts, and neuroendocrine tumors; endolymphatic sac tumors; and epididymal and broad ligament cysts. Cerebellar hemangioblastomas may be associated with headache, vomiting, gait disturbances, or ataxia. Spinal hemangioblastomas and related syrinx usually present with pain. Sensory and motor loss may develop with cord compression. Retinal hemangioblastomas may be the initial manifestation of VHL syndrome and can cause vision loss. Renal cell carcinoma occurs in about 70% of individuals with VHL and is the leading cause of mortality. Pheochromocytomas can be asymptomatic but may cause sustained or episodic hypertension. Pancreatic lesions often remain asymptomatic and rarely cause endocrine or exocrine insufficiency. Endolymphatic sac tumors can cause hearing loss of varying severity, which can be a presenting symptom. Cystadenomas of the epididymis are relatively common. They rarely cause problems, unless bilateral, in which case they may result in infertility.

A familial syndrome characterized by gastrointestinal stromal tumors and paragangliomas, often at multiple sites. It is a very rare syndrome presenting at a young age. The gastric stromal sarcomas are multifocal and the paragangliomas are multicentric. The clinical spectrum of this syndrome varies widely, depending on the localization and the size of the tumors. The vast majority of cases are due to germline mutations of the succinate dehydrogenase (SDH) subunit genes SDHB, SDHC and SDHD. Predisposition to developing these tumors is inherited in an autosomal dominant manner with incomplete penetrance.

Hereditary paraganglioma-pheochromocytoma (PGL/PCC) syndromes are characterized by paragangliomas (tumors that arise from neuroendocrine tissues distributed along the paravertebral axis from the base of the skull to the pelvis) and pheochromocytomas (paragangliomas that are confined to the adrenal medulla). Sympathetic paragangliomas cause catecholamine excess; parasympathetic paragangliomas are most often nonsecretory. Extra-adrenal parasympathetic paragangliomas are located predominantly in the skull base and neck (referred to as head and neck PGL [HNPGL]) and sometimes in the upper mediastinum; approximately 95% of such tumors are nonsecretory. In contrast, sympathetic extra-adrenal paragangliomas are generally confined to the lower mediastinum, abdomen, and pelvis, and are typically secretory. Pheochromocytomas, which arise from the adrenal medulla, typically lead to catecholamine excess. Symptoms of PGL/PCC result from either mass effects or catecholamine hypersecretion (e.g., sustained or paroxysmal elevations in blood pressure, headache, episodic profuse sweating, forceful palpitations, pallor, and apprehension or anxiety). The risk for developing metastatic disease is greater for extra-adrenal sympathetic paragangliomas than for pheochromocytomas.

Hereditary paraganglioma-pheochromocytoma (PGL/PCC) syndromes are characterized by paragangliomas (tumors that arise from neuroendocrine tissues distributed along the paravertebral axis from the base of the skull to the pelvis) and pheochromocytomas (paragangliomas that are confined to the adrenal medulla). Sympathetic paragangliomas cause catecholamine excess; parasympathetic paragangliomas are most often nonsecretory. Extra-adrenal parasympathetic paragangliomas are located predominantly in the skull base and neck (referred to as head and neck PGL [HNPGL]) and sometimes in the upper mediastinum; approximately 95% of such tumors are nonsecretory. In contrast, sympathetic extra-adrenal paragangliomas are generally confined to the lower mediastinum, abdomen, and pelvis, and are typically secretory. Pheochromocytomas, which arise from the adrenal medulla, typically lead to catecholamine excess. Symptoms of PGL/PCC result from either mass effects or catecholamine hypersecretion (e.g., sustained or paroxysmal elevations in blood pressure, headache, episodic profuse sweating, forceful palpitations, pallor, and apprehension or anxiety). The risk for developing metastatic disease is greater for extra-adrenal sympathetic paragangliomas than for pheochromocytomas.

Hereditary paraganglioma-pheochromocytoma (PGL/PCC) syndromes are characterized by paragangliomas (tumors that arise from neuroendocrine tissues distributed along the paravertebral axis from the base of the skull to the pelvis) and pheochromocytomas (paragangliomas that are confined to the adrenal medulla). Sympathetic paragangliomas cause catecholamine excess; parasympathetic paragangliomas are most often nonsecretory. Extra-adrenal parasympathetic paragangliomas are located predominantly in the skull base and neck (referred to as head and neck PGL [HNPGL]) and sometimes in the upper mediastinum; approximately 95% of such tumors are nonsecretory. In contrast, sympathetic extra-adrenal paragangliomas are generally confined to the lower mediastinum, abdomen, and pelvis, and are typically secretory. Pheochromocytomas, which arise from the adrenal medulla, typically lead to catecholamine excess. Symptoms of PGL/PCC result from either mass effects or catecholamine hypersecretion (e.g., sustained or paroxysmal elevations in blood pressure, headache, episodic profuse sweating, forceful palpitations, pallor, and apprehension or anxiety). The risk for developing metastatic disease is greater for extra-adrenal sympathetic paragangliomas than for pheochromocytomas.

Pheochromocytoma/paraganglioma syndrome-6 (PPGL6) is an autosomal dominant adult-onset tumor predisposition syndrome in which affected individuals develop neuroendocrine neoplasms, known as paragangliomas. Many tumors arise in the abdomen, although some may arise in other regions, including the head and neck. Some of the tumors may secrete biologically active normetanephrines, resulting in secondary hypertension. Tumors may be benign or malignant, and some may metastasize (summary by Buffet et al., 2018). For a discussion of genetic heterogeneity of pheochromocytoma/paraganglioma syndrome, see PPGL1 (168000).

Pheochromocytoma/paraganglioma syndrome-7 (PPGL7) is an autosomal dominant tumor predisposition syndrome in which affected individuals develop adult-onset neuroendocrine neoplasms, known as paragangliomas. Most tumors arise in the abdomen, secrete normetanephrine, and follow a benign disease course (summary by Remacha et al., 2019). For a discussion of genetic heterogeneity of pheochromocytoma/paraganglioma syndrome, see PPGL1 (168000).