A type of carcinoma of the kidney with origin in the epithelium of the proximal convoluted renal tubule.

A type of carcinoma of the kidney with origin in the epithelium of the proximal convoluted renal tubule.

Von Hippel-Lindau syndrome (VHL) is characterized by hemangioblastomas of the brain, spinal cord, and retina; renal cysts and clear cell renal cell carcinoma; pheochromocytoma and paraganglioma; pancreatic cysts and neuroendocrine tumors; endolymphatic sac tumors; and epididymal and broad ligament cystadenomas. Retinal hemangioblastomas may be the initial manifestation of VHL and can cause vision loss. 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. 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.

Lynch syndrome is characterized by an increased risk for colorectal cancer (CRC) and cancers of the endometrium, ovary, stomach, small bowel, urinary tract, biliary tract, brain (usually glioblastoma), skin (sebaceous adenomas, sebaceous carcinomas, and keratoacanthomas), pancreas, and prostate. Cancer risks and age of onset vary depending on the associated gene. Several other cancer types have been reported to occur in individuals with Lynch syndrome (e.g., breast, sarcomas, adrenocortical carcinoma). However, the data are not sufficient to demonstrate that the risk of developing these cancers is increased in individuals with Lynch syndrome.

FH tumor predisposition syndrome is characterized by cutaneous leiomyomata, uterine leiomyomata (fibroids), and/or renal tumors. Pheochromocytoma and paraganglioma have also been described in affected individuals from a small number of families with specific FH pathogenic variants. Cutaneous leiomyomata appear as skin-colored to light brown papules or nodules distributed across the trunk and extremities and occasionally on the face, and are usually noted in the second to fourth decades of life, increasing in size and number with age. Uterine leiomyomata tend to be numerous and large; mean age at diagnosis is ~30 years, with most females experiencing irregular or heavy menstruation and pelvic pain. Renal tumors are usually unilateral, solitary, and aggressive. They are associated with poor survival due to clinical aggressiveness and propensity to metastasize despite small primary tumor size. The median age of detection is approximately 40 years.

Tuberous sclerosis complex (TSC) involves abnormalities of the skin (hypomelanotic macules, confetti skin lesions, facial angiofibromas, shagreen patches, fibrous cephalic plaques, ungual fibromas); brain (subependymal nodules, cortical tubers, and subependymal giant cell astrocytomas [SEGAs], seizures, TSC-associated neuropsychiatric disorder [TAND]); kidneys (benign renal angiomyolipomas, epithelial cysts, oncocytoma, renal cell carcinoma); heart (rhabdomyomas, arrhythmias); and lungs (lymphangioleiomyomatosis [LAM], multifocal micronodular pneumonocyte hyperplasia). Central nervous system-related problems (including TAND) are the leading cause of morbidity, whereas kidney disease is the leading cause of mortality.

Tuberous sclerosis complex (TSC) involves abnormalities of the skin (hypomelanotic macules, confetti skin lesions, facial angiofibromas, shagreen patches, fibrous cephalic plaques, ungual fibromas); brain (subependymal nodules, cortical tubers, and subependymal giant cell astrocytomas [SEGAs], seizures, TSC-associated neuropsychiatric disorder [TAND]); kidneys (benign renal angiomyolipomas, epithelial cysts, oncocytoma, renal cell carcinoma); heart (rhabdomyomas, arrhythmias); and lungs (lymphangioleiomyomatosis [LAM], multifocal micronodular pneumonocyte hyperplasia). Central nervous system-related problems (including TAND) are the leading cause of morbidity, whereas kidney disease is the leading cause of mortality.

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 paragangliomas [HNPGLs]) and sometimes in the upper mediastinum; approximately 95% of such tumors are nonsecretory. In contrast, extra-adrenal sympathetic 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/PCCs 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. Additional tumors reported in individuals with hereditary PGL/PCC syndromes include gastrointestinal stromal tumors (GISTs), pulmonary chondromas, and clear cell renal cell carcinoma.

Xp11 translocation renal cell carcinomas (RCCX1) are a group of neoplasms distinguished by chromosomal translocations with breakpoints involving the TFE3 gene within tumor cells. The result is a TFE3 transcription factor gene fusion with 1 of multiple reported genes including ASPRCR1 (606236) on chromosome 17q25 and PRCC (179755) on 1q21, and more rarely, NONO (300084) on Xq13, SFPQ (605199) on 1p34, CLTC (118955) on 17q23, and unknown genes on chromosomes 3 and 10. Xp11 translocations are often found in pediatric tumors and less commonly in adults. However, adult cases may outnumber pediatric cases since renal cell carcinoma is more common in the adult population. Prior chemotherapy is a known risk factor for Xp11 translocations. Histology shows both clear cells and papillary architecture, often with abundant psammoma bodies, although variable histologic features have been observed (review by Ross and Argani, 2010). For a discussion of genetic heterogeneity of renal cell carcinoma, see RCC (144700).

BAP1 tumor predisposition syndrome (BAP1-TPDS) is associated with an increased risk for a specific skin lesion, BAP1-inactivated melanocytic tumors (BIMT; formerly called atypical Spitz tumors), and the following cancers, in descending order of frequency: uveal (eye) melanoma (UM), malignant mesothelioma (MMe), cutaneous melanoma (CM), renal cell carcinoma (RCC), basal cell carcinoma (BCC), meningioma, and cholangiocarcinoma. Onychopapillomas, hepatocellular carcinoma, and ovarian sex cord-stromal tumors may also be associated with BAP1-TPDS. Affected individuals can have more than one type of primary cancer. In general, the median age of onset of these tumors is younger than in the general population. UM tends to be a more aggressive class 2 tumor with higher risk for metastasis and reduced survival compared to UM occurring in the general population. RCC is usually of clear cell morphology, but other pathologies have been reported. MMe, especially pleural, has better survival and responds better to platinum chemotherapy than MMe not associated with a germline BAP1 pathogenic variant. The penetrance, natural history, life-time cancer risk for carriers, and frequencies of BAP1-associated tumors are yet to be fully determined.

The features of Cowden syndrome overlap with those of another disorder called Bannayan-Riley-Ruvalcaba syndrome. People with Bannayan-Riley-Ruvalcaba syndrome also develop hamartomas and other noncancerous tumors.  Some people with Cowden syndrome have relatives diagnosed with Bannayan-Riley-Ruvalcaba syndrome, and other affected individuals have the characteristic features of both conditions. Based on these similarities, researchers have proposed that Cowden syndrome and Bannayan-Riley-Ruvalcaba syndrome represent a spectrum of overlapping features known as PTEN hamartoma tumor syndrome (named for the genetic cause of the conditions) instead of two distinct conditions.\n\n\n\nSome people do not meet the strict criteria for a clinical diagnosis of Cowden syndrome, but they have some of the characteristic features of the condition, particularly the cancers. These individuals are often described as having Cowden-like syndrome. Both Cowden syndrome and Cowden-like syndrome are caused by mutations in the same genes.\n\nCowden syndrome is associated with an increased risk of developing several types of cancer, particularly cancers of the breast, a gland in the lower neck called the thyroid, and the lining of the uterus (the endometrium). Other cancers that have been identified in people with Cowden syndrome include kidney cancer, colorectal cancer, and an agressive form of skin cancer called melanoma. Compared with the general population, people with Cowden syndrome develop these cancers at younger ages, often beginning in their thirties or forties. People with Cowden syndrome are also more likely to develop more than one cancer during their lifetimes compared to the general population. Other diseases of the breast, thyroid, and endometrium are also common in Cowden syndrome. Additional signs and symptoms can include an enlarged head (macrocephaly) and a rare, noncancerous brain tumor called Lhermitte-Duclos disease. A small percentage of affected individuals have delayed development, intellectual disability, or autism spectrum disorder, which can affect communication and social interaction.\n\nAlmost everyone with Cowden syndrome develops hamartomas. These growths are most commonly found on the skin and mucous membranes (such as the lining of the mouth and nose), but they can also occur in the intestine and other parts of the body. The growth of hamartomas on the skin and mucous membranes typically becomes apparent by a person's late twenties.\n\nCowden syndrome is a genetic disorder characterized by multiple noncancerous, tumor-like growths called hamartomas and an increased risk of developing certain cancers.

The clinical characteristics of Birt-Hogg-Dubé syndrome (BHDS) include cutaneous manifestations (fibrofolliculomas, acrochordons, angiofibromas, oral papules, cutaneous collagenomas, and epidermal cysts), pulmonary cysts / history of pneumothorax, renal cysts, and various types of renal tumors. Disease severity can vary significantly even within the same family. Skin lesions typically appear between the second and fourth decades of life and typically increase in size and number with age. Lung cysts are mainly in the basal lung regions; most individuals are asymptomatic but at high risk for spontaneous pneumothorax. Renal tumors can be bilateral and multifocal. The most common renal tumors are a hybrid of oncocytoma and chromophobe histologic cell types (oncocytic hybrid tumor); clear cell carcinoma and oncocytoma are also common.