Paragangliomas (PGLs) are rare neuroendocrine tumors that arise in sympathetic and parasympathetic paraganglia and derive from neural crest cells. Malignancy is defined by presence of metastases, tumor spread in sites where chromaffin tissue is normally absent such as lymph nodes, liver, lungs, and bones. Malignant PGLs are extremely rare. The pathogenesis and progression of PGLs are very strongly influenced by genetics. A germline mutation in one of the susceptibility genes identified so far explains ~40% of all cases; the remaining 60% are thought to be sporadic cases. Sporadic as well as hereditary PGLs have been divided in two main clusters linked to two different signalling pathways: the first cluster contains all VHL-, SDHx-, and FH- mutated tumors and is associated to the activation of hypoxic pathway, while the second cluster contains all RET- , NF1-, MAX and TMEM127- mutated tumors and is associated to the activation of MAPK and mTOR (mammalian target of rapamycin) signaling pathways.
Category
Cancer
Brite
Human diseases in ICD-11 classification [BR:br08403]
02 Neoplasms
Malignant neoplasms, except primary neoplasms of lymphoid, haematopoietic, central nervous system or related tissues
Malignant neoplasms, stated or presumed to be primary, of specified sites, except of lymphoid, haematopoietic, central nervous system or related tissues
Malignant neoplasms of endocrine glands
2D12 Malignant neoplasms of other endocrine glands or related structures
H01510 Malignant paraganglioma
Pathway-based classification of diseases [BR:br08402]
Signal transduction
nt06526 MAPK signaling
H01510 Malignant paraganglioma
Cellular process
nt06523 Epigenetic regulation by Polycomb complexes
H01510 Malignant paraganglioma
Medullary thyroid carcinoma (MTC) is a malignant tumor originating from thyroid parafollicular C cells and accounts for only <5% of thyroid cancers, but it causes a disproportionate number of thyroid cancer deaths due to its more aggressive clinical behavior compared with well-differentiated papillary and follicular thyroid carcinomas. A subset of MTC cases is hereditary and due to germline mutations in the RET tyrosine kinase receptor gene. Somatic mutations in either RET or RAS are also present in most sporadic tumors. In MTC, RET mutations lead to substrate-independent dimerization of the receptor causing constitutive activation, unrestricted signaling, and ultimately, cancer.
Category
Cancer
Brite
Human diseases in ICD-11 classification [BR:br08403]
02 Neoplasms
Malignant neoplasms, except primary neoplasms of lymphoid, haematopoietic, central nervous system or related tissues
Malignant neoplasms, stated or presumed to be primary, of specified sites, except of lymphoid, haematopoietic, central nervous system or related tissues
Malignant neoplasms of endocrine glands
2D10 Malignant neoplasms of thyroid gland
H01592 Medullary thyroid cancer
Pathway-based classification of diseases [BR:br08402]
Signal transduction
nt06526 MAPK signaling
H01592 Medullary thyroid cancer
Tumor markers [br08442.html]
H01592