Pheochromocytoma classification
Pheochromocytoma Microchapters |
Diagnosis |
---|
Treatment |
Case Studies |
Pheochromocytoma classification On the Web |
American Roentgen Ray Society Images of Pheochromocytoma classification |
Risk calculators and risk factors for Pheochromocytoma classification |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ahmad Al Maradni, M.D. [2]
Please help WikiDoc by adding content here. It's easy! Click here to learn about editing.
Overview
Pheochromocytoma can be either benign or malignant and can be localized, regional, or metastatic. It can be familial, non-familial and sporadic.
Classification
- Pheochromocytoma may be classified by nature either:
- Benign
- malignant: 10% of pheochromocytomas are malignant.
- Malignant and benign tumours share the same biochemical and histological characters,the only difference is the ability of the malignant tumor to invade local and distatant tissues.(WHO Classification of Tumours, DeLellis RA, Lloyd RV, Heitz PU, Eng C. (Eds), IARC press, Lyon, France 2004)
- Most cases need follow up for long durations.
Pheochromocytomas can be classified by spread ability either:
- localized: 95 *% of pheochromocytomas are in the abdomen, 85 to 90 % are intraadrenal and 5 to 10 percent are multiple, 10% are extraadrenal and are referred to as catecholamine-secreting paragangliomas.
- regional
- metastatic
Pheochromocytoma can be either familial,non-familial or sporadic:
- Familial pheochromocytoma is an autosomal dominant disorder characterized by skull, neck, thorax, abdomen and urinary bladder. They are associated with other syndromes named Multiple endocrien neoplasia (MEN2) Which are autosomal dominant syndromes controlled by RET gene. Pheochromocytoma occurs in 50% of patients with MEN2 as follows:
MEN1 | MEN2 |
---|---|
|
|
- Non-familial pheochromocytoma: majority of them are positive for KIT expression, some are not. A partial explanation was provided by the finding of activating mutations in another gene encoding an RTK, the platelet-derived growth factor receptor alpha (PDGFRA) gene in some KIT-negative GISTs
- cholelithiasis
- renal artery stenosis
- (gastrointestinal stromal tumor [GIST]
- paraganglioma
- adrenal cortical adenoma
Sporadic: Most catecholamine-secreting tumors are sporadic.Mutations were identified in most of sporadic cases. May be due to spontaneous mutation, decreased penetrance, maternal imprinting.[1] 50% of patients had a pathogenic mutation in SDHB, SDHD, or VHL[2]
Pheochromocytoma can be classified on genetic basis into cluster 1 and cluster 2 :
Cluster 1 tumorsare noradrenergic. Cluster 2 tumors are adrenergic.[3]
Cluster 1 | Cluster 2 |
---|---|
|
|
. Patients with the succinate dehydrogenase B mutations are likely to develop malignant disease.[4]
References
- ↑ Buffet A, Venisse A, Nau V, Roncellin I, Boccio V, Le Pottier N; et al. (2012). "A decade (2001-2010) of genetic testing for pheochromocytoma and paraganglioma". Horm Metab Res. 44 (5): 359–66. doi:10.1055/s-0032-1304594. PMID 22517557.
- ↑ Jafri M, Whitworth J, Rattenberry E, Vialard L, Kilby G, Kumar AV; et al. (2013). "Evaluation of SDHB, SDHD and VHL gene susceptibility testing in the assessment of individuals with non-syndromic phaeochromocytoma, paraganglioma and head and neck paraganglioma". Clin Endocrinol (Oxf). 78 (6): 898–906. doi:10.1111/cen.12074. PMID 23072324.