title: Renal tumors associated with germline SDHB mutation show distinctive morphology.
abstract: Germline succinate dehydrogenase B (SDHB) mutation causes pheochromocytoma/paraganglioma syndrome type 4 (PGL4). PGL4 is characterized by pheochromocytoma and paraganglioma, type 2 (SDHB negative) gastrointestinal stromal tumors and renal tumors, which are usually classified as carcinoma. We report 4 kindreds with 5 PGL4-associated renal tumors. Four of the tumors occurred before the age of 30 years, 4 were in the left kidney, 3 were in female patients, and 4 demonstrated consistent but previously unrecognized morphology. The tumors were composed of cuboidal cells with bubbly eosinophilic cytoplasm and indistinct cell borders. Many of the cells displayed distinctive cytoplasmic inclusions, which were vacuolated or contained eosinophilic fluid-like material. The cells were arranged in solid nests or in tubules surrounding central spaces. The tumors were well circumscribed or lobulated and frequently showed cystic change. Benign tubules or glomeruli were often entrapped at the edges of the tumors. The fifth tumor lacked these features but displayed sarcomatoid dedifferentiation. Immunohistochemistry for SDHB was completely negative in all 4 available tumors. Death from metastatic disease occurred in the patient with dedifferentiated tumor 1 year after diagnosis, whereas the other 4 tumors were cured by local excision alone (mean follow-up, 11 y; range, 2 to 30 y). We conclude that morphology supported by negative immunohistochemistry for SDHB can be used to identify kindreds with germline SDHB mutations (PGL4 syndrome) presenting with this unique type of renal tumor. These renal tumors appear to have a good prognosis after complete excision unless there is sarcomatoid dedifferentiation.
authors.affiliation: Department of Anatomical Pathology, Royal North Shore Hospital, St Leonards, NSW, 2065, Australia. affgill@med.usyd.edu.au
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Gill
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Pachter
authors.forename: Angela
authors.initials: A
authors.lastname: Chou
authors.forename: Barbara
authors.initials: B
authors.lastname: Young
authors.forename: Adele
authors.initials: A
authors.lastname: Clarkson
authors.forename: Katherine M
authors.initials: KM
authors.lastname: Tucker
authors.forename: Ingrid M
authors.initials: IM
authors.lastname: Winship
authors.forename: Peter
authors.initials: P
authors.lastname: Earls
authors.forename: Diana E
authors.initials: DE
authors.lastname: Benn
authors.forename: Bruce G
authors.initials: BG
authors.lastname: Robinson
authors.forename: Stewart
authors.initials: S
authors.lastname: Fleming
authors.forename: Roderick J
authors.initials: RJ
authors.lastname: Clifton-Bligh
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000556:secondary* / Q000601:surgery; D000328:Adult; D005260:Female; D018095:Germ-Line Mutation; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010235:Paraganglioma / Q000473:pathology; D010673:Pheochromocytoma / Q000473:pathology; D011379:Prognosis; D013385:Succinate Dehydrogenase / Q000235:genetics*; D055815:Young Adult
chemical_list: C108095:SDHB protein, human; D013385:Succinate Dehydrogenase