title: Foamy cell (hibernoma-like) change is a rare histopathological feature in renal cell carcinoma.
abstract: We report nine patients (seven males and two females, median age 64 years (range 51-79 years)) with a renal cell carcinoma, each of which contained a significant component of neoplastic epithelial cells with a striking microvacuolated (hibernoma-like) cytoplasmic appearance. Tumor sizes ranged from 1.5 to 8.0 cm (mean 4.2 cm, median 4.3 cm). The basic architecture of the tumors was solid-alveolar in two cases (classified as renal cell carcinoma-not otherwise specified (NOS)) and papillary in seven cases (classified as papillary renal cell carcinoma NOS). The nuclear grade according to the Fuhrman grading system was three in all cases. By immunohistochemistry, the cells with microvacuolated cytopasm and significantly expressed adipophilin and anti-mitochondrial antigen in a similar cytoplasmic pattern. On ultrastructural examination, the cytoplasm of the neoplastic epithelial cells was packed with distended mitochondria, most of which displayed lamellated cristae. Numerous microvesicles were dispersed between the mitochondria. No mutations in the succinate dehydrogenase B gene were identified. Based on our findings, we propose that the mechanism behind this phenomenon is an abnormal intracellular processing of lipids. No aggressive behavior was observed in six out of nine patients with available follow-up information.
authors.affiliation: Department of Pathology, National University Health System, Singapore, Singapore.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Petersson
authors.forename: Maris
authors.initials: M
authors.lastname: Sperga
authors.forename: Stela
authors.initials: S
authors.lastname: Bulimbasic
authors.forename: Petr
authors.initials: P
authors.lastname: Martinek
authors.forename: Marian
authors.initials: M
authors.lastname: Svajdler
authors.forename: Naoto
authors.initials: N
authors.lastname: Kuroda
authors.forename: Milan
authors.initials: M
authors.lastname: Hora
authors.forename: Roderick
authors.initials: R
authors.lastname: Simpson
authors.forename: Tomáš
authors.initials: T
authors.lastname: Tichy
authors.forename: Kvetoslava
authors.initials: K
authors.lastname: Peckova
authors.forename: Jindrich
authors.initials: J
authors.lastname: Branzovsky
authors.forename: Kristyna
authors.initials: K
authors.lastname: Pivovarcikova
authors.forename: Pavla
authors.initials: P
authors.lastname: Rotterova
authors.forename: Bohuslava
authors.initials: B
authors.lastname: Kokoskova
authors.forename: Kevin
authors.initials: K
authors.lastname: Bauleth
authors.forename: Dusan
authors.initials: D
authors.lastname: Martincok
authors.forename: Vincent
authors.initials: V
authors.lastname: Nagy
authors.forename: Michal
authors.initials: M
authors.lastname: Michal
authors.forename: Ondrej
authors.initials: O
authors.lastname: Hes
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D002292:Carcinoma, Renal Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008067:Lipoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D008875:Middle Aged; D008928:Mitochondria / Q000473:pathology / Q000648:ultrastructure; D009154:Mutation / Q000235:genetics; D000070780:Perilipin-2; D013385:Succinate Dehydrogenase / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; D008565:Membrane Proteins; C000602982:PLIN2 protein, human; D000070780:Perilipin-2; C108095:SDHB protein, human; D013385:Succinate Dehydrogenase