title: Sporadic renal hemangioblastoma with CA9, PAX2 and PAX8 expression: diagnostic pitfall in the differential diagnosis from clear cell renal cell carcinoma.
abstract: To date, 13 cases of sporadic renal hemangioblastoma have been reported. In this article, we report such a case that might cause the diagnostic pitfall. A 37-year-old Japanese was found to have a renal mass by periodic medical check-up. He underwent radical nephrectomy. Macroscopically, the tumor was well-defined without fibrous capsule and the cut surface of the tumor exhibited light brown to gray-tan color without hemorrhage or necrosis. Microscopically, the tumor was made up of large polygonal to short spindle cells with eosinophilic cytoplasm with occasional vacuolization and abundant arborizing capillary network. Immunohistochemically, neoplastic cells showed diffuse positivity for inhibin-alpha, S-100 protein, vimentin, CA9, PAX2 and PAX8, but negativity for cytokeratin CAM5.2, alpha smooth muscle actin, Melanosome, Melan A, TFE3 and cathepsin K. In genetic analyses, this tumor showed no changes of VHL gene mutation, hypermethylation and loss of heterozygosity of chromosome 3p. Additionally, G-band karyotype and array comparative genomic hybridization studies showed a normal chromosome. In conclusion, the positivity for CA9, PAX2 and PAX8 in sporadic renal hemangioblastoma may cause the critical diagnostic pitfall in the differential diagnosis from clear cell renal cell carcinoma. Pathologists need to pay attention to systemic evaluation including macroscopic, microscopic and immunohistochemical findings. In some cases, molecular genetic study may be necessary.
authors.affiliation: Department of Pathology, Kochi Red Cross Hospital Kochi, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Kuroda
authors.affiliation: Department of Pathology, Kochi Red Cross Hospital Kochi, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Agatsuma
authors.affiliation: Department of Urology, Kochi Red Cross Hospital Kochi, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Tamura
authors.affiliation: Department of Pathology, Charles University in Prague, Faculty of Medicine in Plzen Plzen, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Martinek
authors.affiliation: Department of Pathology, Charles University in Prague, Faculty of Medicine in Plzen Plzen, Czech Republic.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Hes
authors.affiliation: Department of Pathology, Charles University in Prague, Faculty of Medicine in Plzen Plzen, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Michal
mesh_terms: D000328:Adult; D000951:Antigens, Neoplasm / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases / Q000378:metabolism*; D002292:Carcinoma, Renal Cell / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D003937:Diagnosis, Differential; D018325:Hemangioblastoma / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D008297:Male; D051762:PAX2 Transcription Factor / Q000378:metabolism*; D000072636:PAX8 Transcription Factor; D051761:Paired Box Transcription Factors / Q000378:metabolism*
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D051762:PAX2 Transcription Factor; C497318:PAX2 protein, human; D000072636:PAX8 Transcription Factor; C083325:PAX8 protein, human; D051761:Paired Box Transcription Factors; C089226:CA9 protein, human; D000071231:Carbonic Anhydrase IX; D002256:Carbonic Anhydrases
keywords: CA9; Hemangioblastoma; PAX2; PAX8; kidney