Cathepsin H expression distinguishes oncocytomas from renal cell carcinomas.
BACKGROUND
Because the differential diagnosis of oncocytoma and renal cell carcinoma lacks specificity, new methods supporting correct diagnostic decisions are welcome.


METHODS
Sixteen cases of renal oncocytoma, and 16 sex-, age-, and stage- matched controls of renal cell carcinoma (T1-2N0M0) were studied. The minimum follow up exceeded ten years. There were no deaths due to neoplasm among oncocytomas, but 4 patient died with metastatic disease among cancer patients. Immunohistochemical staining for cathepsin H was quantified by 3 histoscores. The histoscores evaluated: 1) even cytoplasmic staining of neoplastic cells, 2) granular staining, or 3) total staining.


RESULTS
100% distinction was possible with the even cytoplasmic staining score. Total staining distinguished 87.5%, and granular staining 25% of neoplasms. CAM 5.2 cytokeratin, or vimentin distinguished 84.4% or 56.6% of these tumors, respectively.


CONCLUSIONS
Cathepsin H histoscore on even cytoplasmic immunostaining is an excellent method for the distinction of oncocytomas and renal cell carcinomas.
Castrén
J P
JP
Department of Pathology, University of Turku, Finland. janne.castren.utu.fi
Kamel
D E
DE
Nurmi
M J
MJ
Collan
Y U
YU
D018249:Adenoma, Oxyphilic / Q000175:diagnosis / Q000201:enzymology* / Q000401:mortality / Q000473:pathology; D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis*; D002292:Carcinoma, Renal Cell / Q000175:diagnosis / Q000201:enzymology* / Q000401:mortality / Q000473:pathology; D016022:Case-Control Studies; D056655:Cathepsin H; D002403:Cathepsins / Q000032:analysis*; D003546:Cysteine Endopeptidases / Q000032:analysis*; D003937:Diagnosis, Differential; D004790:Enzyme Induction; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis / Q000201:enzymology* / Q000401:mortality / Q000473:pathology; D008297:Male; D009362:Neoplasm Metastasis; D009363:Neoplasm Proteins / Q000032:analysis*; D009392:Nephrectomy; D011379:Prognosis; D012189:Retrospective Studies
D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D002403:Cathepsins; D003546:Cysteine Endopeptidases; C534126:CTSH protein, human; D056655:Cathepsin H