Cytokeratin 20 immunoreactivity in renal oncocytomas.

TY - JOUR

T1 - Cytokeratin 20 immunoreactivity in renal oncocytomas.

AU - Stopyra, G A

AU - Warhol, M J

AU - Multhaupt, H A

N1 - Keywords: Adenoma, Oxyphilic; Humans; Immunohistochemistry; Intermediate Filament Proteins; Keratin-20; Keratin-7; Keratins; Kidney Neoplasms; Tumor Markers, Biological

PY - 2001

Y1 - 2001

N2 - Cytokeratins (CKs) are a group of 20 antigenically distinct intermediate filaments, generally confined to epithelia and their neoplasms. Immunostaining for CKs, in particular coordinate staining for CK7 and CK20, has become a useful tool in diagnostic pathology. Although studies defining CK distribution in neoplasms identify 0--7.7% of renal cell carcinomas (RCCs) positive for CK20, none has described the incidence of CK20 immunopositivity in renal oncocytomas (ROs). Distinction between RCC and RO may be difficult but this distinction is clinically significant, prompting us to establish the incidence of CK20 positivity in RO. We selected fifteen surgical cases of RO from our archives and studied their immunoreactivity for CKs including CK7 and CK20; 12/15 (80%) were positive for CK20, with variation in the number of cells staining. There was also variation in the distribution of CKs within the cells, including diffuse cytoplasmic, perinuclear, and a punctate or dot-like pattern. Such punctate staining corresponds to cytoplasmic balls of intermediate filaments and has been described with CAM 5.2 in RO and CK20 in Merkel cell carcinomas. Our findings suggest that CK20 immunohistochemistry is a useful tool for distinguishing RCCs from ROs. (J Histochem Cytochem 49:919-920, 2001)

AB - Cytokeratins (CKs) are a group of 20 antigenically distinct intermediate filaments, generally confined to epithelia and their neoplasms. Immunostaining for CKs, in particular coordinate staining for CK7 and CK20, has become a useful tool in diagnostic pathology. Although studies defining CK distribution in neoplasms identify 0--7.7% of renal cell carcinomas (RCCs) positive for CK20, none has described the incidence of CK20 immunopositivity in renal oncocytomas (ROs). Distinction between RCC and RO may be difficult but this distinction is clinically significant, prompting us to establish the incidence of CK20 positivity in RO. We selected fifteen surgical cases of RO from our archives and studied their immunoreactivity for CKs including CK7 and CK20; 12/15 (80%) were positive for CK20, with variation in the number of cells staining. There was also variation in the distribution of CKs within the cells, including diffuse cytoplasmic, perinuclear, and a punctate or dot-like pattern. Such punctate staining corresponds to cytoplasmic balls of intermediate filaments and has been described with CAM 5.2 in RO and CK20 in Merkel cell carcinomas. Our findings suggest that CK20 immunohistochemistry is a useful tool for distinguishing RCCs from ROs. (J Histochem Cytochem 49:919-920, 2001)

M3 - Journal article

C2 - 11410616

SN - 0022-1554

VL - 49

SP - 919

EP - 920

JO - Journal of Histochemistry and Cytochemistry

JF - Journal of Histochemistry and Cytochemistry

IS - 7

ER -