TY - JOUR
T1 - LMP2, a novel immunohistochemical marker to distinguish renal oncocytoma from the eosinophilic variant of chromophobe renal cell carcinoma
AU - Zheng, Gang
AU - Chaux, Alcides
AU - Sharma, Rajni
AU - Netto, Georges J
AU - Caturegli, Patrizio
N1 - Funding Information:
The study was supported by NIH grant DK55670 to PC, and by the Joseph C. Eggleston research grant from the Johns Hopkins Department of Pathology to GZ.
PY - 2013/2
Y1 - 2013/2
N2 - LMP2 is a subunit of the immunoproteasome that is overexpressed in oncocytic lesions of the thyroid gland. This study was designed to assess the expression profile and diagnostic utility of LMP2 in two renal oncocytic tumors that share similar morphologic features but have different clinical outcomes: renal oncocytoma (RO) and the eosinophilic variant of chromophobe renal cell carcinoma (CHRCC-EO). A total of 56 RO, 38 classic CHRCC, and 7 CHRCC-EO cases, as well 84 normal kidney controls, were selected from the Johns Hopkins surgical pathology archive and stained for LMP2 using a standard immunohistochemical protocol. Sections were scored for cellular location (nuclear versus cytosolic), intensity (from 0 to 3), and percent of area involved (from 0 to 100%), and an H score was calculated multiplying the intensity by the extent of the staining signal. The cytoplasmic expression of LMP2 was similar among the renal lesions, being present in 44 of 56 (79%) ROs, 27 of 38 (71%) CHRCCs, and 7 of 7 (100%) CHRCC-EO cases. The nuclear expression of LMP2, however, was more informative. All CHRCC-EO cases (7 of 7, 100%) strongly showed nuclear LMP2 staining, as opposed to only 2 of 56 (4%, P < 0.0001) ROs and 9 of 38 (24%, P = 0.0001) classic CHRCCs. These results suggest that the nuclear LMP2 expression can be used in clinical scenarios where histological distinction between RO and CHRCC-EO remains challenging.
AB - LMP2 is a subunit of the immunoproteasome that is overexpressed in oncocytic lesions of the thyroid gland. This study was designed to assess the expression profile and diagnostic utility of LMP2 in two renal oncocytic tumors that share similar morphologic features but have different clinical outcomes: renal oncocytoma (RO) and the eosinophilic variant of chromophobe renal cell carcinoma (CHRCC-EO). A total of 56 RO, 38 classic CHRCC, and 7 CHRCC-EO cases, as well 84 normal kidney controls, were selected from the Johns Hopkins surgical pathology archive and stained for LMP2 using a standard immunohistochemical protocol. Sections were scored for cellular location (nuclear versus cytosolic), intensity (from 0 to 3), and percent of area involved (from 0 to 100%), and an H score was calculated multiplying the intensity by the extent of the staining signal. The cytoplasmic expression of LMP2 was similar among the renal lesions, being present in 44 of 56 (79%) ROs, 27 of 38 (71%) CHRCCs, and 7 of 7 (100%) CHRCC-EO cases. The nuclear expression of LMP2, however, was more informative. All CHRCC-EO cases (7 of 7, 100%) strongly showed nuclear LMP2 staining, as opposed to only 2 of 56 (4%, P < 0.0001) ROs and 9 of 38 (24%, P = 0.0001) classic CHRCCs. These results suggest that the nuclear LMP2 expression can be used in clinical scenarios where histological distinction between RO and CHRCC-EO remains challenging.
KW - Chromophobe renal cell carcinoma
KW - LMP2
KW - Renal oncocytomas
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U2 - 10.1016/j.yexmp.2012.05.008
DO - 10.1016/j.yexmp.2012.05.008
M3 - Article
C2 - 22705098
AN - SCOPUS:84870906656
SN - 0014-4800
VL - 94
SP - 29
EP - 32
JO - Experimental and Molecular Pathology
JF - Experimental and Molecular Pathology
IS - 1
ER -