Ezrin immunoreactivity in renal cell carcinomas.

OBJECTIVE To determine ezrin's association with clinicopathologic features and to investigate the possible effects of the presence of ezrin on the differential diagnosis of subtypes of renal cell carcinoma (RCC). STUDY DESIGN Ezrin reactivity was examined immunohistochemically in tumor tissues obtained from 78 patients who underwent radical nephrectomy for renal cell carcinoma. Correlation between ezrin expression and RCC subtypes was investigated and compared with tumor stage, grade and other clinicopathologic parameters. RESULTS There was no correlation between ezrin expression and clinicopathologic features. Furthermore, a significant correlation was found between ezrin reactivity and subtypes of RCC (p = 0.002). Ezrin reactivity was observed mainly in conventional, papillary and mucinous tubular spindle cell carcinoma (MTSCC) subtypes of RCC, while none of the chromophobe RCC was positive for ezrin. Sarcomatoid and unclassified subtypes of RCC were found to be faint and/or negative for ezrin reactivity. CONCLUSION Investigation of ezrin reactivity may be beneficial as an additional diagnostic marker in the differential diagnosis of RCC subtypes. Also, it seems to be useful to designate the origin of MTSCC.