Dual immunocytochemical staining of annexin A10 and p53 in low‐grade and papillary urothelial carcinoma contributes to improvement of diagnostic accuracy in urine cytology

Abstract Background Urothelial carcinoma (UC) is a common type of human cancer and, although urine cytology is a useful method for identifying high‐grade UC (HGUC), its ability to diagnose low‐grade UC (LGUC) is limited. The authors previously reported that annexin A10 (ANXA10) expression was strongly linked to both papillary and early stage LGUC and was inversely correlated with p53 expression in upper tract UC (UTUC) and bladder UC. However, it remains largely unknown whether ANXA10 is useful as a diagnostic marker for urine cytology. Methods In this study, the authors used 104 biopsy and 314 urine cytology samples to investigate the efficacy of ANXA10 and p53 expression by immunohistochemistry and immunocytochemistry. Results In immunohistochemistry analysis, expression levels of ANXA10 and p53 were either weak or absent in noncancerous tissues, whereas ANXA10 overexpression was observed patients with LGUC, and strong expression of p53 was identified in patients with HGUC. In immunocytochemistry analysis, sensitivity was not good for the detection of UC, especially UTUC, by cytology alone, but it was improved by combining cytology with ANXA10 and p53 to detect both bladder UC and UTUC. Receiver operating characteristic curve analysis also confirmed the diagnostic superiority of cytology combining ANXA10 and p53 for the detection of all UCs, including both HGUC and LGUC (area under the curve, 0.84). Conclusions To the authors’ knowledge, this is the first report that the combination of ANXA10 and p53 has potential application as a diagnostic immunomarker for improving the diagnostic accuracy of urine cytology.