Lymphoepithelioma-like carcinoma of the urinary bladder: a clinicopathologic study of 13 cases

Abstract

Lymphoepithelioma-like carcinoma (LELCA) of the urinary bladder is a rare variant of bladder cancer characterized by a malignant epithelial component densely infiltrated by lymphoid cells. It is characterized by indistinct cytoplasmic borders and a syncytial growth pattern. These neoplasms deserve recognition and attention, chiefly because they may be responsive to chemotherapy. We report on the clinicopathologic features of 13 cases of LELCA recorded since 1981. The chief complaint in all 13 patients was hematuria. Their ages ranged from 58 years to 82 years. All tumors were muscle invasive. A significant lymphocytic reaction was present in all of these tumors. There were three pure LELCA and six predominant LELCA with a concurrent transitional cell carcinoma (TCC). The remainder four cases had a focal LELCA component admixed with TCC. Immunohistochemistry showed LELCA to be reactive against epithelial membrane antigen and several cytokeratins (CKs; AE1/AE3, AE1, AE3, CK7, and CK8). CK20 and CD44v6 stained focally. The lymphocytic component was composed of a mixture of T and B cells intermingled with some dendritic cells and histiocytes. Latent membrane protein 1 (LMP1) immunostaining and in situ hybridization for Epstein-Barr virus were negative in all 13 cases. DNA ploidy of these tumors gave DNA histograms with diploid peaks (n=7) or non-diploid peaks (aneuploid or tetraploid; n=6). All patients with pure and 66% with predominant LELCA were alive, while all patients having focal LELCA died of disease. Our data suggest that pure and predominant LELCA of the bladder appear to be morphologically and clinically different from other bladder (undifferentiated and poorly differentiated conventional TCC) carcinomas and should be recognized as separate clinicopathological variants of TCC with heavy lymphocytic reaction relevant in patient management.

Lymphoepithelioma-like carcinoma of the urinary bladder: report of a rare case

“…The largest study was reported by Tamas et al8 who described 17 pure 13 mixed LELC. Prior to that Lopez-Beltran et al5 reported 3 pure, 6 predominant and 4 focal LELCs of the urinary bladder. Amin et al3 reported 3 pure, 5 predominant and 3 focal LELCs and Holmang et al6 described 3 pure, 5 predominant and 3 focal cases of LELC.…”

“…It has been suggested that abnormalities of p53 regulation might be crucial in the pathogenesis of LELC of the urinary bladder 10. Though the exact origin of these carcinomas is not well known, the expression of common urothelial markers suggest that they are probably modified urothelial cells that have derived from stem cells 56…”

“…Most patients present with painless hematuria and are stage T2-T3 at diagnosis 568. Histological features of LELC closely resemble lymphoepithelioma of the nasopharynx, with the tumor growing in nests, sheets or cords of large undifferentiated malignant epithelial cells within a dense inflammatory background, comprising mature lymphocytes, plasma cells, and rarely neutrophils and eosinophils.…”

“…Amin et al3 categorized the LELC of bladder into three subgroups as pure, predominant (more than 50% lymphoepithelial component) and focal (less than 50% lymphoepithelial component). Invasive urothelial carcinoma usually accompanies predominant or focal LELC 358. Though uncommon, the tumor may have accompanying adenocarcinoma and squamous cell carcinoma as well 58.…”

“…The tumor can occur either in pure form or in association With conventional urothelial carcinoma 3. The pure form is considered to have a better prognosis and exhibits a good response to chemotherapy 2–5. It is important to differentiate LELC from non-Hodgkin lymphoma, poorly differentiated invasive transitional cell carcinoma and poorly differentiated squamous cell carcinoma with lymphoplasmacytic infiltrate in the background.…”