Yu Yang1, Hristos Z Kaimakliotis2, Sean R Williamson3, Michael O Koch2, Kun Huang4, Marcelo P Barboza2, Shaobo Zhang1, Mingsheng Wang1, Muhammad T Idrees1, David J Grignon1, John N Eble1, Lee Ann Baldridge1, Liang Cheng5. 1. Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN. 2. Department of Urology, Indiana University School of Medicine, Indianapolis, IN. 3. Department of Pathology and Laboratory Medicine and Henry Ford Cancer Institute, Henry Ford Health System, Detroit, MI; Department of Pathology and Laboratory Medicine, Wayne State University School of Medicine, Detroit, MI. 4. Department of Medicine, Indiana University School of Medicine, Indianapolis, IN. 5. Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN; Department of Urology, Indiana University School of Medicine, Indianapolis, IN. Electronic address: liang_cheng@yahoo.com.
Abstract
OBJECTIVES: Micropapillary urothelial carcinoma of the urinary bladder (MPUC) is a rare variant of urothelial carcinoma which has aggressive clinical characteristics. The objective is to investigate the molecular subtypes of MPUC and the impact to the clinical outcome and determine whether MPUC represents a variant of adenocarcinoma. MATERIALS AND METHODS: We evaluated surrogate immunohistochemical markers of luminal, basal, and p53-like subtypes and correlated with prognosis and the expression of markers related to bladder adenocarcinoma and glandular differentiation in 56 cases of MPUC (10 cases of transurethral resection and 46 cases of radical cystectomy). Biomarker expression in co-existing conventional urothelial carcinoma was also analyzed. Cox regression analysis was performed to study the impact of molecular subtype on the clinical outcome. RESULTS: Thirty-four cases (61%) met criteria for the luminal subtype. Twenty-two cases (39%) displayed a p53-like subtype. In contrast, 40/56 (71%) cases of coexisting conventional urothelial carcinoma were classified as luminal subtype and 16/56 (29%) cases were designated as p53-like subtype. There was no significant survival difference between luminal subtype and p53-like subtype. CDX2, villin, and cadherin 17 were negative in all cases. MUC1 was strongly and diffusely expressed in the stroma-facing surface of MPUC tumor cells in all the cases. CONCLUSIONS: Our findings suggest that MPUC possesses characteristics of luminal and p53-like subtypes, and does not harbor phenotypic features of the basal subtype. There is no significant difference in the prognosis between luminal and p53-like subtype MPUC. MPUC is not a variant of adenocarcinoma and does not represent a form of glandular differentiation, in contrast to other organ sites.
OBJECTIVES:Micropapillary urothelial carcinoma of the urinary bladder (MPUC) is a rare variant of urothelial carcinoma which has aggressive clinical characteristics. The objective is to investigate the molecular subtypes of MPUC and the impact to the clinical outcome and determine whether MPUC represents a variant of adenocarcinoma. MATERIALS AND METHODS: We evaluated surrogate immunohistochemical markers of luminal, basal, and p53-like subtypes and correlated with prognosis and the expression of markers related to bladder adenocarcinoma and glandular differentiation in 56 cases of MPUC (10 cases of transurethral resection and 46 cases of radical cystectomy). Biomarker expression in co-existing conventional urothelial carcinoma was also analyzed. Cox regression analysis was performed to study the impact of molecular subtype on the clinical outcome. RESULTS: Thirty-four cases (61%) met criteria for the luminal subtype. Twenty-two cases (39%) displayed a p53-like subtype. In contrast, 40/56 (71%) cases of coexisting conventional urothelial carcinoma were classified as luminal subtype and 16/56 (29%) cases were designated as p53-like subtype. There was no significant survival difference between luminal subtype and p53-like subtype. CDX2, villin, and cadherin 17 were negative in all cases. MUC1 was strongly and diffusely expressed in the stroma-facing surface of MPUC tumor cells in all the cases. CONCLUSIONS: Our findings suggest that MPUC possesses characteristics of luminal and p53-like subtypes, and does not harbor phenotypic features of the basal subtype. There is no significant difference in the prognosis between luminal and p53-like subtype MPUC. MPUC is not a variant of adenocarcinoma and does not represent a form of glandular differentiation, in contrast to other organ sites.
Authors: Ewan A Gibb; Joaquim Bellmunt; Joep J de Jong; Begoña P Valderrama; Julia Perera; Nuria Juanpere; Paloma Cejas; Henry Long; M Mar Albà Journal: Br J Cancer Date: 2022-04-21 Impact factor: 9.075