Abstract
Urothelial carcinoma (UC) comprises a heterogeneous group of epithelial neoplasms with diverse biological behaviors and variable clinical outcomes. Distinguishing UC histological subtypes has become increasingly important because prognoses and therapy can dramatically differ among subtypes. In clinical work, overlapping morphological findings between low-grade noninvasive UC (LGNUC), which exhibits an inverted growth pattern, and inverted urothelial papilloma (IUP) can make subclassification difficult. We propose a combination of immunohistochemistry (IHC) and molecular cytogenetics for subtyping these clinical entities. In our study, tissue microarray immunohistochemical profiles of Ki-67, p53, cytokeratin 20 (CK20) and cyclinD1 were assessed. Molecular genetic alterations such as the gain of chromosomes 3, 7 or 17 or the homozygous loss of 9p21 were also assessed for their usefulness in differentiating these conditions. Based on our analysis, Ki-67 and CK20 may be useful for the differential diagnosis of these two tumor types. Fluorescence in situ hybridization (FISH) can also provide important data in cases in which the malignant nature of an inverted urothelial neoplasm is unclear. LGNUC with an inverted growth pattern that is negative for both Ki-67 and CK20 can be positively detected using FISH.
Highlights
Because of their diverse histological features, urothelial carcinomas (UCs) can be classified into a number of different morphological and architectural patterns [1,2,3,4,5]
When only a small amount of biopsy material is available or when transurethral resections are examined, there is great overlap microscopically between low-grade noninvasive UC (LGNUC) with an inverted growth pattern and inverted urothelial papilloma (IUP), which is a rare benign tumor that accounts for approximately 1% to 2% of all urothelial neoplasms[6, 7]; discriminating between these cases is problematic
Of the 36 inverted papillomas, peripheral palisading nuclei were observed in 31 cases (86.1%), and streaming in the inferior of cords or nests was observed in 28 cases (77.8%)
Summary
Because of their diverse histological features, urothelial carcinomas (UCs) can be classified into a number of different morphological and architectural patterns [1,2,3,4,5]. LGNUC and IUP Can Be Distinguished by IHC and FISH an inverted or endophytic growth pattern. Whether to designate lesions as IUP or as LGNUC with an inverted growth pattern is important because their biological behaviors, subsequent treatments and prognoses differ. We used various techniques, including immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) to determine the intrinsic differences between these two lesions and to correlate the findings with the need for a differential diagnosis
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
