Pathological Approach to Genitourinary System Premalignant Lesions: Case Presentations from Clinical and Histological Perspectives

Year 2025, Volume: 11 Issue: 4, 428 - 440, 30.11.2025

Havva Erdem , Mürüvvet Akçay Çelik , Meltem Türk Alkan , Beyza Bıyıklı , Büşra Erşan Erdem

https://doi.org/10.19127/mbsjohs.1745573

Abstract

Genitourinary system malignancies comprise a group of neoplasms that form the foundation of urological oncology and include some of the most common cancers in men. Within this group, prostate, bladder, kidney, and testicular cancers stand out due to their high incidence and varying characteristics in terms of histogenesis, molecular pathogenesis, and clinical behavior. In recent years, there has been growing interest in the identification and characterization of premalignant lesions, which are now recognized as histological precursors to invasive carcinomas. These lesions allow for early diagnosis and the development of targeted surveillance strategies. In this article, we present six cases diagnosed in our clinic, each representing a different type of premalignant lesion in the genitourinary system. The lesions include urothelial dysplasia, carcinoma in situ (CIS), keratinizing squamous metaplasia (KSM), and urothelial proliferation of unknown malignant potential (UPUMP) in the bladder; prostatic intraepithelial neoplasia (PIN), atypical small acinar proliferation (ASAP), and atypical adenomatous hyperplasia (AAH) in the prostate; and germ cell neoplasia in situ (GCNIS) in the testis. Premalignant lesions are histopathological changes that can be identified prior to the development of invasive malignancies, each carrying a different risk of progression. Accurate identification, knowledge of their morphological criteria, and support with immunohistochemical methods when necessary are critical in the diagnostic process. The cases presented in this study demonstrate the histopathological and clinical diversity of these lesions and offer guidance for diagnostic approaches. Early diagnosis of premalignant lesions in the genitourinary system is essential for preventing the development of invasive malignancies. Proper histopathological identification of these lesions enables appropriate clinical management and follow-up. The presented cases highlight the diagnostic features of various premalignant entities and emphasize the importance of multidisciplinary collaboration. Accurate recognition of these lesions by pathologists forms the cornerstone of early intervention and cancer prevention.

Keywords

Premalignant lesions , Genitourinary system , Dysplasia , Carcinoma in situ , Germ cell neoplasia in situ , Prostatic intraepithelial neoplasia

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