Oberc Alexander M, Sherman Christopher, Downes Michelle R
Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Canada.
Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada.
Int J Surg Pathol. 2025 May;33(3):656-660. doi: 10.1177/10668969241286069. Epub 2024 Oct 3.
Urethral strictures are a common cause of urinary obstruction which can be treated with surgical resection. Frozen sections are rare and pose a diagnostic challenge to pathologists due to the presence of benign lesions such as nephrogenic adenoma. We retrospectively examined all specimens of urethral stricture resections submitted to pathology at our institution from 2012 to 2022 (n = 258). Final pathology reports were searched to identify patients with dysplasia, carcinoma, or nephrogenic adenoma. When available, frozen section reports were also examined and compared to the final report, and additional clinical history and microscopic images were collected for patients with nephrogenic adenoma. Nephrogenic adenoma was identified in 3.8% (10/258) of urethral stricture resections. Dysplasia was identified in one patient who underwent two separate resections, and squamous cell carcinoma was found in one resection. Intraoperative frozen section was requested in 3.4% of resections (9/258). In two resections, an initial diagnosis of squamous cell carcinoma was initially favoured, however when reviewed with a genitourinary pathologist the diagnosis was changed to "reactive process" with a final diagnosis of nephrogenic adenoma. Nephrogenic adenoma can be challenging on frozen section due to variable architectural patterns, inflammation, and reactive changes. While urethral strictures are relatively common, their assessment by frozen section is rare and pathologists may lack familiarity with the variable morphology of benign entities that can be seen on frozen section resulting in their misinterpretation. We highlight this potential diagnostic pitfall and demonstrate the value of a second opinion prior to definitive frozen section diagnosis of malignancy.
尿道狭窄是尿路梗阻的常见原因，可通过手术切除进行治疗。由于存在诸如肾源性腺瘤等良性病变，冰冻切片很少见，对病理学家构成诊断挑战。我们回顾性研究了2012年至2022年在我们机构提交病理检查的所有尿道狭窄切除术标本（n = 258）。检索最终病理报告以确定发育异常、癌或肾源性腺瘤患者。如有可用的冰冻切片报告，也进行检查并与最终报告进行比较，并为肾源性腺瘤患者收集额外的临床病史和显微图像。在3.8%（10/258）的尿道狭窄切除术中发现了肾源性腺瘤。在一名接受两次单独切除的患者中发现了发育异常，在一次切除中发现了鳞状细胞癌。3.4%（9/258）的切除术要求进行术中冰冻切片。在两次切除术中，最初倾向于诊断为鳞状细胞癌，但在与泌尿生殖病理学家会诊时，诊断改为“反应性过程”，最终诊断为肾源性腺瘤。由于结构模式、炎症和反应性变化的不同，肾源性腺瘤在冰冻切片上可能具有挑战性。虽然尿道狭窄相对常见，但通过冰冻切片对其进行评估很少见，病理学家可能不熟悉在冰冻切片上可见的良性实体的可变形态，从而导致对其错误解读。我们强调了这一潜在的诊断陷阱，并展示了在对恶性肿瘤进行明确的冰冻切片诊断之前寻求第二种意见的价值。
