Primary Clear Cell Adenocarcinoma of the Urethra: A Clinicopathologic Study of 16 Cases
Priya Rao, Bogdan A Czerniak, Charles C Guo. The University of Texas MD Anderson Cancer Center, Houston, TX
Background: Primary clear cell adenocarcinoma of the urethra is a rare neoplasm. Limited clinicopathologic data are available for this distinct tumor.
Design: We retrospectively searched our pathology database from 1987 to 2011 and found 16 cases of primary urethral clear cell adenocarcinoma. None of the patients had a previous history of vaginal carcinoma. The pathology specimens included biopsy (n=7) and resection specimens (n=9), and histologic and immunohistochemical slides were reviewed. Clinical information was collected from patients' medical records.
Results: All but one of the patients were women. The mean age at diagnosis was 63 years (range, 46–71 years). Hematuria was the most common presenting symptom (n=7). In 8 cases, the tumor arose within a urethral diverticulum. Histologically, the tumors showed tubular, papillary, nested, or hobnail growth patterns. The tumor cells were characterized by high-grade nuclear atypia and clear or slightly eosinophilic cytoplasm. Of the 5 cases for which immunohistochemical stains were available, all were strongly positive for CK7 and negative for CK20. Tumor stage was available for 11 patients based on pathologic and clinical examinations and revealed that the tumors invaded the muscularis propria (T2, n=3), periurethral adipose tissue and anterior vaginal wall (T3, n=6), or adjacent organs (T4, n=2). Six patients developed metastasis, to regional lymph nodes (n=4), bone (n=1), or liver (n=1). Follow-up information was available for 13 patients: 5 were free of disease at a mean of 31 months 2 were alive with disease after 10 and 16 months, respectively; 4 died of disease in a mean of 14 months; and 2 died of unrelated causes.
Conclusions: Primary clear cell adenocarcinoma of the urethra is a rare tumor with a strong predilection for women. The tumor often arises within a urethral diverticulum and presents as a deeply invasive lesion. Recognizing this tumor in small biopsy specimens may be challenging, and secondary involvement of the urethra by a vaginal primary should be clinically excluded.
Category: Genitourinary (including renal tumors)
Wednesday, March 21, 2012 1:00 PM
Poster Session VI # 155, Wednesday Afternoon