Primary urethral clear cell carcinoma: a rare case report.

A 59-year-old female patient was admitted due to a vaginal mass detected one month ago. There is no family history of malignant tumors, nor any relevant complications. One month prior, she incidentally palpated a cystic mass on the anterior vaginal wall while bathing. She reported no dysuria, hematuria, abdominal pain, or vaginal bleeding. Over the past week, she developed dysuria with interrupted urine flow, but no frequency or urgency. Pelvic MRI revealed a cystic-solid mass in the anterior vaginal wall with indistinct borders from the urethra. Needle biopsy of the vaginal mass combined with immunohistochemistry initially suggested clear cell adenocarcinoma. Final diagnosis was confirmed as primary urethral clear cell carcinoma by pathological examination of the radical resection specimen. Cystic masses in the anterior vaginal wall should raise suspicion for urothelial origin clear cell carcinoma. Fine-needle aspiration biopsy combined with immunohistochemistry may still yield misdiagnosis; definitive diagnosis relies on pathological examination of resected specimens.