原發性尿道鱗狀上皮癌 — 罕見病例報告與文獻回顧
郭炫廷、楊景偉、蔡昇翰、黃家倫、王曉暹、陳光國、張心湜 與 謝啟誠
振興醫療財團法人振興醫院泌尿部
Primary Urethral Squamous Cell Carcinoma - A Rare Case Report and Literature Review
Hsuan-Ting Kuo, Chin-Wei Yang, Sheng-Han Tsai, Chia-Lun Huang, Hsiao-Hsian Wang, Kuang-Kuo Chen, Luke S. Chang, and Chi-Cheng Hsieh
Department of Urology, Cheng Hsin General Hospital, Taipei, Taiwan
Introduction: Primary urethral cancers are uncommon condition in the malignancy of the whole urinary tract, and anterior urethral occurrence with squamous cell carcinoma (SCC) pathology is especially rare. We herein present a clinical case diagnosed of primary urethral SCC with regional lymph nodes metastasis who treated with cisplatin-based chemotherapy and achieved clinical complete response.
Presentation of case: A 63-year-old man called at our urology outpatient department with the complaint of a palpable penile mass noted for two months. He had ever visited local hospital for evaluation where tissue biopsy under urethroscopy turned out to be SCC. Physical examination a revealed palpable, non-tendered mass at penis and right inguinal enlarged lymph node. Sonography-guided right inguinal lymph node biopsy was done, and the pathology report suggested metastatic SCC. Urethroscopy was performed and revealed an anterior urethral mass occupying nearly whole lumen. Pelvis contrast CT scan for staging was arranged and showed a soft tissue mass at anterior penis with a enlarged right inguinal lymph node. To further study possible involvement of adjacent local structure, pelvis contrast MRI was ordered and showed anterior soft tissue mass with invasion to corpus spongiosum. The tentative clinical staging was cT2N1M0, stage III. Neo-adjuvant chemotherapy with paclitaxel, ifosfamide and cisplatin (TIP regimen) were administered for four cycles. Serial follow-up studies included pelvic CT scan three months later showed complete response radiographically without lymphadenopathy. Urethroscopy showed irregular mucosa at anterior urethra and re-biopsy showed chronic inflammation. Re-biopsy of the right inguinal lymph node was done and detected only benign fibroadipose tissue. Urethrectomy with lymph node dissection was suggested but the patient hesitated. Radiotherapy to right inguinal lymph node and anterior penis would be arranged in the future with close outpatient clinic follow-up.
Discussion: Primary urethral carcinoma accounts for less than 1% of all urinary tract malignancy. The most common histopathology type of primary urethral cancer is urothelial carcinoma (54-65%), followed by squamous cell carcinoma (16-22%) and adenocarcinoma (10-16%). The lining epithelium of male urethra is not the same according to different segments. The prostatic urethra and bulbomembranous urethra are covered with transitional epithelium, and most of penile urethra is covered with pseudostratified columnar epithelium. The meatus and the distal part of penile urethra, however, are covered with stratified squamous epithelium which can explain the pathology of SCC in anterior urethra. Thorough history taking with physical examination including external genitalia and bilateral inguinal lymph nodes are necessary. Diagnostic evaluation and staging approach according to EAU guideline recommendation including using cystourethroscopy with tumor biopsy and urine cytology to confirm cancer diagnosis, pelvic MRI for assessment of the disease local extent and regional lymphadenopathy, and abdominal CT scan to rule out distant metastasis. As for locally advanced urethral SCC, concurrent chemoradiotherapy with 5-fluorouracil and mitomycin C as a surgical alternative had been proposed. Nearly 80% of patient under the treatment can achieve complete clinical response, with a reported five-year overall survival up to 52% and disease-free survival up to 68%. In our case, we chose TIP regimen as inductive chemotherapy according to the rationale of penile SCC for locally advanced urethral SCC and achieved complete response after four cycles of treatment. Despite the patient is hesitated about consolidative surgery, radiotherapy may also be considered as an alternative treatment option.