Urethral anatomy

Primary carcinoma of urethra + urothelial carcinoma of prostate

• Epithelium of urethra transitions from stratified squamous to pseudostratified columnar to urothelium (transitions in membranous urethra); cancer will be SCC in urethra distal to membranous, and adenocarcinoma proximal to membranous

Benign urethral lesions

• In women: urethral caruncle, diverticulum, Skene's gland cyst
• Urethral condyloma - observation OK for small lesions.
  • Multimodal treatment - intraurethral 5-FU +/- holmium laser ablation.
  • 5-FU in jelly- qweek x 6wk, 6 wk hiatus, then repeat 6-week cycle
• Leiomyoma - most common in reproductive age women; can grow during pregnancy and regress postpartum
• Hemangioma - more common in men; bluish sessile lesion
• Fibroepithelial polyp - more common in men; smooth pink/tan tumors on a stalk

• Inguinal node exam for urethral ca (LN drainage of anterior/distal urethra -> inguinal nodes; proximal/posterior urethra -> external iliac and pelvic nodes)
  • Unlike penile cancer, no survival benefit for ILND for urethral cancer if clinically N0, even if T3 disease.

Urethrectomy anatomy

Urethral blood supply

• Blood supply: internal iliac/hypogastric → internal pudendal → common penile → cavernosal, bulbar/urethral, deep dorsal (spongiosum).
  • To anterior urethra, primary supplies are bulbar/urethral arteries; deep dorsal also contributes via retrograde flow through glans anastomoses arteries if the spongiosum/artery is transected (but circumflex arteries will be disrupted). 

Picture - Wiki - perineal hernia

• Chest XR or CT
• MRI pelvis with/without contrast

Urethral cancer

• < T2 - TUR +/- intraurethral chemotherapy or BCG
• T2 female - chemo/XRT vs cystectomy+urethrectomy vs distal urethrectomy. 
  • Recurrence - systemic therapy vs chemo/XRT vs pelvic exent
• T2 male
  • Fossa/penile urethra - treat with distal urethrectomy vs partial penectomy.
    • - margins: survey
    • + margins: chemo/XRT (preferred) vs surgery vs XRT
    • Recurrence: systemic therapy +/- total penectomy +/- XRT
  • Bulbar/membranous urethra - urethrectomy +/- cystoprostatectomy
    • pT1/pT2 and N0 - surveil with cystoscopy
    • pT3+ or N+ - consider chemo +/- XRT
    • Recurrence: systemic therapy +/- XRT
• T3-T4N0 - chemo +/- consolidative surgery; XRT alone
  • If UC - also consider NAC + consolidative surgery or radiation
  • If non-UC - also consider surgery alone
• Node positive - chemo/XRT +/- consolidative surgery. SCC - prefer chemo/XRT.
• Metastatic disease - include brain in staging imaging; molecular testing for FGFR alterations; systemic tx with gem/cis or DD-MVAC

Urothelial carcinoma of prostate

• Ta/Tis - TURP + BCG
  • Recurrence: cystoprostatectomy +/- urethrectomy
• T1 (ductal) - RC +/- urethrectomy vs TURP + BCG
• T2 (stromal) - +/- neoadjuvant or adjuvant chemo; RC +/- urethrectomy