Urethral Cancer Flashcards
What percentage of urethral cancers are urothelial in origin?
A recent SEER (2004 to 2016) analysis demonstrated that
52.9% of primary urethral carcinomas are of urothelial origin
SCC (23.9% of cases)
Adenocarcinoma (14.6%)
Other histologies (8.7%)
Risk factors for urethral cancer
History of urothelial cancer, with recurrence rate in urethra of 4.9%
Sexually transmitted disease
Urethritis
Urethral stricture disease
Human papilloma virus (particularly subtypes 16 & 18)
Smoking
Symptoms of Urethral Cancer
Urethral cancer is frequently symptomatic at presentation in both men and women (~95%)
Common symptoms:
Irritative or obstructive voiding
Hematuria
Primary urethral bleeding
Additionally, especially in women, masses may be palpable and cause pain. The rare presentations of urethral carcinoma within urethral diverticula typically present with dyspareunia, dysuria, dribbling (the 3 D’s of urethral diverticulum). Solid components within a diverticulum can raise suspicion of concomitant malignancy and prompt biopsy.
T stage
Tis
Female urethra or male anterior urethra
Male posterior urethra
-Carcinoma in situ
-Prostatic urethra or periurethral or prostatic ducts without stromal invasion
Ta - Non-invasive papillary or verrucous carcinoma
T1 - Invades lamina propria (subepithelial connective tissue)
T2
Female urethra or male anterior urethra
Male posterior urethra
-invades corpus spongiosum, or periurethral muscle
-invades prostatic stroma (either by ducts or direct extension)
T3
Female urethra or male anterior urethra
Male posterior urethra
-invades corpus cavernosum or anterior vagina
-invades periprostatic fat
T4 - Invades adjacent organs (bladder, rectum, uterus)
N stage
N0 - Negative nodes
N1 - Single Node
N2 - Multiple Nodes
M stage
M0 - No metastases
M1 - Distant metastases
What can you tell about the T stage from a physical exam?
On physical examination of the male, the penis and perineum should be carefully palpated.
-Presence of a palpable mass usually indicates an invasive tumor (≥T2) and occasionally clear invasion of the corpora cavernosa is palpable (T3).
-DRE should be performed to evaluate for palpable prostatic invasion.
In women, a bimanual examination and careful speculum examination are required.
-A urethral diverticulum may be palpable and vaginal invasion is usually easily detectable (T3).
In both men and women, palpation of the inguinal nodes should be performed to rule out nodal involvement.
-Lymphedema of the lower extremities may point to inguinal or pelvic nodal involvement.
What workup should you do for urethral cancer?
Cystoscopy with look into a urethral diverticulum
Consider transvaginal needle biopsy
RUG in men
Ultrasound of the penis (MRI is preferred)
Abdominal-pelvic-inguinal imaging (CT, MRI, PET) - Contrast-enhanced MRI provides the best resolution images of the urethra and is favored over CT in most circumstances. Pelvic MRI (including the inguinal region/mid-upper thigh) is the preferred imaging modality to assess the local extent of the urethral tumor and regional lymph node involvement.
What percentage of men with urethral cancer have associated urethral strictures?
50%
Treatment of Squamous Cell Carcinoma of the Urethra
Patients with squamous cell carcinoma can be treated with either chemo-radiation or neoadjuvant chemotherapy followed by surgical consolidation.
Triple therapy (chemoradiation therapy followed by surgery) is sometimes used for bulky yet localized urethral cancer with direct extension into the pubis or genitourinary diaphragm
TUR for urethral cancer
TUR is the treatment of choice for all small non-invasive tumors of the distal urethra.
Additionally, TUR is the primary method used to stage and treat prostatic urethral and ductal cancer, obtain tissue for histology, and relieve urethral obstruction.
In patients with a history of NMIBC with normal cystoscopy and positive cytology, a clinician should consider prostatic urethral biopsies since tumor recurrences can involve the prostatic urethra in 24-39% of cases.
Such biopsies are normally done at the 5 and 7 o’clock positions to ensure sampling of the prostatic ducts.
If prostate urethral cancer (non invasive or CIS) is found after TUR …
For cases of non-invasive prostatic urethral carcinoma or carcinoma in situ, mucosal tumors, located in the prostatic urethra,
a TUR of the prostate (including the bladder neck to allow contact of intravesical agents to the posterior urethra/prostatic urethra) is followed by adjuvant intravesical BCG with maintenance therapy
Prostatic duct involvement is often seen with carcinoma in situ of the prostatic urethra (confined to the urothelium of the prostatic duct).
Based on small retrospective series CIS of the prostatic ducts may be treated with TUR followed by intravesical BCG with caution as there is high risk of progression, and patients may benefit from radical therapy.
In patients with urothelial carcinoma of the prostatic urethra with prostate stromal invasion, neoadjuvant cisplatin-based chemotherapy followed by radical cystoprostatectomy is the treatment of choice.
In patients with urothelial carcinoma of the prostatic urethra with prostate stromal invasion
In patients with urothelial carcinoma of the prostatic urethra with prostate stromal invasion, neoadjuvant cisplatin-based chemotherapy followed by radical cystoprostatectomy is the treatment of choice.
Penectomy in Urethral Cancers
If T2 (just spongiosum), can do a segmental urethrectomy.
If T3 (involving cavernosum), perform partial or radical penectomy. If radical penectomy, perineal urethrostomy.
Total Penectomy with Prostatectomy and Bladder Neck Closure
Bulky adenocarcinomas or squamous cell carcinomas of the bulbar and membranous urethra can be very challenging to manage.
Often, after resection, there is not enough urethral length to allow a perineal urethrostomy or there is no remaining urinary sphincter to allow for continence. Additionally, the prostate may be involved and require resection.
In this situation, one can consider bladder neck closure and either an incontinent ileal vesicostomy or Mitrofanoff-type channel.
NB: This is contraindicated in urothelial carcinomas given the risk of local recurrence within bladder and need for ongoing cystoscopic surveillance which is challenging to perform through either an ileal chimney or catheterizable channel.
When to do a cystoprostatectomy in urethral cancer
Invasive urothelial carcinomas of the prostatic/membranous urethra are usually best treated with radical cystoprostatectomy with total urethrectomy.
Neoadjuvant or adjuvant cisplatin-based chemotherapy should be strongly considered.
Radiotherapy in Urethral Cancer
Neoadjuvant radiotherapy can be used to downstage very large urethral tumors, particularly those locally invading the pubic rami.
Adjuvant radiation can be used to treat patients with bulky tumors and positive margins at surgical resection.
Chemoradiation therapy is an acceptable multimodal treatment especially for patients with squamous cell histology.
