Urethral Tumors

Tumors of the female or male urethra are extremely rare. In women, 75% of cases occur after age 50. In men, the peak incidence occurs at age 58. Perhaps the most striking etiologic insight into this disease is the detection of oncogenic forms of human papillomavirus (HPV) within the genome of urethral tumors (in > 60% of tumors in women; 30% in men [but far higher if tumors of just the distal male urethra are analyzed]). Consequently, in women, the urethra is now recognized as one of multiple potential sites of presumed HPV carcinogenesis, although the cervix remains by far the most common site of clinically significant disease.

Urethral tumors invade adjacent structures early in the course of disease and often are not diagnosed until they are locally advanced. Early metastasis affects the external groin nodes or the pelvic (obturator) nodes.

Symptoms, Signs, and Diagnosis

The majority of female patients have a long-standing history of urinary frequency; most have been treated for urethral syndrome--a complex and poorly understood condition of hypersensitivity of the pelvic floor. The development of hematuria and obstructive symptoms or even of frank urinary retention necessitates reevaluation of the woman's voiding problems. A urethral tumor is sometimes first diagnosed by a gynecologist as a vaginal mass.

In men, urethral tumors are extremely insidious. Only occasionally does the patient have hematuria or even bloody urethral discharge. A gradual onset of obstructive voiding symptoms (not unlike prostatism of bladder neck origin) is common. The majority of men present clinically in a manner indistinguishable from that of benign urethral stricture and are dilated routinely without a more extensive assessment. In more advanced cases, a perineal or penile mass is occasionally palpable; in the most extreme cases, a fungating mass with urethral fistulization is encountered.

Cystourethroscopy is the preferred diagnostic procedure. Staging is primarily by CT; MRI can help assess the extent of disease but is more accurate in men.

Treatment

Because of the rarity of these tumors, algorithms of optimal management have not been developed.

In women, small distal lesions generally can be incised and treated with adjuvant radiation therapy, if no gross evidence of nodal involvement is seen. More proximal lesions may be treated with interstitial brachytherapy (insertion of cytotoxic radiation-emitting pellets), but many require total anterior exenteration with wide excision of the anterior vagina (similar to treatment of bladder cancer in women).

In men, total emasculation with cystoprostatectomy and musculocutaneous flap reconstruction of the perineum may be necessary in advanced cases; adjuvant radiation therapy is usually also used in such cases. Chemotherapy has been used in conjunction with these tumors, but its value has not been established. Presence of groin adenopathy may require groin dissection; involvement of pelvic nodes may increase the extent of dissection, and such extended surgery into the pelvis is controversial because of the poor prognosis despite aggressive therapy.