Urethral cancer is an extremely rare malignancy, accounting for less than one percent of all cancers. It originates in the tube responsible for carrying urine from the bladder out of the body. This diagnosis is uncommon, making information about it less readily available to the public. This article provides clear details about the disease, including risk factors, signs that warrant medical evaluation, and current methods used for diagnosis and management.
Understanding the Urethra and Cancer Types
The urethra is a hollow tube whose length and structure differ significantly between the sexes. In women, the urethra is short (about 1.5 inches), extending from the bladder to an opening just above the vagina. The male urethra is significantly longer (approximately eight inches), passing through the prostate and the penis, and also serves as the passage for semen. These anatomical distinctions influence the location and type of cancer that is likely to develop.
Cancers are classified by the cell type where they originate, with three main types affecting the urethra. Transitional cell carcinoma (TCC), also called urothelial carcinoma, develops in the cells lining the part of the urethra closer to the bladder and is the most common type overall in men. Squamous cell carcinoma (SCC) starts in the flat, thin cells lining the urethra, often found near the tip of the penis in men and near the external opening in women. Adenocarcinoma forms in the mucus-secreting glands located around the urethra.
The location of the tumor is described as either proximal, meaning closer to the bladder, or distal, which is closer to the body’s exterior. Transitional cell carcinoma typically occurs in the proximal urethra, while squamous cell carcinoma is more common in the distal urethra. Adenocarcinoma is often associated with pockets or outpouchings within the urethra known as urethral diverticula.
Who Is At Risk
Certain factors are associated with an increased chance of developing urethral cancer, many of which involve chronic irritation or inflammation of the lining. Long-term inflammation stemming from conditions such as urethral strictures (narrowings of the tube) or chronic infections may contribute to the development of this cancer. Exposure to the human papillomavirus (HPV) is also considered a factor, as this infection can lead to chronic inflammation and is linked to several genital cancers.
Individuals with a prior history of bladder cancer have an elevated risk because the lining of the bladder and the proximal urethra share the same cell type. Smoking is another known factor, as the carcinogens in tobacco smoke are expelled in the urine and can affect the cells lining the urinary tract, including the urethra. Additionally, prolonged use of an indwelling catheter, which causes mechanical irritation, or previous radiation therapy to the pelvic area are recognized as risk factors.
Signs That Require Medical Attention
The physical changes caused by urethral cancer often overlap with symptoms of less serious urinary conditions, which can sometimes delay diagnosis. Hematuria, or blood in the urine, is a frequent sign, which may be visible or only detectable through laboratory tests. Patients may also experience dysuria (pain or a burning sensation during urination) or an increased frequency of needing to pass urine.
Changes in the urinary stream are also common indicators of a potential blockage, presenting as a weak, hesitant, or interrupted flow. In men, a lump or thickening may be felt along the penis, while in women, a mass may be palpable in the perineal area. Other signs that warrant investigation include abnormal discharge from the urethra (clear, white, or blood-tinged) and noticeable swelling of the lymph nodes in the groin area.
How Doctors Confirm the Diagnosis
Diagnosis involves a sequence of specialized medical procedures to confirm the cancer and determine its extent. The initial step is a comprehensive physical examination, checking for masses or swelling in the genital and groin regions. This is followed by a urinalysis and urine cytology, where a sample is examined for the presence of blood or abnormal cells.
Visualization of the urinary tract is performed using a cystoscopy, where a thin, lighted tube with a camera is inserted through the urethra to examine the lining and the bladder. During this process, a tissue sample (biopsy) is collected from any suspicious areas. This sample is analyzed by a pathologist, which definitively confirms the presence and type of cancer.
To assess the tumor’s size, depth of invasion, and possible spread (staging), imaging scans are ordered. These include computed tomography (CT) scans of the chest, abdomen, and pelvis. Magnetic resonance imaging (MRI) of the pelvis provides detailed images of the tumor’s local extent and regional lymph nodes.
Managing Urethral Cancer
Treatment plans depend on the tumor’s location, size, and depth of invasion. For smaller, less invasive tumors, particularly in the distal urethra, treatment may involve transurethral resection, where the tumor is removed using instruments passed through the urethra. Larger tumors may require more extensive surgical removal, known as a partial or radical urethrectomy, which can involve removing part or all of the urethra and potentially nearby organs, such as the bladder or penis.
Radiation therapy uses high-energy rays to destroy cancer cells and may be employed as a primary treatment or combined with other modalities. This can be delivered externally or internally through brachytherapy, where radioactive sources are temporarily placed near the tumor. Chemotherapy, which uses cancer-fighting drugs, is often used in combination with surgery or radiation, particularly for advanced or aggressive disease. Management goals range from achieving a complete cure to palliation, which focuses on controlling symptoms and improving quality of life when the cancer is widespread.