What is urethral cancer
Urethral cancer is the rarest of all urological cancers and occurs most often after the age of 50. Certain types of human papillomavirus (HPV) may be its cause.
The urethra is a hollow tube that allows urine to pass from the bladder to the outside of the body. In men, the urethra is about 20 centimeters long and runs through the prostate to the end of the penis. In women, the urethra is about 5 centimeters long and opens outward just above the vaginal opening.
Subtypes of urethral cancer
There are three types of urethral cancer:
- Squamous cell carcinoma – is the most common type of urethral cancer. In women, it starts in the part of the urethra near the bladder. In men, it forms in the cells that line the urethra inside the penis;
- Transitional cell carcinoma – in women, cancerous cells grow near the urethra opening. In men, they grow where it goes through the prostate;
- Adenocarcinoma – in this type of urethral cancer, cancer cells start growing in the glands around the urethra.
Symptoms and Signs of Urethral Cancer
In early stages, there may not be many symptoms. As the cancer grows, some patients may notice a lump or tumor in the groin or penis. Others may experience pain or bleeding while urinating. If the tumor restricts the urethral canal, patients may have trouble urinating.
In women, the first symptom is usually the presence of blood in urine. If the amount is small, it is often only detected in laboratory tests when observed under a microscope. In both men and women, the urine flow may become obstructed, making urination difficult or the urine output slow and thin.
Diagnosis of urethral cancer
After clinical examination, if the doctor suspects cancer they will order tests for diagnostic confirmation. The main ones are:
- Cytoscopy – using equipment called a cytoscope, the exam allows checking inside the urethra;
- Biopsy – in this exam, cells taken from urethra and bladder are examined under a microscope to check for signs of cancer;
- Imaging tests – cancer cells can move to other parts of the body through the tissue, blood and lymphatic system. To detect whether other organs have been contaminated, imaging tests are ordered, such as chest X-ray, pelvis and abdomen CT scan, or pelvis MRI scan. These tests also help in staging the cancer and defining optimal therapeutic approach;
- Urethrography – is a procedure that helps the doctor see if the cancer has reached tissue near the urethra. For image definition, contrast dye is injected into the urethra and bladder.
Surgery is the most common treatment for urethral cancer. There are many different methods that can be used, depending on whether the tumor is superficial or invasive and the patient’s health conditions.
Surgery on superficial cancers – if the tumor has not spread to nearby tissues, it can be removed with a special cystoscope, called a resectoscope, inserted into the urethra to remove any abnormal tissues or tumors. This procedure is performed under both general anesthesia and local anesthesia.
Surgery on invasive tumors – most often, cancers in the anterior urethra (the part closest to the outside) can be treated well with local surgery. Tumors involving the posterior urethra (the part closest to the bladder) usually need more radical surgery to get the best result. The type of procedure depends on the location of the tumor and the organ, whether male or female, for example:
- Anterior urethra in men – men with a tumor involving only this part of the urethra (inside the penis) may need partial or complete penis removal. This depends on where the tumor is;
- Posterior urethra in men – if the tumor is in this area, bladder and prostate, part of the bony pelvis, and penis are at risk. If surgery is needed to remove these organs, a piece of the intestine is used to make a pouch. The kidneys can then drain urine into the pouch;
- Posterior urethra in women – since female urethra is short, it is rare to have a small tumor far enough from the urethral sphincter (the muscle that controls the release of urine) to remove it and still be able to urinate normally. The outermost third of the urethra can be removed without too many problems. If it is the innermost part, the urethra, bladder and a part of the vagina are often removed. A pouch can be made with part of the intestines for the kidneys to drain urine;
- Lymph node removal – pelvis lymph nodes are often removed in men and women undergoing these surgeries. A side effect in some people is leg swelling. Since these nodes drain fluid from blood vessels into the legs, their removal might trigger buildup.
Radiation therapy – Radiation destroys cancer cells at the site. Radiation therapy can be used on its own, with surgery, or with chemotherapy. This method allows patients to keep the urethra and neighboring organs, but with some possible side effects such as:
- Bladder pain;
- Rectal pain (or vaginal pain in women) and bleeding;
- Urethra narrowing, causing signs of blocked urine.
Chemotherapy – since it is a systemic treatment, it is most often used when the cancer has spread to other organs or body parts. It may be offered before surgery or radiation therapy. It can also be used after other treatments to kill cancerous cells outside surgery or radiation sites. The type of drug used depends on tumor spreading risk, amount of metastases (tumors outside the urethra), and specific tumor type (made of urothelial or squamous cells)
The exact cause of urethral cancer is not known, so there is no safe, efficient method of prevention.
What we know is that swelling and prolonged infection can increase cancer risk. Many men with urethral cancer have been previously treated for urethral stenosis disease or sexually transmitted infections. Many women with urethral cancer have been previously treated for urethral caruncle (mass), urethral diverticulum (external pouch), or chronic urinary tract infection. In both men and women, the human papilloma virus (HPV) has been associated with urethral cancer.