In a nutshell
Some background
Melanomas of the glans penis and male urethra are very rare, accounting for less than 0.1% of all melanomas. The glans penis is the area at the tip of the penis. The male urethra is a muscular tube that carries urine and semen through the penis to outside of the body. These melanomas occur in mucosal tissues (moist lining of a body cavity or structure such as the nose or mouth) and are known as mucosal melanoma. Mucosal melanoma is distinct from other types of melanoma and requires a different treatment approach. A comprehensive review on patient data to date would help develop an effective treatment for these melanomas in future.
Methods & findings
Ulceration (tumor breaking through skin’s surface) occurred in 39% of glans melanoma patients compared to 64% in urethral melanoma patients. 63% of the glans melanoma occurred at the back–side of the penis. For urethral melanoma, the most common location (73%) was the spongy area of the urethra located before the external opening of the glans penis.
For localized melanoma (melanoma confined to the site where it started), surgical removal of the tumor and sentinel lymph node biopsy (SLNB – involves taking a tissue sample to determine whether the cancer has spread to the lymph nodes [sites that hold the immune cells]) were the most common treatments used.
The average tumor thickness (how far the cancer reached into the skin) was 2.6 mm in glans melanoma patients and 5 mm in urethral melanoma patients. The average overall survival for all patients was 28 months. 10% of patients survived more than 5-years. Patients who survived more than 5–years had stage I melanoma (tumors less than 1 mm thick) with an average tumor depth of less than 3.5 mm. The average risk of cancer recurrence after surgery in patients with stage I melanoma was 15% which increased to 30% in some patients.
In patients with stage II melanoma (tumors between 1-2 mm thick) that has spread to the lymph nodes, the 2-year survival rate was nearly 0%. Chemotherapy and immunotherapy (treatment that boosts the immune response) has been used in combination to treat stage II melanoma. Dacarbazine (DTIC) and interleukin-2 (IL-2, Proleukin) are commonly used and have shown varied response rates from 3% to 23%.
The bottom line
The authors concluded that for localized melanoma of the glans penis and male urethra, surgery and SLNB were the treatments of choice. They further noted that for advanced stages, patient outcomes were poor.
Published By :
Urology
Date :
Jan 01, 2014
