The penis, along with the testicles, forms the male genitalia. Its function is to eliminate urine, as well as to ejaculate sperm. Inside the penis is a tube-like structure, the urethra, which is lined with epithelial cells. The rest of the organ is formed by erectile tissues called corpora cavernosa and corpus spongiosum, all covered by skin.
Penile cancers grow out of the squamous epithelium that forms the skin covering the penis. These cancers are called squamous cell carcinoma (SCC) and comprise the majority of cancers of the penis. Other very rare types include malignant melanoma and basal cell carcinoma.
The following are some risk factors associated with this cancer:
- HPV infection.
- Phimosis, or a tight foreskin.
- Other skin conditions, which can be precursors of SCC.
- Smoking, especially when combined with HPV infection.
- Age – men over 55 are much more likely to develop penile cancer, with an average age at diagnosis of 65.
- AIDS – immunocompromised people are more prone to develop the disease.
Signs and symptoms of penile cancer will most often involve changes in the skin of the penis. These changes can include: an area of the skin changing colour or thickness, a lump, an ulcer, a velvety rash, a small crusty bump, bluish-brown growths, and discharge and odour from the foreskin. When the cancer spreads, lymph nodes in the groin might also be noticeableably affected. However, this most often indicates an active infection, rather than cancer.
Prognosis and survival depend on many factors, including the stage, size, and grade of the tumour. Staging of the disease involves the size of the tumour, whether it has spread beyond the penis, and the type of cancer. Generally, cancers of the glans (tip of the penis) are low-grade, whereas those of the shaft are high-grade. Low-grade cancers have a better prognosis and survival rate.
Treatment for penile cancer begins with surgery, though the exact technique will depend on the stage and size of the tumour.
- Circumcision: removal of the foreskin.
- Mohs surgery: removal of the cancer in layers, little by little, until no cancer remains. It may be used to treat small, early-stage penile cancers.
- Laser surgery: an intense beam of light that may be used to treat small tumours, carcinoma in situ, or precancerous conditions of the penis.
- Cryosurgery: extreme cold to freeze and destroy tissue. It may also be used to treat low-grade penile cancers.
- Wide local excision: removal of the tumour, along with a margin of normal tissue around it.
- Glansectomy: removal of the head (glans) of the penis.
- Partial or total penectomy: removal of a part or the entire penis.
- Lymph node dissection.
Radiation therapy is used as an alternative to surgery in advanced stages of the disease. Chemotherapy can also be used topically (in cream form) or systemically to kill cancer cells throughout the body.