Carcinoma

Aetiology

Circumcision soon after birth confers almost complete immunity against carcinoma of the penis. Later circumcision does not seem to have the same effect and Moslems cir­cumcised between the ages of 4 and 9 years are still liable to the disease. Chronic balanoposthitis in known to be a con­tributory factor and there are definite precarcinomatous states:

 leucoplakia of the glans is similar to the condition seen on the tongue;

  long-standing genital warts may rarely be the site of malignant change;

  Paget’s disease of the penis.

Paget’s disease of the penis (syn. erythroplasia of Querat) is ‘a persistent rawness of the glans like a long-standing balanitis followed by cancer of the substance of the penis’ (Sir James Pager). Treatment is by circumcision, observation and excision if the lesion does not resolve.

Pathology

Carcinoma of the penis may be flat and infiltrating or papillary (Fig. 67.24). The former often starts as leucoplakia and the latter results from an existing papilloma. Local growth continues for months or years. The earliest lymphatic spread is to the inguinal and then to the iliac nodes. Once the growth breaches the partial barrier formed by the fascial sheath of the corpora cavernosa it spreads rapidly and iliac lymph node involvement is common (Fig. 67.25). Distant metastatic deposits are infrequent.

Clinical features

Forty per cent of patients are under 40 years of age. The early symptoms of mild discomfort and light discharge are often neglected and the disease progresses slowly. By the time the patient presents, the growth is often large and secondary infection causes a foul bloody discharge. There is little or no pain.

Sixty per cent have inguinal lymph node enlargement when they present but in half this is reactive enlargement due to sepsis. In most the prepuce is non retractile and must be split to view the lesion. A biopsy should be performed to make the diagnosis.

Untreated, the whole glans may be replaced by a fungating offensive mass. Later the inguinal nodes erode the skin of the groin and the death of the patient may be due to involvement of the femoral or external iliac artery with torrential haemorrhage.

Treatment

Radiotherapy is effective (60—70 per cent survival at 5 years) if the growth is small. Circumcision precedes treatment which may be delivered by implanted radioactive tantalum wires, external beam radiation or by means of a radioactive mould applicator applied externally to the penis.

Surgery is needed for large anaplastic growths, if there is infiltration of the shaft and when radiotherapy fails. Partial amputation is used for distal growths when adequate clear­ance of the tumour is possible. When an advanced, infiltrating or anaplastic lesion is present, total amputation is necessary.

Treatment of associated enlarged inguinal lymph nodes should usually be delayed until at least 3 weeks after local treatment to the primary lesion. Enlargement due to infection will usually show signs of subsiding with antibiotic treatment if necessary. Block dissection is indicated if there is persistent enlargement which needle aspiration biopsy shows to be due to tumour. The 5-year survival rate falls to 35 per cent in these cases. If surgery to the nodes is impossible, radiotherapy may cause a worthwhile temporary regression.

Buschke—Lowenstein tumour is uncommon. It has the histological pattern of a verrucous carcinoma. It is locally destructive and invasive, but appears not to spread to lymph nodes or to metastasise. Treatment is by surgical excision.

Secondary cancer of the penis is uncommon as a result of spread from a primary tumour of the bladder, rectum or prostate.