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.