CYSTS AND CANCER OF THE
SCROTUM
Sebaceous cysts (epidermoid, epidermal cysts) of the scrotal wall are not
uncommon. Derived from sebaceous glands in the skin, cysts form either from
over-production of secretions or as a result of obstruction of the gland
outlet. These cysts, usually scrotal, appear as smooth, round cystic tumors,
varying in size from a few millimeters to, in rare instances, 8 to 12 cm. Although usually solitary or few in number, the occurrence of several hundred
cysts has been described. The secretions contain cholesterol crystals and
degenerated epithelial cells, and the fibrous cyst capsule is lined by stratified
squamous epithelium with varying degrees of atrophy. Trichilemmal cysts (pilar
cysts) are clinically indistinguishable from sebaceous cysts but contain
keratinous rather than sebaceous material. Regarding the cyst type, inflammation
is common in the obstructed duct and can lead to infection and pain. Sebaceous
cysts are not precancerous but have been known to calcify. Definitive treatment
is surgical excision, best performed after infection has been quelled with
antibiotics. With excision, the entire epithelial sac that lines the cyst must
be removed to avoid recurrence.
Angiokeratoma is a skin
disorder characterized by the presence of multiple, small, punctate, violaceous
(purple) lesions on the scrotal, and occasionally penile, skin. There can be
hundreds of lesions present, but they are generally asymptomatic. They
represent slightly elevated areas of venous ectasia and appear similar to
punctate angiomas. As they are benign, treatment is usually unnecessary.
However, if they bleed, local fulguration is effective.
Carcinoma of the scrotum is
a rare cancer and for the most part an occupational disease confined to men
exposed to petroleum and its products. It was the first cancer shown to be
caused by an environmental carcinogen, and was named chimney-sweep’s cancer in
1775 after its association with soot by Sir Percival Pott. It also occurs in
men chronically exposed to tar, pitch, paraffin, shale, creosote, and crude
wool. It has been observed in weavers who lean across machinery, and whose
clothes become impregnated with oil, which then contacts the scrotum. It has
also been described after x-ray therapy to the scrotum or following the chronic
use of local treatments (PUVA [psoralen and ultraviolet A]) for scrotal
psoriasis. An occasional case is observed without a history of occupational
contact, and there may be an association with HPV type 18 virus. The malignancy
appears after two or three decades of exposure, usually between the ages of 45
and 70 years. The early lesion may be a small pimple or warty tumor that
ulcerates, or the lesion may begin as an ulcer and develop into a large
fungating mass.
Most carcinomas of the
scrotum are squamous in type, but melanomas, basal cell carcinomas, and
sarcomas have also been observed. Local remedies are usually applied without
benefit before clinical presentation with pain. In about 50% of cases,
metastases to inguinal lymph nodes are present when the patient is first seen.
Metastatic spread occurs relatively quickly as the thin scrotal wall lacks
natural barriers that tend to wall off neoplasia. Consistent with other
squamous cancers, dissemination occurs chiefly by lymphatic rather than hematogenous spread. If the malignancy has invaded the scrotal contents,
metastases may spread directly to the peri-aortic nodes. Possibly due to its
rarity or to the nature of scrotal cancers, there is little relation between
the duration of the cancer diagnosis, the grade of malignancy, and the
prevalence of lymph node involvement. In very early, localized cases, a 75%
cure rate is possible, with wide scrotal excision. Among those with lymph node
involvement, 25% of patients are cured with bilateral inguinal and femoral
lymphadenectomy. Bilateral
excision of draining lymph
nodes is necessary, as the lymphatic channels in the scrotum are richly
interconnected. The prognosis in metastatic cases is poor, and treatment can be
quite morbid. Direct extension of tumor to deep femoral, external iliac, and
hypogastric lymph nodes can occur, requiring dismemberment, lower limb removal,
and hemipelvectomy. Chemotherapy and radiotherapy can be considered for
downsizing tumors before resection but rarely result in cure when used as classic adjuvant therapy.
