MALIGNANT TUMORS I—PRIMARY
Primary carcinoma of the vagina comprises approximately 1% of all malignancies in the female genital tract and ranks after carcinomas of the cervix, endometrium, ovary, and vulva in order of frequency. The lesion is most often located on the posterior vaginal wall and in the upper half of the vagina. Its early stage may be a small, irregular ulceration or a papillary, friable growth. The disease spreads by direct extension and gradually infiltrates the lateral and anterior walls of the vagina, extends into the rectovaginal or vesicovaginal septum, and eventually invades adjacent pelvic viscera. Later, the tumor disseminates by way of the pelvic lymphatics to the lymph glands in the iliac, obturator, and hypogastric areas. Distant metastases are rare.
The differential diagnosis must exclude the venereal granuloma and the
possibility that the tumor is secondary. Laboratory diagnosis by vaginal biopsy
is conclusive. Nearly always, vaginal cancer is of the squamous cell type and
may be either a well-differentiated epithelioma or a wildly growing anaplastic
tumor. The strongest association is between squamous cell carcinoma and human
papilloma virus (HPV) types 16 and 18 infections. The exceedingly rare
adenocarcinoma of the vagina probably arises in aberrant cervical glands of
müllerian origin or in remnants of the meso- nephric duct.
Radiation is probably the best overall type of therapy except in very
early stage disease. Radium needles can be inserted interstitially and should
be followed by deep x-ray therapy to the pelvis. If radical surgery is undertaken,
it may be possible to remove the vaginal lesion with a wide margin, but a
satisfactory excision frequently necessitates the sacrifice of the adjacent
bladder or rectum as well as the pelvic and inguinal lymphatic drainage from
the area. The 5-year salvage following either form of treatment is very low
when the tumor is advanced.
Even more uncommon than carcinoma of the vagina are malignant tumors of
connective tissue origin. Vaginal sarcomas are of two main histologic types.
One occurs chiefly in adults and occupies a typical position in the muscle or
submucosal layers of the posterior vaginal wall, elevating and ulcerating the
epithelium above it. Because these tumors tend to outgrow their blood supply, a
wide area may slough. Growth proceeds by direct extension to involve the entire
vagina, but hematogenous spread may also occur, with metastases to the lungs
and other distant organs. Microscopically, these sarcomas may be of spindle
cell, round cell, or mixed cell types.
A rare form of sarcoma (embryonal rhabdomyosarcoma) is generally found in
the vagina of young girls. Rarely, these tumors may arise from the cervix.
Although the cervical form of sarcoma is histologically similar to the vaginal
form, the prognosis for the cervical form is better. Grossly, it forms large
grapelike clusters of tissue, which eventually protrude from the vaginal orifice
and cause bleeding and foul discharge as a result of superficial necrosis. The
tumor is often multicentric, with loose
myxomatous stroma containing malignant pleomorphic cells and eosinophilic
rhabdo- myoblasts that have characteristic cross-striations (strap cells).
Treatment is surgical excision combined with multiagent chemotherapy.
Adjunctive radiation therapy has also been advocated but is generally reserved
for those with residual disease.
Melanoma of the vagina is unusual, but an occasional case is reported. A
primary focus elsewhere must be sought, because
disease in this area is more often secondary. It does not differ in its gross
or microscopic appearance from melanomas elsewhere. The large, anaplastic,
pigmented cells are pathognomonic. Melanoma in the vagina is almost uniformly
fatal.
Other rare primary malignancies of the vagina have been reported, including teratomas and clear cell carcinomas, the latter associated with maternal use of diethylstilbestrol during pregnancy.
