Vaginal cancer
Epidemiology and aetiology of vaginal cancer
Primary cancer of the vagina is a rare disease and accounts for only 1-2% of all gynaecological malignancies. The incidence is estimated to be 0.42/100,000 women per year and is increasing with age (95).
Median age at diagnosis is 65-70 years. Cases should only be classified as vaginal cancer after exclusion of cervical, urethral, or vulval origin of the disease, as stated by FIGO (96).The most common histological type is squamous cell carcinomas, accounting for approximately 75% of all vaginal cancers (97). Squamous cell carcinomas can be associated with HPV (98). Suggested risk factors are prior hysterectomy (98, 99), prior vaginal pessary use (due to chronic irritant vaginitis) (100), and finally patients with a history of cervical cancer (presumably because these sites share the same exposure and susceptibility to HPV). However, despite these associations also in these patients, vaginal cancer remains a rare disease, thereby not justifying screening strategies.
Clear cell carcinomas are a rare subtype and are associated with adenosis of the vagina. They usually occur in women below the age of 30 years. Adenosis of the vagina is most commonly seen in women exposed to diethylstilbestrol (DES) in utero (101). The drug was prescribed to women between 1948 and 1977 to reduce the risk of miscarriage. Women with DES exposure in utero are screened yearly for the presence of adenosis and/or vaginal cancer.
Malignant melanoma can also be located in the vagina. Malignant melanomas of the vagina are very rare. The overall prognosis is poor, as many patients present with deeply infiltrating lesions at the time of diagnosis.
Clinical features and diagnosis of vaginal cancer
The most common symptoms of vaginal cancer are painless vaginal bleeding and/or discharge. In more advanced local disease, urinary problems, tenesmus, constipation, blood in stool, and pelvic pain might be involved, depending on the localization of the vaginal tumour (anterior or posterior wall of vagina, more proximal or distal in vagina).
Physical examination may reveal a vaginal mass or ulcer. Diagnosis is confirmed by a biopsy. Primary spread occurs especially to the regional lymph nodes (for tumours in proximal vagina: to the pelvic lymph nodes; in distal vagina: to groin lymph nodes). Frequent sites of distant metastases are lung and liver (98).Staging of vaginal cancer
Staging is based on clinical criteria. Examination under general anaesthesia is often the best way to get a good impression of the extension of the tumour. Imaging of the thorax and the abdomen with CT should be performed to exclude distant metastases. The current staging system is summarized in Table 65.6. MRI has an increasing role in diagnosis, staging, and treatment planning of vaginal cancer (102).
Treatment of vaginal cancer
Treatment of vaginal cancer must be individualized and varies depending on the stage of disease and site of vaginal involvement. In most patients the primary treatment modality is radiotherapy, and can consist of external radiation and brachytherapy. The distal one-third of the vagina drains to the inguinofemoral lymph nodes. When the vaginal tumour is in the distal one-third, these nodes should be involved in the target volume of the radiotherapy as well (103).
Experience with chemoradiation in vaginal cancer is limited. Often for larger tumours, chemotherapy is added, extrapolating the results in cervical cancer that has a similar biology. The rareness of vaginal cancer makes it very hard to ever perform randomized trials on this subject.
Surgery has a limited role in the management of vaginal cancer, because of the radicality required to achieve clear surgical margins. However, in selected cases surgery is possible. For example, patients with a proximal vaginal tumour can be treated like cervical cancer patients with a radical hysterectomy, upper/partial vaginectomy, and pelvic lymphadenectomy. Small early-stage tumours near to the hymen can be treated like vulval cancer, with local excision of the primary tumour combined with inguinofemoral lymphadenectomy.
Table 65.6 FIGO staging of vaginal cancer
| Stage 0 | Carcinoma in situ |
| Stage I | Carcinoma limited to vaginal wall |
| Stage II | Carcinoma has involved subvaginal tissue but has not extended to the pelvic wall |
| Stage III | Carcinoma has extended to the pelvic wall |
| Stage IV | Carcinoma has extended beyond the true pelvis or has involved the musosa of the bladder and/or rectum |
| Stage IVA Stage IVB | Spread of the growth to adjacent organs Spread to distant organs |
Prognosis of vaginal cancer
Overall prognosis of vaginal cancer is poor, which is probably due to the frequent late stage at presentation (96). Vaginal cancer can recur in the vagina, pelvis, or at distant sites. The prognosis of recurrent disease is very poor. In selected cases, a pelvic exenteration may be one option.
Due to the rarity of the disease, patients with vaginal cancer should be referred to a tertiary oncology unit.