Vulvar cancer: the Cinderella of gynaecological oncology.

Cancer of the vulva is a rare malignancy that increases progressively with age. The age-standardized incidence averages between 1 and 2 per 100,000 women in Western countries. The majority (80-90%) are squamous cell carcinomas, melanoma and adenocarcinoma each accounting for about 5% of cases. Internationally, the incidence of vulvar cancer varies more than 30-fold, the highest rates being seen in populations of Portuguese South America. In many populations the incidence appears to be stable but there is some evidence that the incidence of in situ carcinoma is increasing in the United States of America. Epidemiological studies have identified sexual factors, particularly human papilloma virus (HPV) infection, as increasing risk. Smoking also increases risk by interacting synergistically with HPV infection and genital warts. The aetiologies of vulvar intraepithelial neoplasia (VIN)3/in situ disease and invasive cancer appear to differ. VIN does not automatically progress to invasive cancer and is strongly associated with HPV infection. Many older women with invasive vulvar cancer do not have evidence of HPV and do not smoke. More research is needed on the cause of vulvar carcinoma in this group. Treatment has become more conservative over the years and this has reduced morbidity and probably mortality. Although FIGO data do not show much by way of improvement in survival, data from population-based cancer registries have shown definite increases in survival (5-year survival proportions in excess of 80%, when age and Stage have been taken into account). Improvement is particularly related to the preponderance of early stage disease.