Investigating a cluster of vulvar cancer in young women: a cross-sectional study of genital human papillomavirus prevalence.

BACKGROUND: Vulvar cancer is a relatively rare malignancy, which occurs most often in postmenopausal women. We have previously identified a geographic cluster of vulvar cancer in young Indigenous women living in remote communities in the Arnhem Land region of Australia. In this population, we investigated the prevalence of oncogenic human papillomavirus (HPV) infection in anogenital samples (vulvar/vaginal/perianal area and cervix) and compared the overall, type-specific and multiple infection prevalence between sites. METHODS: A cross-sectional survey of 551 Indigenous women aged 18-60 years was undertaken in 9 Arnhem Land communities. Women were consented for HPV detection and genotyping collected by a combined vulvar/vaginal/perianal (VVP) sweep swab and a separate PreservCyt endocervical sample collected during Pap cytology screening. HPV DNA testing was undertaken using PCR with broad spectrum L1 consensus PGMY09/11 primers with genotyping of positive samples by Roche Linear Array. The primary outcomes were the prevalence of cervical and VVP high-risk (HR) HPV. RESULTS: The prevalence of VVP HR-HPV was 39%, which was significantly higher than the cervical HR-HPV prevalence (26%, p<0.0001). HPV-16 was the most common genotype detected in both sites (VVP 11%, cervical 6%). HPV-16 infection peaked in women aged <20 years; however, there was a marked decline in cervical HPV-16 prevalence with age (p=0.007), whereas following an initial decline, the prevalence of VVP HPV-16 remained constant in subsequent age-groups (p=0.835). CONCLUSIONS: In this population experiencing a cluster of vulvar cancer, the prevalence of cervical oncogenic HPV infection was similar to that reported by studies of other Australian women; however there was a significantly higher prevalence of vulvar/vaginal/perianal infection to cervical. The large discrepancy in HPV prevalence between anogenital sites in this population may represent more persistent infection at the vulva. This needs further investigation, including the presence of possible environmental and/or genetic factors that may impair host immunity.

Cervical cancer: effect of glandular cell type on prognosis, treatment, and survival.

OBJECTIVE: To investigate survivals from cervical cancer, with special reference to effects of glandular histology and its influence on prognostic characteristics and management decisions. METHODS: Data on cervical cancers, diagnosed in 1984-2000, were obtained from the gynecologic oncology registry of hospitals of the University of Adelaide. Comparisons were made of disease-specific survival, age at diagnosis, diagnostic period, stage, grade, and primary course of treatment. RESULTS: The study included 544 squamous cell carcinomas, 43 adenosquamous carcinomas, five clear cell cancers, 136 other adenocarcinomas, and 19 cancers of "other" histological type. Overall survival was 72.2% at 5 years from diagnosis, decreasing to 67.5% at 15 years. Survival was lower for older ages, higher grades, and higher International Federation of Gynecology and Obstetrics stages, although equivalent for stages IIA and IIB. Unadjusted survivals varied by histological type (P =.001), with lower survivals suggested for adenosquamous and clear cell lesions and "other" histological types than for squamous cell carcinomas and other adenocarcinomas. After adjusting for age, stage, grade, and diagnostic period, adenocarcinomas had a higher case fatality than squamous cell lesions (relative risk 2.08, 95% confidence limit 1.35, 3.21), whereas the elevation in relative risk was lower and not statistically significant for a combined adenosquamous and clear cell category at 1.25 (0.69, 2.24). For stage II, both adenocarcinomas and the adenosquamous and clear cell group had lower survivals than squamous cell cancers. CONCLUSION: Relative to squamous cell carcinomas, adenocarcinomas and potentially adenosquamous cancers are becoming more common. This has implications for screening, treatment, and prognosis.