Almost all anal cancer is caused by high risk human papillomavirus (HRHPV). The majority of anal cancer cases occur in women, with rates 1.5 to 2-fold that of rates in men. Women with prior lower genital tract cancers (LGT, vulva, vagina and cervix) are at disproportionate risk, with between 10-50-fold higher risk of anal cancer compared with women in the general population. There is no consensus on how to screen for anal HPV and the precursor lesions, high grade squamous intraepithelial lesions.
This pilot study aims to examine the uptake and results of an anal cancer screening program in women with prior LGT cancer.
100 women diagnosed with cervical, vaginal or vulva cancer, aged 18 years or greater, and currently undergoing post-treatment follow-up will be enrolled at Chris O'Brien Lifehouse or Prince of Wales Private Hospital. Participants will undergo a digital anorectal examination (DARE), a lower vaginal/vulvar swab, a cervical/upper vaginal swab and an anal swab for HPV and p16/Ki67 testing. Participants with positive baseline results will be referred for St Vincent's Hospital for a high resolution anoscopy with biopsy of any abnormal lesions. Women will complete a questionnaire on the acceptability of the study screening procedures.
The study is ongoing. By September 2022, 48 participants were enrolled, with 7 providing demographic information only. Six (14.6%) had HRHPV detected and 8 (19.5%) had positive p16/Ki 67 staining. Nine have been referred for high resolution anoscopy.
This research study aims to address this health disparity by investigating novel screening methodologies, alone and in combination, to provide evidence for prevention strategies for women at high risk of anal cancer. We aim to help answer whether anal HRHPV testing will identify women with previous LGT cancer at high risk of anal cancer.
Chris O'Brien LifeHouse, Camperdown, NSW; Prince of Wales Private Hospital, Randwick, NSW; St Vincent's Hospital, Darlinghurst, NSW; Douglass Hanly Moir Pathology, Macquarie Park, NSW.
Glendonbrook Foundation, NHMRC.