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PANTHER Study: Treating anal neoplasia in people living with HIV

The challenge

Anal cancer is a highly stigmatised condition, caused almost exclusively by persistent human papillomavirus (HPV) infection. The disease is rare in the general population, but in certain populations the risk can be up to 130 times higher. People living with HIV, especially gay, bisexual, and other men who have sex with men, are at the greatest risk.

Published in 2022, the ANCHOR study showed treatment of anal pre-cancerous lesions reduced incidence of anal cancer by 57%. Australia currently lacks guidelines on treatment for anal cancer. Evidence is needed on what treatment is most effective to prevent lesions developing into cancer.

The project

This pilot study will look at how effective electrocautery treatment is in removing anal high-grade squamous intraepithelial lesions (HSIL) and preventing them from becoming cancer. We will treat people living with HIV who have persistent HSIL with electrocautery at St Vincent’s Hospital, Sydney a maximum of five times. We will then assess whether the HSIL has cleared, partially cleared, or not cleared after electrocautery. We will also look at whether HPV infection has cleared or not, and whether HSIL methylation markers predict treatment outcomes. In qualitative interviews we will explore patients’ experiences of the treatment.

The method

We will be recruiting 100 people living with HIV, aged ≥18 years, who are currently patients at the Dysplasia and Anal Cancer Services (DACS) clinic at St Vincent’s Hospital, Sydney, with persistent HSIL. We will treat their lesion(s) with electrocautery, which works by heat destruction of targeted cells. We will observe whether lesions completely clear, partially clear, or do not clear. The aim is to evaluate how effective electrocautery treatment is in removing anal high-grade squamous intraepithelial lesions (HSIL) and preventing them from becoming cancer. Since this is the first trial of electrocautery in Australia, it is a pilot study.

The impact

The ANCHOR study was the first trial showing that treatment of anal lesions can prevent cancer in people living with HIV. With publication of the first international consensus guidelines on anal cancer screening in January 2024, there is a considerable interest in the field of screening and treatment for anal cancer. The ANCHOR study used mainly, but not exclusively, electrocautery as part of their treatment strategy, and the PANTHER study will look specifically at how effective electrocautery treatment is for anal cancer prevention. The results will determine if larger studies are needed and inform Australian guidelines for treating anal cancer.

Project collaborators

Co-Principal Investigator

  • Dr Mary Poynten, Kirby Institute

Chief Investigator

  • Scientia Professor Andrew Grulich, Kirby Institute

Site Principal Investigator and Co-investigator

  • Professor Richard Hillman, St Vincent’s Hospital, Sydney

Site Treatment Lead Investigator and Co-investigator

  • Dr Carmella Law, St Vincent’s Hospital, Sydney


  • Dr Fengyi Jin, Kirby Institute
  • Dr Penelope De Lacavalerie, St Vincent’s Hospital, Sydney
  • Dr Hamish Urquhart, St Vincent’s Hospital, Sydney
  • Dr Jennifer Roberts, Douglass Hanly Moir Pathology, Sydney
  • Dr Clare Dyer, Kirby Institute
  • Dr Nathanael Wells, Kirby Institute
  • Jane Costello, Positive Life NSW

Operational Team

  • Barbara Yeung, Kirby Institute
  • Portia Westall, Kirby Institute
  • Doug Fraser, Kirby Institute
Project funding

This project is funded by a generous philanthropic donation from The Glendonbrook Foundation.