Organ transplant recipients with advanced cancer, an often overlooked group in cancer care, may benefit from immunotherapy drugs, according to a new study.
The major international study, published in the prestigious JAMA Oncology journal, has revealed promising signs that cancer-fighting immunotherapy drugs, long considered too risky for organ transplant patients, may offer real benefits when carefully managed.
Lead author, Dr Nida Saleem, from Flinders Health and Medical Research Institute (FHMRI) and Department of Renal and Transplant Medicine, Westmead Hospital, says that solid organ transplant recipients (SOTRs) have historically faced difficult choices when diagnosed with advanced cancers.
"Powerful treatments like immune checkpoint inhibitors (ICIs), which activate the immune system to attack cancer, were often avoided due to fears that they could also trigger rejection of the transplanted organ," says Dr Saleem.
The multi-institutional study, co-led by Flinders University's FHMRI, University of Sydney, Westmead Hospital, and funded by the Westmead Hospital Foundation, systematically reviewed data from 343 transplant recipients worldwide. It found that many patients could safely access these life-extending treatments with tailored care.
"Among all transplant recipients studied, about one in three responded positively to ICI treatment after one year, a success rate on par with patients who had never undergone a transplant. However, about 36% still experienced rejection within one year of starting ICI treatment,' says Dr Saleem.
Transplant recipients with cutaneous squamous cell carcinoma, a common form of skin cancer, had a higher response rate to treatment (around 60% in the first year after treatment) and achieved survival outcomes comparable to those of the general population.
Co-author, Professor Billie Bonevski, Dean (Research) and Director of FHMRI, says these findings are especially meaningful given that transplant recipients have previously been left out of most cancer trials.
"This study fills a critical gap, showing that ICIs may work, even in complex cases," says Professor Bonevski.
While there are still challenges, including a risk of organ rejection-especially within the first few months of treatment-researchers found that a specific combination of drugs (mTOR inhibitors and steroids) may reduce these risks.
These medications help keep the immune system in check, potentially protecting the transplanted organ without blocking the benefits of immunotherapy.
This dual approach appears to maintain cancer-fighting power while supporting graft survival, a crucial step forward in creating safe treatment pathways for this vulnerable population.
Germaine Wong, Professor of Clinical Epidemiology at University of Sydney and Director of Renal and Transplant Medicine, Westmead Hospital, emphasised the importance of individualised treatments in transplant recipients with advanced-stage cancer.
"Cancer is a critically important outcome for transplant recipients, as it is the second leading cause of death in this population. This study provides valuable data to guide complex decisions, balancing the need to preserve graft function while treating advanced-stage cancer, and particularly in recipients with life-sustaining organs such as the lungs and hearts," says Professor Wong.
"It shows that immunotherapy can be a viable option for select transplant patients, especially when other options are limited."
While more research is needed, including trials that directly compare ICIs with other therapies in this group, this study lays the groundwork for more inclusive, hopeful cancer care for transplant recipients in the years ahead.
The paper, 'Outcomes of solid organ transplant recipients with advanced cancers receiving immune checkpoint inhibitors: A systematic review and individual participant data meta-analysis', by Nida Saleem, Jiayue Wang, Angela Rejuso, Armando Teixeira-Pinto, Jacqueline H Stephens, Annabelle Wilson, Anh Kieu, Ryan P Gately, Farzaneh Boroumand, Edmund Chung, Billie Bonevski, Matteo S Carlino, Robert Carroll, Wai H Lim, C Craig, Naoka Murakami and Germaine Wong is published in JAMA Oncology. DOI: 10.1001/jamaoncol.2025.2374.
See paper for full list of collaborating institutions.
Acknowledgements: This study was supported by the Westmead Hospital Research Foundation for the design and conduct of the study and collection, management, analysis, and interpretation of the data. GW is the recipient of the NHMRC Investigator Grant (APP 1195414).
