Genetic testing can provide useful information to guide treatment in breast and ovarian cancer patients not previously tested, according to a new U.K. study.
In this, the study’s pilot phase, 3,525 patients diagnosed between 2015 and 2018 were invited to take part using a simple, home‑based saliva test. By March 2026, 43.7% had accepted the invitation. Testing showed inherited cancer‑related gene variants in 8.6% of patients with breast cancer and 10.1% with ovarian cancer.
These findings were presented at the ESMO Breast Cancer 2026 congress by Clare Turnbull, PhD.
“A particularly important group are women who survived young‑onset breast cancer and may now be approaching the age at which, if they carry a germline pathogenic variant in BRCA1 or BRCA2, their risk of ovarian cancer becomes very high,” Turnbull told Inside Precision Medicine. She is professor of translational cancer genetics at the Institute of Cancer Research in London, and member of the ESMO Precision Oncology Task Force.
Hundreds of thousands of cancer survivors have never been genetically tested, either because testing was not available when they were diagnosed or it was not routinely offered then. But, these researchers say, such patients are just as likely as those diagnosed today to carry a germline pathogenic variant that increases cancer risk.
This pilot is part of the U.K.-only Retrospective Genetic Testing Programme, which uses National Health Service (NHS) records to identify patients with breast and ovarian cancer who hadn’t yet been offered genetic testing, but were eligible for it based on tumor characteristics.
“With widespread capacity issues in NHS clinical genetics services, the RGT Programme offers a unique solution to the task of offering genetic testing to this cohort. The RGT Programme offers testing via our previously trialed ‘BRCA-DIRECT’ pathway, a clinician-light, at-home genetic testing pathway,” Turnbull said.
The pilot focused on patient groups with a strong likelihood of hereditary cancer, including triple‑negative, bilateral and young‑onset breast cancer, as well as high‑grade serous ovarian cancer.
“Our program tests patients for either seven genes known to be associated with breast cancer (BRCA1, BRCA2, PALB2, CHEK2, ATM, RAD51C and RAD51D) or nine genes associated with ovarian cancer (BRCA1, BRCA2, BRIP1, MLH1, MSH2, MSH6. PALB2, RAD51C and RAD51D),” said Turnbull.
Cancer susceptibility genes are broadly separated into low-, moderate- and high-risk genes. Within the RGT program, only high-risk and some moderate-risk genes are included on testing panels.
The study also suggests that a simplified approach to genetic testing—the BRCA‑DIRECT pathway—is potentially feasible at scale, without increasing workload for healthcare professionals.
“This approach allows healthcare professionals to focus their time where it is most needed, particularly on individuals with positive or complex results,” said Antonio Marra, MD, medical oncologist at the European Institute of Oncology (IEO IRCCS) in Milan, Italy, in a press release. Marra was not involved in the study.
There are other potential benefits of this approach.
“This has important implications for the efficient use of healthcare resources,” said Marra. “Identifying patients at scale enables more targeted interventions and a more effective allocation of clinical expertise and infrastructure.”
“Based on the program’s early outcomes and the integration of the BRCA‑DIRECT pathway into routine care, the NHS is commissioning a broader range of direct‑to‑patient genetic tests, with potential expansion to prostate, pancreatic and colorectal cancer patients,” Turnbull said.
She added that, “While increasing the availability of genetic testing is important, automatic genetic testing is unlikely to be the solution. Genetic testing is a highly personal choice, and some individuals may not wish to pursue testing.”
