A new test that could help some women with breast cancer avoid unnecessary chemotherapy has been validated and recommended for use.
Developed by a team at St Vincent's University Hospital (SVUH) in Dublin, the test can help predict whether a tumour will spread to other sites in the body. The approach is now poised to help tailor the treatments of women who have been diagnosed with breast cancer.
The test measures levels of a key enzyme called uPA in breast tumour tissue, said Prof Joe Duffy, a cancer researcher at SVUH and University College Dublin's Conway Institute.
The enzyme plays a key role in metastasis, or spread of the cancer from the primary tumour in the breast to other sites such as the brain, bones, liver and lungs. These cancers at distant sites are generally the cause of death, explained Prof Duffy, who developed the test with Prof Niall O'Higgins and Dr Enda McDermott 10 years ago at SVUH.
Now following studies of more than 8,000 patients, uPA screening has just been recommended by the respected American Society of Clinical Oncology, which is effectively a worldwide recommendation, said Prof Duffy.
The test measures levels of uPA in removed tumour tissue, and the amounts present would influence the patient's management after surgery, he noted.
Where uPA levels are low, the cancer is less likely to spread. These women could avoid necessary chemotherapy and possibly benefit instead from other regimes such as hormone therapy, which has fewer side effects, explained Prof Duffy.
"It would improve their quality of life," he said. "And it's moving toward the concept of personalised treatment rather than giving the chemotherapy blunderbuss to all patients, regardless of whether it is suitable for them or not."
The uPA test is not currently in general use. "I would like to see it applied as soon as is practical, but we are talking years rather than months," said Prof Duffy.
The research was funded by the Irish Cancer Society and the Health Research Board.