BRCA: New Chemotherapy Regime Proves to Shrink Tumours Twice as Fast
A new chemotherapy regime has proved to shrink tumours twice as fast as in normal methods in patients with aggressive breast cancer carrying a faulty BRCA gene, according to a clinical trial.
The study, published in Nature Medicine, and funded by Cancer Research UK and Breast Cancer Now, shows that gene tests might benefit women with hard-to-treat breast cancer. Today, testing for a faulty BRCA gene is not routine.
Triple-negative breast cancer affects around 7,500 women in the UK each year. Hormone therapies used to treat the more common types of breast cancer don’t work on these tumour types.
“Women with triple-negative breast cancer often only survive for one to two years after the cancer has relapsed and spread to other parts of the body so there is an urgent need to find alternative treatments for this groups of patients,” said Prof. Judith Bliss from The Institute of Cancer Research, London.
A total of 376 women with advanced triple-negative breast cancer took part in the trial, where 43 of them had BRCA gene faults.
Half were treated with carboplatin (Paraplatin) and half received standard treatment, docetaxel (Taxotere).
Among the BRCA mutation carriers, carboplatin shrunk tumours in 68% of cases, while tumours with the faulty gene treated with docetaxel shrunk on average by 33%.
The participants who took carboplatin also had fewer side effects.
The molecules made by the BRCA genes are part of the machinery that repairs cells’ DNA if it becomes damaged. When BRCA is faulty, cancer-causing mistakes in the genetic code are more likely.
Carboplatin works by interfering with this DNA repair machinery, which is why the team think this drug was more effective.
The researchers believe that combining the drug’s effects with fault BRCA causes a double hit to the cell’s DNA repair efforts, which may overload the cancer cell’s DNA repair system, causing it to die.
Professor Charles Swanton, Cancer Research UK’s Chief Clinician called the study “exciting” and said it brings precise care for these patients closer.
“Rather than offering all women the same standard of care, these results show that, for patients with inherited BRCA mutations, the drug carboplatin is not only a more effective treatment option, but also comes with fewer side effects, sparing patients possible health problems, physical discomfort and emotional distress.”
Professor Andrew Tutt of The Institute of Cancer Research (ICR), London, who led the research, said the study strongly suggests that women with triple-negative breast cancer should be tested for faults in the BRCA genes as those who test positive might may benefit from carboplatin.
“It strongly suggests that many women with triple-negative breast cancer should be considered for testing for faults in the BRCA genes so those who test positive can benefit from carboplatin.”
“Using this simple test enables us to guide treatment for women within this type of breast cancer,” he continued. “I am keen for these findings to be brought into the clinic as soon as possible.”