A team of British researchers has identified genetic clues that may help reveal which cases of breast cancer are more likely to recur. The new findings could enable doctors to determine which patients are at high risk of recurrence when their disease is first diagnosed and then target the genes that drive relapses in order to prevent the cancer’s return. The investigators, from the Wellcome Trust Sanger Institute in Cambridge, discovered that the genetic contributors underlying breast cancer recurrences are different from the ones seen in cases that don’t return. The team estimated that one in five patients with breast cancer experiences a recurrence, either in the same place as the original tumor or elsewhere in the body. They analyzed genetic data from 1,000 breast cancer patients, including 161 samples from cases that recurred. The investigators found differences in mutations that were linked to recurrence. They reported that some of these genetic changes were acquired when the cancers returned and began to spread. A subset of the mutations are “relatively uncommon among cancers that do not relapse”, said study leader Dr. Lucy Yates, adding that “some of these genetic alterations are potentially targetable with drugs”. The results of the British study were presented at the European Cancer Congress’ September 2015 meeting.
My take? The findings from this study are welcome news. At present, we have limited therapeutic interventions that are focused on preventing breast cancer recurrence, and nothing as powerful as targeting the responsible genetic mutations would be. The researchers explained that if individual cancers can change genetically over time, treatments that target a particular mutation may also have to change as the disease progresses. Therapies would have to be guided by taking regular samples of cancer tissue, rather than basing treatment only on samples taken when the cancer is first diagnosed. We’re not there yet, but if these study findings prove their promise, we could be on the road to developing effective strategies aimed at preventing breast cancer recurrences.