For years, breast-cancer diagnosis and treatment have remained largely uniform for patients across the board, though each person's case is different. Now, research is emerging that pinpoints breast cancer not just to an organ, but to a number of cancer subtypes, leading to more personalized—and more effective—breast cancer treatment.
“The traditional view of cancer is that we give cancer types labels based on the organs they arise in, but another view on these diseases focuses on how the individual genomes of cancer are abnormal,” says Dr. Matthew Ellis, professor of medicine in the division of medical oncology at Washington University School of Medicine. “Mistakes in the genome that accumulate in the breast tissue are often what lead to cancer, but not all breast cancers have the same genetic mutations.”
Ellis and other researchers are trying to understand cancer at a fundamental level, analyzing cells and genetic mutations. We all inherit healthy DNA, Ellis explains, but as we age, mutations start to occur. Some people accumulate these mutations, or genetic errors, faster than others.
“Ten years ago we were able to see how active genes are and how genes make messenger DNA to make proteins, which gave rise to the idea that breast cancer falls into five or six subgroups,” Ellis says. “Now, we’re able to look at how the gene copy changes across the entire genome. The fact that this is possible is absolutely astonishing.”
Ellis believes that in five to 10 years, patients will receive full-genome sequencing as part of the diagnostic process. Identifying cancer subtypes in each patient will lead to individually tailored treatments that are more effective and efficient.