Immunotherapy Outcome Predictions: Scientists Discover Strategies for Forecasting Effectiveness
In the ever-evolving war against cancer, immunotherapy is making strides as a potential treatment option. But it's not the silver bullet yet - not every person and not every cancer responds positively to immunotherapy. With that in mind, researchers from Johns Hopkins University have made a groundbreaking discovery: a specific subset of mutations in cancer tumors that hint at how much the tumor may benefit from immunotherapy.
Their findings, published in the journal Nature Medicine, could change the way doctors approach selecting patients for immunotherapy, as well as predicting outcomes from treatment.
Immunotherapy relies on boosting the body's immune system to help it fight off cancer cells. Normally, cancer cells evade the immune system by hiding behind mutations. Immunotherapy gives the immune system a much-needed boost, making it easier for it to find and destroy those hidden cancer cells.
Several types of cancer, such as breast cancer, melanoma, leukemia, and non-small cell lung cancer, are currently treated with immunotherapy. Researchers are investigating whether immunotherapy could also be effective for other types of cancer, like prostate cancer, brain cancer, and ovarian cancer.
To determine how well a tumor will respond to immunotherapy, doctors traditionally examine the total number of mutations in a tumor, called the tumor mutation burden (TMB). This helps doctors gain an idea of how "foreign" the cancer cells are to the immune system, making them more susceptible to attack.
But in this study, Johns Hopkins researchers went a step further. They identified a specific subset of mutations within the overall TMB, which they called "persistent mutations." These persistent mutations remain in the cancer cells despite the tumor evolving. This keeps the tumor visible to the immune system, making a better response to immunotherapy possible.
The presence of persistent mutations allows the immune system to mount and maintain an attack on the cancer cells, achieving sustained immunologic tumor control and long survival. In contrast, the overall tumor mutation burden isn't as accurate in predicting tumor responsiveness to immunotherapy.
"Persistent mutations are always there in cancer cells, and they may render the cancer cells continuously visible to the immune system, eliciting an immune response," explained Dr. Valsamo Anagnostou, a senior author of the study and an associate professor of oncology at Johns Hopkins.
"We believe that persistent mutations may help clinicians more accurately select patients for clinical trials of novel immunotherapies or predict a patient's clinical outcome with standard-of-care immune checkpoint blockade," said Anagnostou.
While immunotherapy is not a cure-all for cancer, the discovery of persistent mutations could revolutionize how doctors select patients for immunotherapy and predict treatment outcomes. With further research, this knowledge could spare countless people from undergoing unbeneficial or toxic treatments, bringing them one step closer to beating cancer.
Immunotherapy's potential in treating various medical conditions such as breast cancer, melanoma, leukemia, and non-small cell lung cancer is being investigated to extend its reach to other cancer types like prostate, brain, and ovarian cancer. Johns Hopkins University researchers have made a groundbreaking discovery of a specific subset of mutations in cancer tumors, named "persistent mutations," which could aid doctors in better selecting patients for immunotherapy and predicting treatment outcomes. According to Dr. Valsamo Anagnostou, a senior author of the study and an associate professor of oncology at Johns Hopkins, persistent mutations remain in the cancer cells despite tumor evolution, making the tumor continuously visible to the immune system, which could elicit a stronger immune response and lead to sustained immunologic tumor control and long survival.