In a study presented at the American Association for Cancer Research's annual meeting, researchers report encouraging early results from research investigating a potential way to help some cancer patients avoid surgery.

According to the results of the early study, published simultaneously in the New England Journal of Medicine, 92% of patients who received only an immune-based treatment to help their own immune systems shrink their tumors—and no surgery, which is generally the standard treatment for them—showed no detectable signs of disease after two years.

Maureen Sideris, 71, was one of those patients. The New York resident was diagnosed with gastroesophageal junction cancer in 2022 after she noticed it was difficult for her to swallow and digest food. When she saw a cancer surgeon, he told her that surgery to remove the tumor they had detected would be her best treatment option. He also informed her that she would need chemotherapy and radiation following the surgery to kill as much of the cancer as possible. “I was freaking out,” says Sideris. For a certain period after the surgery, she wouldn’t be able to talk or lie flat at night to sleep. Then there was the chemotherapy and radiation. “There were a lot of steps to the recovery.”

But based on the genetics of her cancer, she was told about a study of a new approach being pioneered by Dr. Andrea Cercek, section head of colorectal cancer at Memorial Sloan Kettering Cancer Center. Cercek was testing whether people like Sideris could be treated with a checkpoint inhibitor, a relatively new type of cancer treatment that frees the body’s immune cells to recognize and attack cancer cells. If the treatment worked, it would mean Sideris might not need surgery. “They told me it was all experimental—'Are you okay with that?' I said, 'Sign me up,'” says Sideris.