New Cancer Treatment Harnesses Immune System to Tackle Several Types

New Immune Treatment Shows Promise in Helping Cancer Patients Avoid Surgery

At the American Association for Cancer Research's annual meeting, researchers unveiled promising early results from a groundbreaking study aimed at helping cancer patients bypass surgery.

Published simultaneously in the New England Journal of Medicine, the study reveals that 92% of patients who underwent an immune-based treatment—without surgery—showed no detectable signs of cancer after two years. This treatment harnesses the body’s immune system to shrink tumors, offering a potential alternative to traditional surgery, which is typically the standard approach for these patients.

One of the participants, 71-year-old Maureen Sideris, was diagnosed with gastroesophageal junction cancer in 2022 after struggling with swallowing and digestion. Initially, her surgeon recommended surgery, followed by chemotherapy and radiation. But after learning about a study led by Dr. Andrea Cercek at Memorial Sloan Kettering Cancer Center, Sideris agreed to participate in a trial using a checkpoint inhibitor—a newer treatment that boosts the immune system to target cancer cells. If successful, this approach could eliminate the need for surgery.

Although Dr. Cercek had not previously treated patients with Sideris' type of cancer using this method, her 2024 study on rectal cancer showed encouraging results: all 42 patients treated with the checkpoint inhibitor dostarlimab became cancer-free, with some remaining in remission for years. Now, Dr. Cercek is testing whether this method could benefit patients with other cancers, including esophageal, stomach, and gastroesophageal junction cancers, like Sideris'.

In the latest study, 64% of patients with non-rectal cancers showed no signs of disease after one year. Combining both rectal and non-rectal cases, 92% remained free from cancer recurrence after two years. Even patients who did experience a recurrence saw a reduction in tumor size or number.

“The bottom line is that everyone benefited,” Dr. Cercek says. “No one was harmed. This treatment led to complete responses, tumor shrinkage, and improved quality of life.”

Immunotherapy offers a less invasive alternative to traditional treatments like surgery, chemotherapy, and radiation, though it comes with potential side effects like fatigue and skin rashes. For Sideris, the treatment’s monthly 45-minute infusion was “the easiest part of the whole thing,” she says, adding that she continues regular imaging to monitor for any signs of recurrence.

Dr. Cercek views this as a major step forward in using immunotherapy to replace surgery in early-stage cancers. She plans to follow up with patients like Sideris to see if the benefits translate into longer survival and is also studying why some patients didn’t respond to the treatment to improve outcomes.

Encouraged by these results, the National Comprehensive Cancer Network has already included dostarlimab in their treatment guidelines for cancers with the specific genetic mutations studied by Dr. Cercek. The FDA has also granted the drug fast track designation for these types of cancers, including endometrial cancer.

Dr. Cercek remains hopeful that this treatment could be effective for other genetically altered tumors. She is especially encouraged by the fact that many of the patients in this study had cancers that had spread to lymph nodes, not just early-stage tumors. “We think that as long as there’s no distant spread, or metastasis, patients could benefit,” she says.