Turning the Immune System Against Colon Cancer

Patient Ryan D’Cunha was devastated when he learned a genetic mutation resulted in cancer. But he found hope at USC.

December 04, 2017 Amber Dance

The symptoms began with a persistent stomachache. Indigestion, Ryan D’Cunha thought. Maybe acid reflux. Doctors tested for gallstones and prescribed a fiber-heavy diet and antibiotics.

But the pain worsened, interfering with his work as a campus supervisor at an elementary school in Riverside, California. He could barely eat. Students asked, “Mr. D, are you OK?” On Christmas Day in 2016, worried family members noticed how much weight he had lost, and took him to the emergency room. A CT scan identified tumors in his colon and liver.

The tumors—at more than 3 inches across—were too big to cut out. His oncologist at the hospital suggested standard chemotherapy to shrink them. When D’Cunha sought a second opinion, she sent him to oncologist Heinz-Josef Lenz at USC Norris Comprehensive Cancer Center.

At age 40, he considers himself blessed to have found USC, Lenz and the trial.

Lenz told D’Cunha that with his type of cancer —on the right side of his colon—chemotherapy probably wouldn’t work well. Instead, Lenz sent D’Cunha’s tumor tissue for molecular testing to find better therapies in the form of clinical trials.

Tests showed his cancer was caused by a mutation in the MLH1 gene. D’Cunha was devastated to learn the cause of his cancer was in his DNA and inherited, meaning his two sisters and three children might also carry the gene. But at the same time, he was thrilled to receive personalized treatment best suited for his disease.

“I was stoked,” says D’Cunha (who notes he picks up language from kids at his job). He was also pleased to participate in research that could lead to treatments or a cure for future patients.

D’Cunha received a combination of two immunotherapies, nivolumab and ipilimumab. Called immune checkpoint inhibitors, they help turn on the body’s own immune response to the cancer. “Giving immunotherapy in newly diagnosed metastatic colon cancer is revolutionary,” says Lenz, who notes that it was the first such clinical trial in the world. Otherwise, D’Cunha would have received a combination of chemotherapies, which can cause significant side effects.

With support from family and friends, D’Cunha maintained a positive outlook throughout treatment. At age 40, he considers himself blessed to have found USC, Lenz and the trial. “Everybody there has taken really good care of me,” he says.

After seven months of treatment, Lenz offered D’Cunha good news: The tumors were small enough for surgery aimed at curing the cancer. He underwent the operation in September, and hopes the cancer will stay away. D’Cunha plans to earn a teaching certificate, and also wants to find a way to bring his positive philosophy to other cancer patients, perhaps through volunteering or starting a nonprofit.