The unexpected result of a cancer study: remission in every patient

It was a small study, just 18 patients with rectal cancer, each taking the same drug.

But the results were amazing. The cancer disappeared in every single patient, undetectable by physical examination, endoscopy, PET scans, or MRI scans.

dr Luis A. Diaz Jr. of Memorial Sloan Kettering Cancer Center, an author of an article published Sunday in the New England Journal of Medicine describing the findings sponsored by pharmaceutical company GlaxoSmithKline, said he is not aware of any other study into the one treatment has completely eradicated a cancer in every patient.

“I believe this is the first time in the history of cancer,” said Dr. Diaz.

dr Alan P. Venook, a colorectal cancer specialist at the University of California, San Francisco, who was not involved in the study, said he also thinks this is a first.

A complete remission in every single patient is “outrageous,” he said.

These patients with rectal cancer had to endure grueling treatments — chemotherapy, radiation, and most likely life-altering surgeries that could result in intestinal, urinary, and sexual dysfunction. Some would need colostomy bags.

They took part in the study thinking that they would end up undergoing these procedures because nobody really expected their tumors to go away.

But they got a surprise: no further treatment was necessary.

“There were many tears of joy,” said Dr. Andrea Cercek, an oncologist at Memorial Sloan Kettering Cancer Center and co-author of the paper presented Sunday at the American Society of Clinical Oncology annual meeting.

Another surprise, added Dr. Venook added was that none of the patients had clinically significant complications.

On average, one in five patients has some type of side effect to medications like the one the patients were taking, dostarlimab, known as checkpoint inhibitors. The drug was given every three weeks for six months and cost about $11,000 per dose. It unmasks cancer cells and allows the immune system to identify and destroy them.

While most side effects are easily managed, 3 to 5 percent of patients taking checkpoint inhibitors have more serious complications, in some cases leading to muscle weakness and difficulty swallowing and chewing.

The lack of significant side effects, said Dr. Venook, meaning “either they haven’t treated enough patients, or somehow these cancers are just different.”

In an editorial accompanying the newspaper, Dr. Hanna K. Sanoff of the University of North Carolina’s Lineberger Comprehensive Cancer Center, who was not involved in the study, said it was “small but compelling”. However, she added that it was not clear whether the patients were cured.

“Very little is known about the time it takes to find out if a complete clinical response to dostarlimab is equivalent to a cure,” said Dr. Sanoff in the editorial.

dr Kimmie Ng, a colorectal cancer expert at Harvard Medical School, said that while the findings were “remarkable” and “unprecedented,” they needed to be replicated.

The inspiration for the rectal cancer study came from a clinical study that Dr. Diaz led in 2017 and funded by drugmaker Merck. It included 86 people with metastatic cancer that originated in different parts of their bodies. But all cancers shared a gene mutation that prevented cells from repairing damage to DNA. These mutations occur in 4 percent of all cancer patients.

Patients in this study took a Merck checkpoint inhibitor, pembrolizumab, for up to two years. The tumors shrank or stabilized in about a third to half of the patients, and they lived longer. The tumors disappeared in 10 percent of the study participants.

This prompted Dr. Cercek and Dr. Diaz on the question: What would happen if the drug was used much earlier in the disease process, before the cancer could spread?

They decided to study patients with locally advanced rectal cancer – tumors that had spread to the rectum and sometimes to the lymph nodes but not to other organs. dr Cercek had found that chemotherapy didn’t help a subset of patients who had the same mutations that affected patients in the 2017 study. Instead of shrinking during treatment, her rectal tumors grew.

Perhaps, argued Dr. Cercek and Dr. Diaz, immunotherapy with a checkpoint inhibitor would allow such patients to avoid chemotherapy, radiation and surgery.

dr Diaz asked companies that make checkpoint inhibitors if they would sponsor a small study. They declined because the process was too risky. he and dr Cercek wanted to give the drug to patients who could be cured with standard treatments. What the researchers suggested could lead to the cancers growing past the point where they could be cured.

“It’s very difficult to change the standard of care,” said Dr. Diaz. “The entire standard supply machinery wants to carry out the operation.”

Eventually, a small biotechnology company, Tesaro, agreed to sponsor the study. Tesaro was bought by GlaxoSmithKline and Dr. Diaz said he needed to remind the larger company that they were conducting the study — company executives all but forgot about the small study.

Her first patient was Sascha Roth, then 38. She first noticed rectal bleeding in 2018, but was otherwise fine — she’s a runner and helps run a furniture store in Bethesda, Maryland.

During a sigmoidoscopy, she recalled her gastroenterologist saying, “Oh no. I was not expect!”

The doctor called Ms. Roth the next day. He had the tumor biopsied. “It’s definitely cancer,” he told her.

“I’m completely melted down,” she said.

She was soon to start chemotherapy at Georgetown University, but a friend had insisted that she see Dr. Philip Paty at Memorial Sloan Kettering. dr Paty told her he was almost certain her cancer contained the mutation that made it unlikely to respond well to chemotherapy. However, it turned out that Ms. Roth was eligible to participate in the clinical study. If she had started chemotherapy, it wouldn’t have been her.

Not expecting a full response to dostarlimab, Ms. Roth had planned to move to New York after the study was complete for radiation, chemotherapy and possibly surgery. To preserve her fertility after the anticipated radiation treatment, her ovaries were removed and placed back under her ribs.

After the trial, Dr. Cercek the message.

“We looked at your scans,” she said. “There is absolutely no cancer.” She needed no further treatment.

“I told my family about it,” Ms. Roth said. “You didn’t believe me.”

But two years later, she still has no sign of cancer.