What if surgery was no longer inevitable?

It is a therapeutic feat that could revolutionize the management of certain cancers by avoiding heavy and risky interventions, such as organ ablations. At the Memorial Sloan-Kettering Cancer Center (MSKCC), in New York, a team of researchers recently tested an immunotherapy treatment alone, without surgery or chemotherapy, in patients with tumors with mutation in DNA repair genes. The medication administered, the Dostarlimab, gave spectacular results, according to their work published in The New England Journal of Medicine and relayed by The New York Times.

An effective alternative to surgery

Of the 103 patients included in the clinical trial, all carrying tumors called immunotherapy, scientists have chosen to use only the Dostarlimab, a monoclonal antibody. “Twenty or thirty years earlier, the idea of ​​dealing with large tumors without operation would have noted science fiction”testifies Dr. Bert Vogelstein (Johns Hopkins University). And yet, the results are there: in 49 patients with rectum cancer, tumors have disappeared completely, without recurrence five years later. Same observation for 35 out of 54 patients with other cancers (stomach, esophagus, liver, prostate, uterus …). In total, “80 % of patients were successfully treated by immunotherapy alone”summarizes an MSKCC press release.

Among the volunteers, Maureen Sideris, 71, discovered his esophagus-estomac junction cancer in 2022. He was offered heavy surgery, radiotherapy and chemotherapy. But his genetic profile allowed him to integrate the test. “From January, the tumor had disappeared, she recalls. I have hormonal treatment for my adrenal glands, but it is a low price to pay to avoid surgery. “

A key genetic explanation

If the treatment was so effective, it is because the tumors in question showed repair deficiencies for DNA mesappars – present in 2 to 3 % of cancers. Namely mutations preventing correct DNA repair, which causes an accumulation of abnormal proteins. The immune system could destroy them, but the tumors erect a “shield” that block the attacks. Immunotherapy acts by piercing this shield, allowing natural defenses to do their work.

For Dr. Michael Overman (MD Anderson Cancer Center), this approach is “So logical that we should put it into practice”. But the cost remains an obstacle: around 11,000 dollars per dose (9,700 euros), with nine infusions required over six months. For the moment, the Dostarlimab is reimbursed in certain cases (especially for cancers of the uterus with mutation of DNA repair genes), but not for all types of tumors.