Nat Med: Clinical trials show preoperative immunotherapy is effective for colon cancer patients

14, 2020 /PRNewswire
2020 /
Bio-Valley BIOON/--- In an innovative Phase II
clinical trial called NICHE, researchers from the Netherlands Cancer Institute found that patients with colon cancer but not distant metastasis can benefit from short-term immunotherapy while waiting for surgery because it can cause tumor to shrink or clear significantly in a very short period of time The patient's own immune cells remove cancer cells In patients with colon cancer microsatellite instability (microatellite intable, MSI), 100% benefited from immunotherapy, while 25% of patients with colon cancer microsatellite stabilization subtypes (microatellite-table, MSS) benefited The findings were published online April 6, 2020 in the journal Nature Medicine under the title "Neoadjuvant adetentitled lead to repone in MMR-farand and MMR-deficient early-tage colon cancer" The paper is written by Myriam Chalabi and Emile E Voet of the Netherlands Cancer Institute Killer T cells surround cancer cells, pictured from NIH pre-surgical immunotherapy called neoadjuvant immunotherapy, which is designed to prevent tumor recurrence or metastasis, and for larger tumors, it is easier to perform surgery The main idea is to familiarize the immune system with all tumor variants before the tumor is removed, thus making it better able to respond Colon cancer is the second type of cancer after melanoma In the new study, the researchers demonstrated the effectiveness of new immunotherapy in colon cancer Research on the of other types of tumors is still ongoing Forty patients with these two colon cancer subtypes participated in the NICHE study Twenty of these patients had colon cancer MSI subtypes, which means that tumors prone to mutations, leading to hundreds of mutations Of all non-metastatic colon cancer patients, 15% had colon cancer MSI subtypes Immunotherapy was effective in all 20 patients with colon cancer MSI subtype "The response rate was good for this group of patients," Chalabi said However, the 100% cure rate is unprecedented You don't dare expect it to have such a good effect "These patients underwent surgery about 4 weeks after the first intravenous immunotherapy drug In this short period of time, the vast majority of tumors have been completely or almost completely removed "We can clearly see where tumor , but the patient's own immune cells have removed the cancer cells "Previous studies have shown that immunotherapy is effective for MSI subtypes of advanced metastatic colon cancer There is a good scientific explanation: the more new mutations in the tumor , the stronger its non-selfiness, which causes the immune system to respond colon cancer MSS subtype patients had a response rate of 25% in the NICHE study, and the remaining 20 patients were colon cancer MSS subtypes This colon cancer subtype does not respond well to immunotherapy To the researchers' surprise, they found that 25 percent of the patients in the group also responded well This is a promising outcome, considering that 85% of non-metastatic colon cancer patients have this subtype of colon cancer The researchers tried to explain this surprisingly high response rate in the colon cancer MSS subtype in the lab First of all, it's not easy "We looked at all the common suspects, but they weren't the cause," Chalabi said We don't see the predictors like those in melanoma However, we did find a new biomarker If it is shown to be predictive in follow-up studies, it could provide an easy way to identify patients with colon msS subtypes who benefit from immunotherapy "An important additional advantage of the new complementary immunotherapy study is that they allow immunotherapy to be precise on the cancerous tissue that has been removed, depending on the patient's specific condition In this sense, as laboratory research and clinical practice become more integrated, new complementary immunotherapy is revolutionizing cancer research Ground-breaking new immunotherapy drug research, such as NICHE, has also had a significant impact on the research of oncologists surgeons The study depends on their trust: Are surgeons willing to accept waiting and uncertainty? "Our surgeons were very enthusiastic from the start, otherwise we wouldn't have been able to do this clinical trial ," Chalabi said "Therefore, the primary purpose of the NICHE study was to confirm that the operation was safe and scheduled and that there would be no more postoperative complications than expected--- Can surgery be saved? Like patients, the researchers were very pleased with the results of the NICHE study "The larger tumors shrink or completely clear within four weeks on average, which is a fantastic and unprecedented result," Chalabi said We've never seen a 100% response rate before The question some patients ask in the of clinical trials is whether surgery can be performed altogether Chalab cautions that this is premature because "even if we find out during the operation that tumor has disappeared, we can't know in advance who will react completely, even with the help of scanning technology." "So researchers need to find the answer to this question: How do they know as much as possible before surgery if the patient is responding completely?" "It's not easy to answer, but we're trying to figure it out "Once the the tumor completely or almost completely removed, how likely is it that the patient will still have metastasis?" "We think the risk is very low," Chalabi said We found this in the of melanoma But first, we need to treat and monitor patients before we can answer this question "As a result, the NICHE study will continue and the number of patients will increase." These patients need to be monitored for at least three years to see if they have not returned to the disease "It is only then that this new treatment can be considered standard," Chalabi said "At the same time, many new studies will be conducted in the laboratory with tumor samples from these patients The researchers will use advanced medical imaging and so-called liquid biopsy techniques to look for traces of tumor DNA in the blood (Bio Valley Bioon.com) Reference: 1.Myriam Chalabi et al.
Neoadjuvant adath lead to lenar one in MMR-far-fyand y MMR-deficient ei-tage colon cancer Nature Medicine, 2020, doi:10.1038/41591-020-0805-8.2 Immunotherapy prior to urge i in colon cancer
http://medicalxpre.com/new/2020-04-immunotherapy-prior-urgery-effective-colon.html