This year at ESMO, several exciting studies highlighted new ways to personalise treatment and improve outcomes for those diagnosed with colorectal cancer.

1. Personalising chemotherapy in stage III colon cancer – DYNAMIC-III trial
Researchers assessed whether ctDNA (circulating tumour DNA analysed via a blood test) could help decide who really needs chemotherapy after surgery. Patients whose ctDNA was negative could safely receive less chemotherapy. This approach reduced side effects, hospital stays, and exposure to the drug oxaliplatin, without significantly affecting the risk of cancer returning—especially in patients with lower-risk tumours.

Key takeaway: For some stage III colon cancer patients, ctDNA can help doctors safely give less chemotherapy, reducing side effects without increasing the risk of the cancer coming back—especially for those with lower-risk tumours.

2. Immunotherapy in MSI-H/dMMR metastatic colorectal cancer – CheckMate 8HW trial
This study confirmed that combining nivolumab and ipilimumab (both immunotherapy drugs that help the immune system attack cancer) is more effective than nivolumab alone in patients with certain genetic changes, such as microsatellite instability-high (MSI-H) or mismatch repair-deficient (dMMR) metastatic colorectal cancer. The combination improved survival and tumour response with manageable side effects.

Key takeaway: Nivolumab plus ipilimumab is now a standard treatment option for MSI-H/dMMR metastatic colorectal cancer.

3. New options for microsatellite-stable colorectal cancer – STELLAR-303 trial
For patients with microsatellite-stable (MSS) metastatic colorectal cancer who had already received other treatments, the combination of zanzalintinib and atezolizumab improved both survival and disease control compared with regorafenib, with manageable side effects.

Key takeaway: This new combination may offer an effective treatment option for previously treated MSS colorectal cancer.

Author:

Natasha Muench