Received grant in 2025 

DCCC has funded 185,000 DKK to this project. 

Immunotherapy have been an immense breakthrough in the treatment of patients with solid tumors. However, most patients with colon cancer are refractory to immunotherapy, except patients with microsatellite instability-high (MSI-H) or mismatch repair deficient (dMMR). 

Patients with dMMR colon cancer accounts for around 15%. dMMR tumors are characterized by high mutational burden and high degree of tumor-infiltrating lymphocytes. Thus, the tumors are sensitive to immunotherapy such as pembrolizumab. 

In 2021, the investigators behind this study received funding for a study demonstrating that a single dose of neoadjuvant pembrolizumab is both safe and effective in patients with stage I–III dMMR colonrectal cancer. The results suggest that the treatment may reduce the need for surgery and form the basis for organ-sparing treatment strategies. 

This study builds on these results and aims to investigate the efficacy and safety of neoadjuvant pembrolizumab in patients with dMMR colon cancer who have been referred for surgery. Patients who respond to the treatment will be offered an organ-sparing watch-and-wait strategy. 

In addition, the study will explore factors associated with treatment response, with the aim of identifying predictive biomarkers that can help guide personalised treatment decisions. 

As part of the study preparation, the group will organise two national workshops to ensure clinical consensus and consistent implementation. The first workshop will focus on the study protocol and operational structure, while the second will provide training in the assessment of tumour response. 

The study is expected to pave the way for a new organ-preserving treatment strategy for patients with dMMR colon cancer. This approach could reduce the need for surgery, minimise treatment-related side effects, and improve patients’ quality of life. 

Multidisciplinary organisation  

This study builds on the previous DCCC-supported initiative:

Neoadjuvant immunotherapy in dMMR colorectal cancer

-and is and is anchored within the:
Danish Colorectal Cancer Group (DCCG). 

Project stakeholders 

  • Camilla Qvortrup, Consultant, Department of Oncology, Rigshospitalet  
  • Ismail Gögenur, Professor, Center for Surgical Science, Department of Surgery, Zealand University Hospital. Primary contact, mail: igo@regionsjælland.dk  
  • Tobias Freyberg Justesen, MD, Department of Surgery, Zealand University Hospital 
  • Per Pfeiffer, Professor, Consultant, Department of Oncology, Odense University Hospital 
  • Laurids Østergaard Poulsen, Head Consultant, PhD, Department of Oncology, Aalborg University Hospital 
  • Peter-Martin Krarup, Consultant, Abdominalabnocenter K, Bispebjerg Hospital 
  • Jakob Vasehus Schou, Head Consultant, Department of Oncology, Herlev & Gentofte Hospital 
  • Torben Frøstrup Hansen, Professor, Research Lead, Department of Oncology, Vejle Hospital 
  • Pernille Wolder Born, MD, Department of Surgery, Hvidovre Hospital