Ignacio Melero
Professor of Immunology at the University of Navarra, CIMA researcher and co-director of the Department of Immunology and Immunotherapy at the Clínica Universidad de Navarra.
This is an excellent experimental study using mouse tumor organoids implanted in the colon to metastasize to the liver. Interesting observations are made about malignant cells capable of nesting and thriving in the liver. In the final part, micrometastases are analyzed, and it is found that these micrometastases are sensitive to immunotherapy, as they have not yet formed an immunosuppressive environment to protect them.
This is an experimental study in an animal model. It advocates clinical trials in which preoperative immunotherapy is applied to colon cancer patients, especially those at high risk of having micrometastases. We do not know whether these findings will be confirmed and what the risk-benefit balance of immunotherapy will be. What we already know from recent publications is that preoperative immunotherapy in the subgroup of colon cancer patients with damage to the DNA repair mechanisms (approximately 15-20% of cases) frequently results in the disappearance of tumor cells in the surgical specimen.
As for the most important limitations, there would be the adverse effects of the combination of checkpoint inhibitors [immune checkpoint inhibitors]. Although it is a very interesting model, it may not faithfully reflect the immunology of micrometastases in patients.