LAUSR

To the editor, We thank Dr Treasure for his interest and critical appraisal of our publication entitled “Curative‐intent treatment of recurrent colorectal liver metastases: a comparison between ablation and resection.” In the letter to the editor, Dr Treasure points out that treating lung metastases from colorectal cancer, either with surgery or IGTA, did not bring evidence of a real survival benefit compared to surveillance. Indeed, results from the PulMiCC randomized controlled trial “indicates that survival is predominantly a feature of expert selection of those with a better prognosis plus the effect of guaranteed time bias.” IGTA has gained increasing interest in the recent years and is a much less invasive method for treating lung metastases, especially in altered patients that could not undergo surgery. Our main objective was to show that IGTA was as efficient, technically and oncologically, as surgery. Our results show that both techniques are comparable, in terms of morbidity and survival. However, we did not have a control group of unoperated patients whose outcomes could be compared with our two group, therefore we could not discuss the real survival benefit of treating lung metastases. However, even the PuLMiCC trial, which is the only one exploring the survival benefit of treating lung metastases compared to surveillance, was hardly able to bring significant evidence in this matter. Eventually, even though our work is only retrospective, our results confirmed that using IGTA was a viable alternative option to surgery in the treatment of lung metastases from colorectal cancer. Despite the survival benefit of local treatment has not been proven rigorously, it is likely that local treatment (surgery, IGTA, radiotherapy) is useful in some patient with oligometastatic disease. Increase knowledge in new and nonclinical prognostic factors, such as genomic, epigenetic, and immunologic features, will help us in selecting the patients who will have a survival benefit after local treatment. Furthermore, with progress in chemotherapy regimen, patients with colorectal liver metastases are treated with several lines of chemotherapy and local treatment can sometimes offer patients time without any systemic treatment, which is essential when dealing with a chronic disease. Even though there is no survival benefit with local treatment, the next step for the oncological community is to evaluate the quality of life with systemic treatment versus local treatment.