Case Report: Remarkable response to savolitinib plus chemotherapy and bevacizumab in second-line treatment of MET amplified colon cancer with liver metastasis.

Metastatic colorectal cancer (mCRC) is associated with poor prognosis and low survival rates, with acquired resistance limiting the durability of standard therapies. Mesenchymal-epithelial transition factor (MET) amplification is a rare but potentially actionable molecular alteration that has been implicated in treatment resistance, while clinical evidence supporting MET-directed combination therapy in mCRC remains limited. We report a rare case of a young patient with KRAS/NRAS/BRAF wild-type descending colon cancer with liver metastases and de novo MET amplification detected in the pretreatment primary tumor. After achieving stable disease with second-line FOLFIRI plus bevacizumab, savolitinib, a highly selective MET tyrosine kinase inhibitor (TKI), was added to the ongoing regimen. The patient subsequently achieved marked radiologic and pathological regression during combination treatment, suggesting a possible additive contribution of MET inhibition. Our findings suggest that the addition of savolitinib to standard chemotherapy and a VEGF inhibitor may have contributed additional antitumor activity in this patient with MET-amplified mCRC. However, the independent contribution of savolitinib cannot be determined, and this observation should be regarded as hypothesis-generating and warrants validation in prospective studies.