We analyzed the clinicopathological factors in two cases of local recurrence after a disease-free interval (DFI) of more than 12 months following microwave coagulation therapy (MCT) for liver metastases from colorectal cancer. Case 1: A local recurrence was diagnosed at 14 months after MCT for a liver metastasis of 20 mm in diameter from rectal cancer. Following liver resection, the patient remains alive without recurrence at 9 months. Case 2: A local recurrence was diagnosed at 19 months after MCT for a liver metastasis of 20 mm in diameter from rectal cancer. After MCT, the patient remains alive without recurrence at 36 months.
Conclusion: We treated two patients with local recurrence who have more than 12 months' DFI after MCT for liver metastases from colorectal cancer. MCT or liver resection was performed as a curative therapy in these cases. Caution is recommended for local recurrence at more than 12 months after MCT for liver metastases from colorectal cancer.