[Two Cases of Achieving a Pathological Complete Response via Hepatic Arterial Infusion Chemotherapy for Liver-Limited and Unresectable Liver Metastases from Colorectal Cancer with RAS Mutations].

We had 2 cases of liver-limited and unresectable liver metastases from colorectal cancer with RAS mutations. These patients received hepatic arterial infusion chemotherapy(HAI), finally achieving pCR. Case 1 was a 76-year-old female with rectosigmoid cancer and multiple liver metastases. We underwent anterior resection for primary lesion. After surgery, the patient had received first-line and second-line systemic chemotherapy for the multiple liver metastases. The patient achieved SD and had Grade 3 neutropenia. We then performed HAI as third-line chemotherapy and we therefore underwent hepatectomy. The results of the pathological examination after hepatectomy pCR and is currently alive without cancer recurrence for 61 months. Case 2 was a 53-year-old male with sigmoid colon cancer and multiple liver metastases. We underwent sigmoidectomy with laparoscopic assistance. Three months after surgery, we underwent resection of the lateral segment of the liver under laparoscopy. This patient had cancer recurrence in the remnant liver at 6 months after surgery and had received first-line systemic chemotherapy. The patient had Grade 3 neutropenia after 1 course of chemotherapy and showed no improvement. We then performed HAI as second-line chemotherapy, and we therefore underwent hepatectomy. The results of the pathological examination after hepatectomy were pCR and he is currently alive without cancer recurrence for 30 months.