Conversion surgery by hand-assisted laparoscopic surgery following chemotherapy for rectal cancer with H3 liver metastases: a case report

Background: Recent advancements in molecularly targeted chemotherapy for stage IV colorectal cancer have enabled the possibility of complete resection in primary colorectal cancer, which often involves distant liver or lung metastases, by aggressive surgical resection followed by multi-combination chemotherapy. Case description: A 73-year-old man treated previously for hyperuricemia, hypertension, and a dissecting abdominal aortic aneurysm was referred to us after an incidental finding of multiple liver masses on abdominal ultrasound during follow-up for the aneurysm. A detailed examination by contrast-enhanced computed tomography revealed a ring-enhancing mass larger than 5 cm in diameter in segment 3 of the liver and more than 6 low-density areas with total diameter of 1 to 2 cm in both lobes. A barium enema examination revealed a Borrmann type 2 lesion covering two-thirds of the circumference of the colon, with a 5-cm major axis in the rectosigmoid colon. Biopsy revealed a well-differentiated adenocarcinoma. The patient was diagnosed with stage IV rectal cancer. Because there was no intestinal obstruction, we administered 9 cycles of bevacizumab with capecitabine and oxaliplatin as chemotherapy. Subsequent diagnostic imaging revealed the metastatic lesions in liver segment 3 had reduced to 2 low-density areas with a diameter of 8 mm, and the other hepatic metastases had disappeared; the main tumor had flattened and shrunk. Therefore, we used hand-assisted laparoscopic surgery (HALS) to perform anterior resection of the rectosigmoid colon and partial resection of liver segment 3 as conversion therapy. The patient was discharged 10 days after surgery. The rectal lesion was a well-differentiated adenocarcinoma with a depth of invasion of p-MP and a spread of L0, V0, and pN0. The partial hepatectomy did not indicate viable cancer cells; only necrotic, lysed tissue was observed. Postoperative chemotherapy involved 4 cycles of bevacizumab with capecitabine and oxaliplatin. At more than 42 months postoperatively, no metastasis or recurrence has been observed. Conclusions: This rare case demonstrates that conversion surgery can be a viable option following systemic chemotherapy in patients with advanced colon cancer and H3 liver metastases.