[A Patient Who Underwent Resection of Liver Metastases after Receiving Systemic Chemotherapy for Advanced Rectal Cancer and Multiple Liver Metastases].

The patient was a 52-year-old man who had a positive fecal occult-blood test on a medical check-upi n April 2015 and was referred to our hospital in June. Detailed preoperative examinations resulted in a diagnosis of cancer of the lower rectum, multiple liver metastases, and clinical Stage IV . A biopsy showed moderately differentiated tubular adenocarcinoma. All-RAS was wild type, and the patient was asymptomatic. Unresectable advanced rectal cancer was diagnosed, and the patient was scheduled to receive systemic chemotherapy. The patient received a total of 16 courses of combination chemotherapy with 5- fluorouracil, Leucovorin, and oxaliplatin(FOLFOX)plus panitumumab, starting in October 2015. In July 2016, Colonoscopy showed scar findings at the site of the primary rectal cancer lesion. A biopsy revealed no cancer cells. It was difficult to identify the primary lesion on computed tomography, and there was no evidence of clinically significant lymphadenopathy. Positronemission tomography and computed tomography showed shrinkage of the liver metastases, with no accumulation of tracer in the primary lesion or lymph nodes. The primary lesion had a clinical complete response(CR), and the metastatic lesions had a clinical partial response(PR). In October 2016, laparoscopic partial hepatectomy was performed to treat the liver metastases. Histologic examination showed that the liver metastases were from rectal cancer. It is currently under observation.