Abstract
BACKGROUND: Retroperitoneal schwannomas are rare. CASE PRESENTATION: We here report a case of 64-year-old woman who was referred to her local hospital for abdominal pain and found to have a palpable tumor. Computed tomography (CT) and colonoscopy revealed a combination of liver and colon lesions and colon cancer with a large liver metastasis was suspected. After neoadjuvant chemotherapy had proved ineffective for her presumed liver metastasis, the patient was referred to our hospital where we performed a simultaneous right hemicolectomy and extended left hepatic lobectomy. The pathological diagnoses were a colonic adenocarcinoma and retroperitoneal schwannoma immediately adjacent to the liver. CONCLUSIONS: Although liver metastasis should be the first provisional diagnosis in patients with advanced colon cancer, retroperitoneal schwannoma should also be suspected in the differential diagnosis of possible liver lesions.