[Colorectal carcinoma with hemiparesis due to isolated brain metastases as an initial symptom - a case report]

We present a rare case of colorectal carcinoma in which hemiparesis was the initial symptom. A 75-year-old woman presented with incomplete left-sided hemiparesis. Brain magnetic resonance imaging(MRI)revealed a 13-mm mass in the right frontal lobe; the mass was resected via craniotomy. Pathological findings, which included the results of immunohistochemical analysis, indicated brain metastasis from colorectal cancer. Colonoscopy revealed advanced colon cancer in the ascending colon, and computed tomography(CT)did not reveal any extracranial metastases. Left-sided hemicolectomy was performed. Whole-brain radiotherapy was scheduled, but before initiation of the therapy, metastases were detected in the neck lymph node and right arm skin, and the brain metastases relapsed. The relapsed brain metastatic lesions were resected, and radiotherapy was administered to the whole brain and the severely painful site of skin metastasis. However, the patient died 201 days after presentation. Historically, systemic chemotherapy was considered ineffective for metastatic brain tumor, and the standard treatments for brain metastasis were surgery and radiotherapy. Although recent advances in systemic chemotherapy for colorectal cancer have resulted in improved patient survival, patients with brain metastases from colorectal cancer still have a poor prognosis. Modern chemotherapeutic agents, including molecularly targeted agents such as bevacizumab, should be validated for the management of brain metastases.