3061 Solitary Brain Metastasis as the Initial Manifestation of Descending Colon Cancer

Abstract

INTRODUCTION: Brain metastasis of colon cancer is often accompanied by metastasis to other organs, and the prognosis is poor. However, long-term survival is reported in some solitary brain metastasis cases. We present a case of descending colon cancer with brain metastasis and relatively long survival after surgery. CASE DESCRIPTION/METHODS: Having suffered from amnesia, dysgeusia and headache for 2 weeks, a 58-year-old woman visited a nearby hospital. With a projected tumor in the right occipital brain, she was referred and then admitted to our hospital. A CT scan showed a descending colon tumor, while the PET/CT scan showed fluid accumulation in a right brain tumor and a descending colon lesion. An open resection was indicated to remove a 35 × 40 mm brain tumor, followed by colonoscopy 7 days later, with the scope unable to pass through the entire circumferential tumor. Histopathologic diagnosis confirmed moderately and highly differentiated adenocarcinoma of the colon and moderately differentiated adenocarcinoma of the brain. This indicated colon cancer spread to the brain. The patient was treated with total brain irradiation of 30 Gy/10 times. With no evident distant metastases, she underwent left hemicolectomy 27 days after the brain surgery, removing a nearly 2-cm omental nodule neighboring the tumor. The serosa showed that the main lesion (a non-exposed type-2 tumor of 40 × 50 mm) retracted surrounding tissue. It mainly comprised moderately differentiated adenocarcinoma and poorly differentiated adenocarcinoma at the infiltration tip. Vascular invasion into the subserosa (SS) was observed with five lymph node metastases (N2) and adenocarcinoma in omental nodules (P1). Experiencing a good postoperative course and after treatment with chemotherapy, the patient survived 20 months after the brain surgery without evident brain metastasis relapse, despite liver metastasis 7 months after surgery. DISCUSSION: Although rare (0.4-1.8%), brain metastases have a high metastasis rate (82%), resulting in a low one-year survival rate after diagnosis (16%) and poor prognosis. However, long-term survival is frequently reported in cases with solitary brain metastasis. Resection is indicated for brain metastasis of colon cancer when life prognosis is longer than several months; excision causes no serious neurological symptoms; and brain metastasis spreads to no other organs or is well controlled. Surgical treatment, therefore, was considered suitable for our patient.