Chronic Subdural Hematoma due to Dural Metastasis: Demonstration of Adenocarcinoma Cell Nests in the Fluid: Case Report

A 43-year-old male developed headache, restlessness, urinary incontinence, and right hemiparesis 15 months after partial gastrectomy for adenocarcinoma of the stomach. Computed tomography (CT) scan on admission showed a crescent-shaped low-density area in the right frontotemporal region and a midline shift to the left. Under the diagnosis of chronic subdural hematoma, burr hole irrigation was performed. Following the procedure, the patient became lucid and the hemiparesis disappeared. However, 7 days later the disturbance of consciousness and right hemiparesis recurred. CT scan revealed re-retention, and irrigation was repeated. Nests of adenocarcinoma cells were found in the xanthochromic fluid obtained during the procedure and the diagnosis was subdural hematoma due to dural metastasis. The patient died 8 days later. The autopsy revealed dural metastatic tumor and a subdural hematoma over the right hemisphere. Histological examination disclosed intravascular tumor cells in the inner and outer layers of the dura, extending to the hematoma cavity. Twenty-eight similar cases were reported in the literature. In the present case, there was probably sudden, rapid growth and sloughing of tumor cells at the metastatic focus in the dura at the end stage of cancer. It is presumed that the hematoma developed secondarily to a bleeding tendency due to bone marrow metastasis.