We report a 36-year-old woman with right hemiplegia, anosognosia, and rapidly deteriorating course. She was well until the end of January, 1995 when she had an onset of fever, sputum, and cough. A 5 x 5 tumor was found in her left lower lobe. She was admitted to the Pulmonary Medicine on May 24, 1995 when she was 36-year-old. General physical examination was unremarkable. Bone scintigraphy revealed increased uptake in the skull, sternum, right scapula, vertebrae, right femur, and in ribs. Cranial CT scan revealed a large mass lesion in the right frontal subcortical region with central low density and peripheral high density areas, and small low density lesions in the right thalamic area and in the right posterior frontal region; ring enhancement was observed in the latter two lesions. On the second day of admission, she noted left-sided weakness which improved by corticosteroid treatment. On June 17, there was a sudden onset of left hemiparesis and a neurologic consultation was asked. Upon neurologic examination, she appeared somnolent but could understand verbal commands. She showed constructional apraxia, neglect of the left hemisphere, and anosognosia. Cranial nerves were unremarkable. Motor-wise, she showed flaccid left hemiplegia. Deep tendon reflexes were exaggerated on the left and the plantar response was extensor bilaterally. Nuchal stiffness was noted. Her cranial CT scan on June 17 revealed enlargement of the right frontal mass lesion. The subsequent course was complicated by DIC and progressive worsening of her consciousness. On June 18, she was comatose and pupillary light reflex was lost. She developed Cheyne-Stokes respiration and expired on that evening. The patient was discussed in a neurological CPC, and the chief discussant arrived at the conclusion that the patient had a primary adenocarcinoma in the lung with multiple metastases including the brain. The fulminant terminal course was ascribed to hemorrhage within the tumor and subsequent central type of transtentorial herniation. Opinions were divided regarding the cause of hemorrhage; some participants thought hemorrhage was caused by DIC. Post-mortem examination revealed an adenocarcinoma arising at the S6 segment of the left lung with multiple organ metastases. In the brain, a huge hemorrhagic metastasis was found in the right frontal lobe and a non-hemorrhagic metastasis in the right thalamic region. Probably, the size of the metastases influenced the occurrence of hemorrhage. The direct cause of the death was transtentorial herniation.