[Intramedullary metastasis of small cell lung cancer]

A 64-year-old man complaining of hoarseness received a diagnosis of small cell lung cancer (T4 N3 M1, Stage IV) in May 1997. He responded well to chemotherapy and radiotherapy, and afterward underwent brain irradiation for prophylactic purposes. However, on Nov. 27 the patient experienced lumbar pain and numbness in his left leg. and was admitted to our hospital on Dec. 2 because his symptoms deteriorated to palsy of the left leg. Brain computed tomographic scans and lumbar magnetic resonance imaging (MRI) were normal, as was serum pro-GRP. Palsy developed in both legs 3 days later. T2 weighted MRI revealed high intensity within the spinal cord at the level between Th 9 and Th 11, and T1 weighted MRI showed heterogeneous low intensity at the same levels. In addition, Gd-DTPA enhanced T1 weighted images disclosed high intensity in the spinal cord at the Th 10 level. Although 3 spinal taps were all cytologically negative for malignancy, the high pro-GRP titer (1,400 pg/ml) suggested the presence of a carcinomatous lesion. At autopsy, cross sections of the spinal cord revealed the longitudinal extension of a tumor 11 cm in length. Microscopic findings indicated that the tumor was a metastasis of the patient's small cell carcinoma. To our knowledge, this report was the first to histologically examine a case of intramedullary metastasis of small cell lung cancer.