Purpose: To clarify the relative frequency of various histopathological primary spinal cord tumors and their features in Japanese people and to compare this data with other reports.
Methods: Primary spinal cord tumor surgical cases from 2000 to 2009, which were registered in our affiliated hospital database were collected. We examined age at surgery, sex, anatomical location, vertebral level of the tumor, and pathological diagnosis in each case.
Results: Of the 678 patients in our study, 377 patients (55.6 %) were males and 301 patients (44.4 %) were females (male/female ratio 1.25). The mean age at surgery was 52.4 years. Of these tumors, 123 cases (18.1 %) were intramedullary, 371 cases (54.7 %) were intradural extramedullary, 28 cases (4.1 %) were epidural, and 155 cases (22.9 %) were dumbbell tumors. The pathological diagnoses included 388 schwannomas (57.2 %), 79 meningiomas (11.6 %), 54 ependymomas (8.0 %), 27 hemangiomas (4.0 %), 23 hemangioblastomas (3.4 %), 23 neurofibromas (3.4 %), and 9 astrocytomas (1.3 %). The male/female ratios for schwannomas, meningiomas, ependymomas, hemangiomas, hemangioblastomas, neurofibromas, malignant lymphomas, and lipomas are 1.4, 0.34, 1.3, 1.5, 2.3, 1.3, 2.7 and 2.3, respectively.
Conclusion: This is the first published research in English on the epidemiology of primary spinal cord tumors in Japanese people. Similar to other reports from Asian countries, our data indicates a higher male/female ratio overall for spinal cord tumors, a higher proportion of nerve sheath cell tumors, and a lower proportion of meningiomas and neuroepithelial tumors compared to reports from non-Asian countries. Data in the current study represent the characteristics of primary spinal cord tumors in Asian countries.