2002 Volume 29 Issue 4 Pages 772-774
BackgroundThe correct incidence of brain tumors remains unknown in Japanese population, based on large number of individuals with brain check-up.
PurposeTo examine thh incidence of brain tumors in the retrospective study of brain check-up in PL Tokyo Health Care Center, Japan. We also evaluated whether multiphasic health tests, including physical and brain check-up, have benefits for the early diagnosis of brain tumors.
MethodWe analyzed 2, 312 participants who received brain and physical health check-up simultaneously between April 1, 2001 and January 31, 2002. Male was 1, 592 subjects and female was 720 subjects. Mean age was 53.5 (SD 11.0) years in all, 53.7 (SD 11.0) years in men, and 53.1 (SD 11.1) years in women. Among them, the first brain check-up was performed in total of 1, 343 (58.1%) subjects, 868 (54.4%) in men, and 475 (66.0%) in women. Brain check-up was produced by 1.5-tesla superconducting system (Stratis II, Hitachi Medical Co., Japan) . Conventional magnetic resonance imaging (MRI) and magnetic resonance angiography were studied in all sub-jects.
ResultsBrain tumors were seen in total of 16 subjects (10 men and 6 women) . The overall incidence was 0.69%, 0.63% in men and 0.83% in women. The mean age of subjects with tumors was 55.1 (SD 10.5) years in all, 55.1 (SD 13.0) years in men, and 55.0 (SD 5.5) years in women. The first study of brain check-up revealed brain tumors in 14 of 16 subjects (9 men and 5 women) . The overall inci-dence of tumors on the first brain check-up was 1.04%, 1.04% in men and 1.05% in women. The mean age was 54.7 (SD 10.9) years in total, 54.0 (SD 13.2) years in men, and 56.0 (SD 5.5) years in women. The results of self-questionnaire indicated that 14 of 16 subjects had no significant symptoms. The retrospective study supported that physical check-up showed no malignant tumors in other organs in all subjects with brain tumors. Primary brain tumors were diagnosed in all cases. Neuropathological diagnoses were confirmed in 10 subjects. The histological results indicated meningioma (1 man), pituitary adenoma (1 man and 2 women), glioma (1 man and 1 woman), neurinoma (1 man and 1 woman) and malignant lymphoma (1 man) . In two follow up subjects, meningioma was diagnosed by typical patterns of MRI. Benign lipoma (4 men) was diagnosed with fat-suppression MRI.
ConclusionOur studies indicate that the incidence of primary brain tumors is 690 per 100, 000 population on all check-up and 1, 040 per 100, 000 population on the first check-up. The brain check-up-based evidence elucidates that the incidence of brain tumors is approximately 50 to 100 fold higher, in comparison with previous reports of Japanese prevalence. Multiphasic health tests are valuable for a differential diagnosis between primary and metastatic tumors. Brain check-up frequently discovers asymptomatic tumors. Thus, we should pay more attention to asymptomatic brain tumors in subjects with brain check-up.
