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We used New Zealand data on occurrence of different types of brain cancer to investigate: (i) a possible secular increase which has been seen worldwide and has generated considerable debate; (ii) possibly higher rates among Maori; and (iii) possibly higher risks related to social class and occupation. Data from the NZ Cancer Registry on the 5,684 brain cancers diagnosed among NZ residents from 1948-88 were used to study the pattern of occurrence by gender, age, race, calendar year, social class, occupation, and histology. Age-standardized brain-cancer incidence rates per 100,000 more than doubled over the 41-year period (from 2.9 to 6.9 in males and from 2.1 to 5.1 in females). A strong trend of increasing incidence with increasing social class is seen in males (Ptrend = 0.01). Among Maori, the proportion of all brain cancer that is medulloblastoma is four times that among non-Maori, and the proportion of all brain cancers that lack histologic confirmation is about 40 percent higher. Elevated risks are seen among: dairy farmers (odds ratio [OR] = 3.4, 95 percent confidence interval [CI] = 1.9-6.0); sheep handlers (OR = 2.7, CI = 1.4-5.3); livestock workers (OR = 3.8, CI = 1.7-8.4); and farm managers (OR = 3.2, CI = 1.4-7.2); as well as among electrical engineers (OR = 8.2, CI = 20-34.7); electricians (OR = 4.6, CI = 1.7-12.2); and other electrical workers. Brain cancer rates in NZ have increased steadily since 1948, but this increase has leveled off in the most recent five-year period. Although brain cancer rates are likely to be underestimated among the Maori, an excess of medulloblastoma is evident in this group.

We have re-examined histopathological specimens of brain tumors extirpated at China Medical University from May, 1990 to June, 1992. During the last 2 years, about 400 cases of brain tumors were operated and 349 cases were histopathologically diagnosed and classified by one of the authors (T. I). The most common tumor was meningioma, 97 cases, followed by gliomas, 87 case and neurinoma, 71 cases. The sex and age distributions of these three tumor types were compared to those of Kyushu University Hospital, Japan. The most striking difference was age of meningioma and neurinoma patients, and Chinese patients were 10 years younger than Japanese patients. The incidence of 30th age group of meningioma was 25% in China and 10% in Japan. Thirty percent of neurinoma patients were operated at 30th and 40th age in China and Japan, respectively. The sex and ages of astrocytoma patients were almost the same frequencies in China and Japan. Among 22 cases of congenital tumors, 11 cases of epidermoid tumor in cerebello-pontine cistern was included. Cerebral tuberculoma, although rarely encountered in Japan, was 2 cases in China.

Although Western medicine helps people understand disease and death in scientific terms, patients often explain their illnesses very differently. The explanations held by patients and their families from 'foreign' cultures can be bewildering to the clinician. In treating immigrant patients, particularly those with terminal illness, it is essential to understand their own explanations. Clinically applied medical anthropology considers how the patient's culture shapes his understanding of disease. In an effort to apply an anthropological approach to the pediatric setting, a cultural consultation service was developed at the Royal Children's Hospital in Melbourne. This service involved a team which included a psychiatrist (with anthropological training), an anthropologist, and several Southeast Asian community members. One patient for whom the service consulted was an adolescent Cambodian boy with glioblastoma multiforme, stage IV. This case is analyzed in the light of the culturally determined problems in management and the culturally embedded meaning of the illness. The patient's belief in ancestral and house spirits as well as his belief in the Theravada Buddhist doctrine of karma is examined. The case demonstrates how belief in such religious phenomena does not necessarily preclude compliance with Western health care.

This report presents data on the distribution of 8,612 cases of primary tumors of the brain, cranial nerves and cranial meninges (both benign and malignant) diagnosed among residents of Los Angeles County from 1972 to 1985. Incidence rates of gliomas, meningiomas, nerve sheath tumors and all histologic types combined are presented for specific age, sex and ethnic groups. At all ages, the highest incidence is seen for gliomas among men. Meningioma rates are higher among women than men in every ethnic group. In both sexes, glioma rates are highest among whites, and meningioma rates are highest among blacks. Asians have the lowest rates of both types of tumors. Proportional incidence ratios are elevated among those born in Eastern Europe, Southern Europe and the Middle East and among Jewish residents of Los Angeles County. A clear trend of increasing glioma incidence with increasing social class is seen among males. An analysis among white men aged 25-64 by occupation and industry at the time of diagnosis supports several previously published findings. A glioma excess is evident among workers in the aircraft industry. Workers in the petroleum industry and the rubber and plastics industry have an excess of meningiomas. Occupational groups at excess risk include dentists who have an increased risk of all types of brain tumors and electricians whose excess risk is limited to gliomas.

Racial patterns of childhood brain cancer by histologic type were studied using data from the Third National Cancer Survey and the Surveillance, Epidemiology, and End Results Program. Incidence rates for whites of all types combined and of astrocytic glioma and medulloblastoma were slightly higher than those for blacks. Proportionately more black than white cases of astrocytic glioma were diagnosed between the ages of 5-9 years; this difference corresponded to twofold-higher rates at ages of 0-4 and 10-14 years and similar rates at ages of 5-9 years among whites compared to rates among nonwhites. A real difference in age-incidence curves rather than diagnostic delay among blacks appeared to explain the differences. For medulloblastoma, the male-female rate ratio differed between whites (1.7) and blacks (1.0). Time trend analyses revealed statistically significant increases in medulloblastoma and glioma not otherwise specified (NOS) for incidences among blacks. The rate of microscopic confirmation was significantly higher among whites than among blacks, a difference apparently not explained by differences in the accessibility of tumors for biopsy. For avoidance of biased comparisons, differences in rates of microscopic confirmation and time trends for glioma NOS should be considered in studies of racial patterns of childhood brain cancer incidence by histologic type.

All Canadian deaths due to malignant brain tumour for the years 1970-73 were identified and analysed for country of birth. The years 1970-73 were chosen since in later years country of birth was no longer available for each death. The brain tumour population consisted of 1551 male and 1058 female deaths and matched controls were chosen from deaths due to other causes. Americans who died of brain tumour in Canada had a standardized mortality ratio (SMR) of 1.0 compared to their fellow Americans in the USA. Italian, German, Dutch and British immigrants had SMR between 1.5 and 2.6 compared to rates in their home countries and between 1.24 and 2.09 when compared to Canadian rates. A series of graphs shows the increased risk for male immigrants quite dramatically, and indicates that for females the increases were less pronounced. Further analysis showed that the excess risk is confined to those who were born in Western Europe while their Canadian-born children experienced the same rates as all Canadians. Based on the limited information available, occupation could not be shown to play a role in establishing risk. An attempt was made to pinpoint the years of immigration which showed the greatest risk. It is concluded that the determination of risk of brain tumour has a strong environmental component. The possibilities for identification of this component are discussed.

One hundred and sixty-eight cases of tumours of the central nervous system (CNS) from Chinese patients in Hong Kong were reviewed histologically as well as by the immunoperoxidase techniques in equivocal cases. Detailed comparisons were made between this series and previously published series on CNS tumours in Chinese, in other Asians and in Caucasians. The percentage of gliomas was low, and the average age of patients with high grade astrocytomas was low. Meningiomas were relatively common tumours and microcystic meningiomas were a common histological subtype. The percentages of vascular malformations and haemangioblastomas were also higher than those recorded in the West. The difference in incidence in gliomas and vascular malformations between this series and previous reports from mainland China was attributed to a possible difference between southern and northern Chinese.