Epidemiology of Brain/Nervous System Tumors in Children

Posted by on Mar 2, 2014 in Archive |

Parviz Ghadirian, Ph.D.1,4, Kazem Fathie, M.D., Ph.D.2, Jean-Pierre Thouez, Ph.D.3 1Department of Nutrition, Faculty of Medicine, University of Montreal, and Centre de recherche, CHUM-Hotel-Dieu, Montreal, Quebec, Canada-Hospital Sainte-Justine, Research Center, Montreal, Quebec, Canada 2Chairman of The American Academy of Neurological and Orthopaedic Surgeons 3Department of Geography, Faculty of Arts and Sciences, University of Montreal, and Centre de recherche, CHUM-Hotel-Dieu, Montreal, Quebec, Canada Introduction In the United States cancer is relatively less frequent among children. It has been estimated that(1) only I in 540 children will develop cancer. The relative rate of cancer occurring before the age of 15 years and among children less than 5 years of age is around 40%.(2) Although this disease is uncommon among young individuals, the mortality due it is high, accounting for more than 11% of all causes of death among children.(3) In other words, childhood cancer is the second leading cause of death, after accidents. The age-adjusted rate for all cancers combined among white children aged less than 15 years in the United States is around 14.4 per 100,000 per year, while among blacks it is 11.8 (4). The most common malignancy in children is leukemia which represents almost one-third of all cancer sites.5 Malignant neoplasms of the brain and central nervous system(CNS) are the next most common cancer in children, at about one-fifth of all cancer sites. In other words, I out of 5 cancers in children involve brain tumors. In the United States, it appears that the major types of tumors in the CNS are astrocytomas (21%), medulloblastomas (19%), gliomas (18%), glioblastomas (14%), astroblastomas (13%) and, finally, ependymomas.(6) In general, because of early detection and progress with therapeutic methods, mortality due to malignant diseases as a whole during childhood has been decreasing. Although rnortality from all cancers in children fell in recent years, the incidence of childhood brain tumors increased in Japan.(7) In England, a significant rise (1.8% on average) in the annual incidence rate for all CNS cancers, particularly for neuroectodermal rumors (3. 1 % elevation) was observed in 1974-1995.(8) These increases are not explained by an increment in the proportion of histologically-verified tumors. Genetic Factors Susceptibility to certain types of childhood cancers may also follow an autosomal dominant pattern of inheritance. For example, it has been estimated that 40% of retinoblastomas are due in part to an autosomal dominant germ cell mutation.(9) Neurofibromatosis is another autosomal dominant syndrome associated with the occurrence of cancer in childhood.(10) Socio-economic Status It appears there is no significant association between socioeconomic status, ethnicity and CNS tumors.(8) Age In general, there is no apparent age-dependency of brain and CNS cancer sites, but a specific age pattern averages for some CNS malignancies. For example, neuroblastoma...

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The Relationship of Facet Asymmetry, Spina Bifida Occulta, and Transitional Vertebrae in the Lumbar Spine to Backache

Posted by on Mar 2, 2014 in Archive |

Charles F. Xeller, M.D., Mark Sanders, M.D., Mohammed Athari, M.D. and Ralph Gibson, M.D Introduction It was the purpose of this study to demonstrate any relationship of facet asymmetry, spina bifida occulta and transitional vertebrae to the possible causation of low back pain. Now, these specific vertebral anatomical anomalies are frequently identified on plain x-ray films. In the past, there have been several studies that have analyzed the possible relationship of these anatomical variations to backache, and the results have provided a wide range of differing conclusions. It was speculated that perhaps the difference in conclusions could possibly have resulted because different physicians diagnosed these anatomical variations with different rates of accuracy. In this study, 1,000 lumbar spine AP view x-rays were interpreted by 3 separate physicians and their conclusions in diagnosing the conditions of facet asymmetry, spina bifida occulta and transitional vertebrae were recorded. The 1000 patient x-rays were selected from 1000 consecutive emergency room visits. Five hundred fifty-three (553) patients were seen for diagnoses of mechanical low back pain. Four hundred forty-seven (447) were seen for diagnoses other than mechanical low back pain, but had x-rays of the LS spine. All physicians read the x-rays in isolation from the other two doctors. The physicians were also “blinded” as to whether the patient had back pain or not. Materials and Methods One thousand consecutive patients were recorded who presented to the emergency room and had an AP x-ray demonstrating the lumbar spine. The records and subsequent files were reviewed to establish whether the patient had a presentation of significant low back pain, or a different medical problem identified (such as a urinary tract infection). For this study, significant back pain was defined as pain that prevented the performance of manual labor or resulted in a prescription for analgesic medications. The x-rays were interpreted separately by 3 physicians for the presence of facet asymmetry, spina bifida occulta and transitional vertebrae. The doctors were not aware of the diagnosis for each particular case. All results were tabulated and then a statistical analysis was performed. Of the initial 11000 cases, 914 were included in this study. There was a drop out of 86 cases due to loss of records/x-rays, patient migration, or the lack of a diagnosis. Results and Statistical Analysis Of the 914 patients studied, 514 had a spina problem that manifested as backache, and 400 had another condition, the majority of which were identified as either prostate or kidney problems. The results of x-rays interpreted for facet asymmetry, spina bifida occulta and transitional vertebrae are presented in tables 1, 2, and 3, respectively. Table 1. Identification of Facet Asymmetry   Dr. A Dr. B Dr. C      ...

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Epidemiology of Bone Cancer: An Overview

Posted by on Mar 2, 2014 in Archive |

Parviz Ghadirian, Ph.D., Kazem Fathie, M.D., Ph.D., Jean-Francois Emard, Ph.D. Epidemiology Research Unit Centre Hospitalier de I’Universite de Montreal- Hotel-Dieu, and Department of Nutrition, Faculty of Medicine, University of Montreal American Academy of Neurological and Orthopaedic Surgeons Introduction Characteristics of bone cancer occurrence: Bone cancer is not a common cancer compared to many other types of cancer. The principal malignant tumors of bone are: a) osteosarcomas that occur mostly in the leg bones of children and young adults; this form is more frequent among girls under 15 and boys over 15; its incidence is higher among nonwhites than whites(1); b) chondro-sarcomas that usually afflict people over 40 years of age; this is a slow-growing tumor that often starts in the pelvic bones; and c) Ewing’s sarcoma, a cancer that impacts mainly children and teenagers; this form infiltrates large bones such as those of the thigh, upper arm, shin or pelvis; two times as many males are affected as females; a fast-growing tumor, its incidence is almost 9-fold higher among whites than blacks. According to the U.S. Surveillance, Epidemiology and End Results Program(2), osteosarcomas contribute 36% of all types of bone cancer, followed by chondrosarcomas and Ewing’s sarcomas with around 30% and 16% respectively. The incidence of osteosarcoma appears to be more frequent in two periods of life, during adolescence and old age. Regarding the geographical distribution of incidence (Table 1, Figures 1 and 2) and according to the Unit of Descriptive Epidemiology of the International Agency for Research on Cancer (IARC), only a few countries in Africa have reliable statistics on bone cancer. Among them, Mali has the highest standardized rate among males (1.4 per 100,000), while Algeria exhibits the highest rate among females (1.2 per 100,000), with a male/female ratio ranging from 0.75 to 1.55(3). In the Americas, Chinese males in Hawaii have the highest incidence rate of bone cancer (6.4 per 100,000). Actually, this is the highest rate in the world. Among females, Paraguay has the highest incidence rate in the region (1.6 per 100,000). The highest male-female ration (9.0) in the world is found among Japanese Americans in Los Angeles, California. In the United States, Filipino males and Japanese females have the lowest incidence rates for bone cancer. Canada has a moderate frequency rate of bone cancer within the America. In Canada, Quebec seems to have the highest, and New Brunswick, the lower rate of bone cancer patients. In Europe, Poland (Silesia) has the highest incidence rate of this disease in both males and females, with 2.4 and 1.5 per 10,000 respectively, while Italy shows the lowest rates for males and females. Both France and Sweden have the highest male/female ratio (3.5). In Australia, the incidence...

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