Neoplasia: Epidemiology

• Top 3 cancers for men: Prostate (30%), Lung and bronchus (14%), and Colon and rectum (11%)

• Top 3 cancers for women: Breast (31%), Lung and bronchus and colon and rectum (each 12%)

• Top 3 cancer deaths for men: Lung and Bronchus (31%), Prostate (11%), and Colon and rectum (10%)

• Top 3 cancer deaths for women: Lung and Bronchus (25%), Breast (15%), and Colon and rectum (11%)

Age: The frequency of cancer increases with age. Most cancer mortality occurs between the ages 55 and 75 years; the rate declines, along with the population base, after age 75. The rising incidence with age may be attributed to the accumulation of somatic mutations associated with the emergence of malignant neoplasms. The decline in immune competence that accompanies aging also is a factor.

Cancer causes slightly more than 10% of all deaths among children younger than 15 years. The major lethal cancers in children are leukemia, tumors of the CNS, lymphomas, soft tissue sarcomas, and bone sarcomas.

Occupation: Different occupations cause one to be exposed to various harmful agents. See question 5 and table 6-3 for a complete list.

Environment: Environmental factors are the predominant determinant of the most common sporadic cancers. There is no paucity of environmental carcinogens. They lurk in the environment, workplace, food, and personal practices. They can be anything from sunlight, diet, cigarette smoking, alcohol consumption, number of sex partners, etc. Some examples of environmental/geographic cancers: Death rates from breast cancer are about fourfold higher in America compared with Japan. The death rate for stomach carcinoma in men and women is about seven times higher in Japan than in the United States.

Heredity: Heredity forms of cancer can be divided into 3 categories which include the following: Inherited Cancer Syndromes (autosomal dominant), Familial cancers, and Autosomal Recessive Syndromes of Defective DNA Repair.

• Examples of Inherited Cancer Syndromes: Familial retinoblastoma, familial adenomatous polyposis, multiple endocrine neoplasia, neurofibromatosis types 1 and 2, von Hippel-Lindau syndrome

• Examples of Familial Cancers: Breast cancer, ovarian cancer, colon cancers

• Examples of Autosomal Recessive Syndromes of Defective DNA repair: Xeroderma pigmentosom, ataxia telangiectasia, bloom syndrome, and fanconi anemia.

Category: Pathology Notes