General Considerations of Neoplastic Diseases



General Considerations of Neoplastic Diseases


C. Philip Steuber



By any measure, cancer in children is a rare disease, accounting for approximately 8,600 cases annually among children younger than 14 years in the United States and 3,700 cases annually in the 15- to 19-year-old age group. The annual incidence is approximately 17 cases per 100,000 individuals at risk. Nevertheless, cancer remains the leading cause of death from disease in children between 1 and 18 years of age. In contrast, more than 1.2 million new cases of cancer are diagnosed annually among adults. This disparity in numbers is not wholly attributable to the relative size of the populations of adults and children but reflects the significant role of chronic environmental exposures in adult cancer. Although more than 85% of adult malignant neoplasms are carcinomas, carcinomas are rare in children. The most common cancers in children are the acute leukemias (30%) and central nervous system tumors (18%). Environmental factors do play a role in pediatric carcinogenesis, but the associations are different for pediatric patients than for adults. Some pediatric neoplasms are associated with developmental defects, anomalies, or cytogenetic or molecular aberrations and can be anticipated on the basis of preexisting immunologic deficiency states, genetic and chromosomal disorders, and congenital anomalies (Box 299.1 and Tables 299.1, 299.2 and 299.3). When identified, such patients require careful observation and regular evaluation to enable early detection and optimal management. Environmental factors may play a role by triggering neoplastic transformation or activating preexisting defects. In general, however, the incidence of childhood cancers attributable to a defined inherited or congenital predisposition or environmental factor is low. A family history of a high incidence of cancer is an important consideration. Some of the syndromes described may not manifest fully until the individual is older and need not be considered in the very young infant or child.

Except for these uncommon circumstances and conditions, the detection of cancer in children requires the caregiver to be alert to the possibility. Early diagnosis of childhood cancer often is delayed because of the nonspecific nature of the initial signs and symptoms, the relative rarity of pediatric cancers, and a low index of suspicion. The seven warning signs of cancer in adults are of limited help in evaluating the pediatric patient. Warning signs in children can include fever, persistent headache, pain, a mass, purpura, pallor, and changes in gait, balance, personality, and the eyes (e.g., squint, retinal reflections), all of which may evolve insidiously. Some of these are common
nonspecific pediatric complaints with common explanations, but the alert primary physician can quickly sort out the unusual from the usual problems.

Jul 24, 2016 | Posted by in ORTHOPEDIC | Comments Off on General Considerations of Neoplastic Diseases
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