Chapter 7 Part 2 Flashcards
Key factors that contribute to likelihood of metastasis
lack of differentiation, aggressive local invasion, rapid growth, large size
expansion of benign tumor vs. localized invasion of malignant tumors
benign tumor will grow in size without initiating growth in other tissues; malignant tumors can penetrate blood vessels, lymphatics, body cavities and have the potential to metastasize in other tissues
Major pathways of dissemination via which a malignancy can metastasize
direct seeding (lack of barrier), lymphatic spread, hematogenous spread
Lymphatic spread
most common pathway for initial dissemination of carcinomas, spreads via lymphatic vessels to nodes
Sentinel node
first node in regional lymphatic basin that receives lymph flow from the primary tumor, must be biopsied to check for metastatic growth
Hematogenous spread of CA
typical of sarcomas, often venous spread to capillary beds, especially liver and lungs
CAs most commonly spread via hematogenous spread
carcinomas of thyroid and prostate, hepatocellular carcinomas and renal cell carcinomas
definition of incidence
number of new cases that develop over a period of time
definition of prevalence
number of cases present in a specific population at a given time
definition of mortality
measure of death frequency
Incidence of CA cases in 2008
12.7 million, 7.6 million deaths
Incidence and mortality of CA by 2030
21.4 million cases, 13.2 million deaths
Cancer incidence for men
Prostate (28%), lung (14%), colon and rectum (8%)
Cancer mortality for men
Lung (28%), prostate (10%), colon and rectum (8%)
Cancer incidence for women
Breast (29%), lung (13%), colon and rectum (8%)
Cancer mortality for women
Lung (26%), breast(15%), colon and rectum (9%)
Distribution of prostate and breast CA
most prevalent in developed nations (North America, south America, Australia, Europe)
Reasons for differing CA incidences
infectious agents, smoking, alcohol consumption, diet, obesity, reproductive history and age, environmental carcinogens
Influence of age in CA development
more common in later years of life due to accumulation of somatic mutations associated with emergence of neoplasms and decline in immune competence
