Porth's Essentials of Pathophysiology, 4e

ancer is a major health problem in the United States and many other parts of the world. It is estimated that 1.66 million Americans were newly diagnosed with cancer in 2013 and 580,350 died of the disease. 1 Cancer affects all age groups, and is the second leading cause of death among children ages 1 to 14 years. 1 As age- adjusted cancer mortality rates increase and heart dis- ease mortality decreases, it is predicted that cancer will soon become the leading cause of death. The good news, however, is that the survival rates have improved to the extent that almost 64% of people who develop cancer each year will be alive 5 years later. Cancer is not a single disease. It can originate in almost any organ, with skin cancers being the most com- mon site in persons in the United States. Excluding skin cancers, the prostate is the most common site in men and the breast is the most common site in women (Fig. 7-1). The ability of cancer to be cured varies considerably and depends on the type of cancer and the extent of the disease at the time of diagnosis. Cancers such as acute lympho- blastic leukemia, Hodgkin disease, testicular cancer, and osteosarcoma, which only a few decades ago had poor prognoses, are cured in many cases today. However, lung cancer, which is the leading cause of death in men and women in the United States, 1 remains resistant to therapy. This chapter is divided into five sections: characteris- tics of benign and malignant neoplasms, etiology of can- cer, clinical manifestations, diagnosis and treatment, and childhood cancers and late effects on cancer survivors. Hematologic malignancies (lymphomas and leukemias) are presented in Chapter 11. C Neoplasia 7 C h a p t e r Cancer is a disorder of altered cell differentiation and growth. The resulting process is called neoplasia, and the new growth is called a neoplasm . Unlike the pro- cesses of hypertrophy and hyperplasia that are discussed in Chapter 2, the cell changes that occur with neoplasia tend to be relatively uncoordinated and autonomous, lacking normal regulatory controls over cell growth and division. Normal renewal and repair involves two components: cell proliferation and differentiation (see Chapter 4). Proliferation, or the process of cell division, is an inherent Characteristics of Benign and Malignant Neoplasms

Characteristics of Benign and Malignant Neoplasms Terminology Biology of Benign and Malignant Tumors Benign Neoplasms Malignant Neoplasms Tumor Cell Characteristics Tumor Growth Invasion Metastatic Spread Etiology of Cancer Genetic and Molecular Basis of Cancer Cancer-Associated Genes Epigenetic Mechanisms Molecular and Cellular Pathways Tumor Cell Transformation Host and Environmental Factors Heredity Hormones Obesity Immunologic Mechanisms Chemical Carcinogens Radiation Viral and Microbial Agents Clinical Manifestations Local and Regional Manifestations Systemic Manifestations Anemia Anorexia and Cachexia Fatigue and Sleep Disorders Paraneoplastic Syndromes Screening, Diagnosis, and Treatment Screening Diagnostic Methods Tumor Markers Cytologic, Histologic, and Gene-Profiling Methods Staging and Grading of Tumors Cancer Treatment Surgery Radiation Therapy Chemotherapy Hormone and Antihormone Therapy Biotherapy Targeted Therapy Childhood Cancers and Late Effects on Cancer Survivors Incidence and Types of Childhood Cancers Biology of Childhood Cancers Diagnosis and Treatment Survivors of Childhood Cancers

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