CHAPTER INTRODUCTION 14

Often thought of as one disease, cancer is the name for a group of over 100 different types of diseases where abnormal cells grow out of control and can spread throughout the body. According to the American Cancer Society (ACS), men have a 1 in 2 lifetime risk of being diagnosed with cancer and women have a 1 in 3 lifetime risk (1). The leading sites of cancer for men are prostate, lung, colorectal, and urinary bladder. For women the most prevalent sites of disease are breast, lung, colorectal, and uterine corpus. In 2014, the ACS estimated there were 13.7 million cancer survivors in the United States. A cancer survivor is defined by the ACS as anyone living with a cancer diagnosis who is undergoing cancer treatment, cancer free, or living with evidence of disease. Advances in cancer prevention efforts, early detection, and the development of new anticancer therapies have led to the improvement in overall survival of 67% for all cancers, up from 47% in the 1970s. Fewer Americans are dying from cancer; however, cancer is still responsi- ble for almost 1 in 4 deaths in the United States each year (1).

Cancer is a disease of aging and growing older, with 78% of cancers being diagnosed in persons 55 years or older (1). Sixty percent of all cancer survivors in the United States are 65 years or older and the US Census Bureau projects that this group will grow by over 60% between 2000 and 2020 and will increase by an estimated 120% by the year 2050 (2). Men typically have higher rates of cancer than women, and African Americans experience higher rates than other races. It is estimated that almost 75% of older adults have at least one chronic and/or comorbid disease such as cancer, heart disease, lung disease, diabetes, arthritis, or osteo- porosis, and nearly 50% of this population has at least two chronic diseases and/or comorbidities (3). According to leading cancer research organizations, approximately a quarter to a third of all cancers could be

Consequences of Cancer

prevented through improvements in nutrition and physi- cal activity and by achieving and maintaining a healthy body weight (1,4). The American Institute for Cancer Research/World Cancer Research Fund (AICR/WCRF) has published evidence-based recommendations for decreasing cancer risk through healthy lifestyle changes. See Box 14.1 for a summary of cancer prevention rec- ommendations from the AICR/WCRF.

IMPACT OF MALNUTRITION IN CANCER

It is estimated that approximately 20% of older adults are malnourished, and many more are at risk for mal- nutrition (5). Malnutrition in the oncology setting is defined as changes in body composition and undernu- trition as a result of cancer and its treatment. The Academy’s Oncology Nutrition Evidence-Based Nutrition Practice Guideline (ON EBNPG) Workgroup found that the consequences of malnutrition for indi- viduals with cancer include reduced response and tol- erance to treatment, impaired wound healing and immune function, reduced muscle strength, and increased fatigue. Significant weight loss and poor nutritional status have been reported in more than 50% of these individuals at the time of cancer diagnosis, and the incidence of malnutrition and weight loss varied, depending upon cancer site (7,8). Proactive nutrition screening, assessment, and interventions for malnutrition can positively impact quality of life, body composition and function, treatment tolerance, and clinical outcomes (6).

NUTRITIONAL CONSEQUENCES OF

CANCER AND ITS TREATMENT Symptoms of cancer and side effects of cancer treat- ment can contribute to an individual’s ability to ingest, digest, or absorb nutrients. Eating-related challenges that impact nutritional status can occur due to the