chapter 23 book notes Flashcards
cancers:
-diseases characterized by the uncontrolled growth of a group of abnormal cells
-destroy adjacent tissues and spread to other areas of the body via the lymph or blood.
The growth of what kind of tissue causes cancer?
-malignant (cancerous cell or tumor)
Cancer is the ?? most common cause of death in the U.S.
-2nd
The various types of cancer have different characteristics such as..
-occur in different locations in the body, take different courses, and require different treatments.
In the United States, the most common cancers are:
-breast cancer (in women),
-prostate cancer (in men),
-lung cancer
-colorectal cancers
carcinogenesis:
-the process of cancer development.
-proceeds slowly and for several decades
A cancer usually arises from ?? mutations that alter gene expression
in a single cell
-genetic
These alterations may promote
-cellular growth,
-interfere with growth restraint, or
-prevent cellular death
tumor:
-an abnormal tissue mass that has no physiological function;
-also called a neoplasm.
-Tumors may be malignant (cancerous) or benign (noncancerous)
metastasize:
-to spread from one part of the body to another; refers to cancer cells.
In leukemia (cancer affecting the white blood cells), the abnormal cells do not form a ?? ; they accumulate in the ?? and other tissues
-tumor
-blood
Some metabolic processes may initiate carcinogenesis, as when ?? (immune cells) produce ?? that cause DNA damage, or when chronic ?? increases the rate of cell division and the risk of a damaging mutation
-phagocytes
-oxidants
-inflammation
More often, cancers are caused by interactions between a person’s ??
and the ?? .
-genes
-environment
Various food components may alter processes of ??/, ?? , or ?? in ways that affect cancer development
-DNA repair, gene expression, or cell differentiation
obesity is a risk factor for a number of different cancers, including some relatively common cancers such as ?? cancer and ??? cancer
-colon
-postmenopausal breast
Obesity increases cancer risk, in part, by altering the levels of hormones that influence cell growth, such as /??, the ??? , and several kinds of ??? .
-insulin
-sex hormones
-growth factors
What hormone is involved in postmenopausal breast cancer in women? Why?
-estrogen
-obese women have higher estrogen levels than lean women do because adipose tissue is the
primary source of estrogen after menopause
The increase in circulating estrogen may create an environment that encourages ??? in breast tissue
-carcinogenesis
About 5 percent of cancers worldwide can be attributed to ?? consumption,
-alcohol
Although the ways in which alcohol affects cancer development are
not fully understood, some evidence suggests that ?? —the principal metabolite of alcohol—upsets DNA synthesis and repair, promoting carcinogenesis
-acetaldehyde
Food ?? methods can influence the production of carcinogens,,, like…
-preparation
-cooking meat, poultry, and fish at high temperatures (broiling & frying) or
-foods adhere to smoke present during grilling
However, the cancer risk from eating such foods is
?/ because the biological effects of these carcinogens are modulated by
other dietary components, including compounds in ??? and other ??
foods.
-unclear
-vegetables
-plant
Consuming fruits and vegetables may reduce the risks of some ??
-cancers
Possiblebenefit has been attributed, in part, to nutrients and phytochemicals that have
?? activity, as these substances may prevent or reduce the oxidative
reactions in cells that cause DNA damage
-antioxidant
The B vitamin folate (provided by certain fruits and
vegetables) functions in ??? and ?? ;
-DNA synthesis
-repair
thus, inadequate folate intakes may allow DNA ?? to accumulate.
-damage
Fruits and vegetables also contribute dietary fiber, which may help to protect against ?? and ?? cancers by diluting potential carcinogens in fecal matter and accelerating their
removal from the GI tract
-colon
-rectal
Components of ?? vegetables may
inhibit several types of cancer, including….
-nonstarchy
-head and neck cancers,
-lung cancer, and
-breast cancer
The complications that develop are often due to the
tumor’s ?? on surrounding tissues.
-impingement
?? is a major contributor to the weight loss often associated with cancer
-Anorexia
The ?? changes that arise in cancer contribute to weight
loss and nutrient depletion.
-metabolic
Cytokines:
-signaling proteins
-released by both tumor and immune cells to induce an inflammatory and catabolic state
Patients with cancer exhibit an increase in… and a decrease in…
-protein turnover rate
-muscle protein synthesis
Muscle contributes amino acids for ??? further depleting the body’s supply of protein.
gluconeogenesis (glucose production),
?? breakdown increases, elevating serum lipids
many patients with cancer develop…
Triglyceride
-insulin resistance
cancer cachexia:
-a wasting syndrome associated with cancer that is characterized by anorexia, muscle wasting, weight loss, and fatigue.
Cancer cachexia develops in about ?? percent of patients with cancer and is responsible for as many as ?? percent of cancer deaths
-50%
-30%
Cachexia may be indicated by an involuntary weight
loss of more than ?? percent of body weight over the preceding 6 months
-5
Unlike in starvation, nutrition intervention alone is ?? to reverse cachexia.
-unable
The primary medical treatments for cancer are:
-surgery,
-chemotherapy,
-radiation therapy,
or any combination of the three
The primary medical treatments for cancer aim to help…
-remove cancer cells
-prevent further tumor growth
-alleviate symptoms
Surgery is performed to…
-remove tumors,
-determine the extent of cancer,
-protect nearby tissues
surgery must be followed by other cancer ?? to prevent the growth of new tumors
-treatments
chemotherapy:
- the use of drugs to destroy cancer cells;
-“antineoplastic agents.”
-used to inhibit tumor growth, shrink tumors before surgery, and prevent or suppress metastasis
methotrexate:
-an anticancer drug that prevents cell division.
-Methotrexate closely resembles the B vitamin folate, which is needed
for DNA synthesis;
-the drug works by blocking activity of the enzyme that converts folate to its active
form
some cancer drugs have toxic effects on normal cells as well and are especially damaging to rapidly dividing cells, such as those cells in the… of the human body (3)
-GI tract, skin, and bone marrow.
The bone marrow damage can impair the production of ?? (causing anemia) and ?? (causing neutropenia)
-red blood cells
-white blood cells