Cancer Flashcards
What is the second leading cause of death?
Cancer (> 1 million diagnosed ea. year, >500,000 deaths per year)
What is a tumor and what is it also referred as?
- an abnormal growth of cells that serves no purpose or swelling that is caused by inflammation
- Neoplasm (new growth)
What are the characteristics of benign (non-cancerous) tumors?
- grow slowly
- cells have a well-defined capsule
- Non-invasive(doesn’t spread or invade other tissue)
- well differentiated cells
- slow mitosis
- localized(don’t metastasize)
What are the characteristics of malignant(cancerous) tumors?
- grow rapidly
- cells not encapsulated
- invasive
- poorly differentiated cells
- rapid mitosis
- Spreads rapidly(metastasis)
How are benign tumors classified?
they are named from the tissues that they are originated from
-Benign tumors can progress into cancer-
How are malignant or cancerous tumors classified?
- Anaplasia: loss of differentiation
- Pleomorphic: cells are variable in sizes and shape
Where do most cancers originate from?
In tissues with cells that replicate faster (ex: skin, respiratory tract, reproductive tract, bone marrow, GI tract, bone; from areas where cells naturally grow and divide rapidly
What is the difference between carcinomas and adenocarcinomas?
- Carcinomas: malignant epithelial tumors
- Adenocarcinomas: malignant tumors from ductal or glandular tissue
What is Carcinoma in situ (CIS)?
- Pre-invasive epithelial tumors
- A tumor that does not invade surrounding tissue
- Pre-cancerous(non-malignant)
Cancer is predominantly a disease of aging.
True/False
True
An individual acquires multiple mutations or genetic ‘hits’ over time, causing cancer to develop.
True/False
True
What are mutations in the environment that are cancer causing(or alter genetic makeup?
- Smoking
- UV Radiation(sunlight; damages epithelial cells over time with exposure)
Clonal Proliferation or Expansion?
- Is a result of mutations, allows cells to acquire characteristics of a cancer cell and have a selective advantage over its neighboring cells
- increased growth rate or decreased apoptosis of cells
What are transformed cells?
-transformed cells are cancer cells that can be created from normal cells in a lab setting
Characteristics of transformed cells
- decreased need for growth factors to multiply
- lack contact inhibition(cells jus pile up on each other)
- anchorage-independent(continue to divide in a soft-gel growing environment)
- immortal
Proto-oncogenes vs. Oncogenes vs. Tumor-Supressor Genes
- Proto-oncogenes: genes that regulate normal cell growth and proliferation; it is an oncogene in it’s normal, non-mutant state
- Oncogenes: over-expressed/mutated proto-oncogene
- Tumor-Supressor Genes(Anti-oncogenes): genes that encode proteins that inhibit proliferation of cancer genes; they are growth inhibiting genes(act like a brake pedal)
Gene Silencing
Turning off genes w/o mutations
-whole regions of a chromosome are shut off while the same regions in other cells remain active
what is chromosome instability?
- chromosomes are unstable, such that either whole chromosomes or parts of chromosomes are duplicated or deleted.
- an increase in malignant cells
- Results in chromosome loss, loss of heterozygosity, and chromosome amplification
Mutagens
any agent that causes a mutation
How can a mutation be passed onto future generations?
If the mutation occurs in germline cells or in other words gametes. This does not happen if it occurs in somatic cells.
Metastasis
- spread of cancer from a primary site of origin to a distant site
- it is highly inefficient; meaning it is not efficient or controlled
- usually occurs in later stages of cancer
True/False
Signs and Symptoms of a tumor vary according to its origin and size
True Manifestations of tumor include: -physical pressure -obstructions -loss of normal function -compression of nerves
What is a biopsy?
Consists of obtaining tumor tissue to confirm a diagnosis and to see whether the tumor is benign or malignant
What are the steps involved in determining the stage of a tumor? (3 total)
- Size
- the degree to which it has locally invaded
- the degree to which it has spread(metastasized)
What are the different stages?
Stage I: No metastasis
Stage II: Local Invasion
Stage III: Spread to regional structures(lymph nodes)
Stage IV: Distant metastasis
What is the World Health Organization’s TNM system for staging cancer?
T–> tumor spread(primary tumor)
N–> node involvement(regional lymph nodes)
M–>presence of distant metastasis
When lymph nodes are involved in cancer that is not a good thing along with the increasing size of tumor and degree of metastasis staging may also alter the choice of therapy
What are substances produced by benign or malignant cells that are present either in or on tumor cells or found in blood, cerebrospinal fluid, or urine. And what do they include?
Tumor (Cell) Markers or Biological Markers
Includes: Hormones, Enzymes, Genes, antigens, and Antibodies
What are tumor markers used for? and what problem do thay pose?
- Screen and identify individuals at high risk for cancer
- Diagnose specific types of tumors
- Observe clinical course of cancer
-Problem: false positives and negatives
Pain, Fatigue, Anemia, Leukopenia,Thrombocytopenia, Infection, Gastrointestinal Problems, Hair(alopecia) and Skin Problems are all a result of what?
These are all clinical manifestations of cancer.
Pain and Cancer
How does the pain occur?
- Little or no pain is associated with early stages of malignancy
- Most feared complication of advanced cancer
- Influenced by fear, anxiety, sleep loss, fatigue, and overall physical deterioration
Mechanisms of pain: Direct pressure, Obstruction, Invasion of sensitive structures, Stretching of visceral surfaces, Tissue destruction, Inflammation
Fatigue and Cancer
-Subjective clinical manifestation
*Tiredness, weakness, lack of energy, exhaustion,
lethargy, inability to concentrate, depression,
sleepiness, boredom, and lack of motivation
-Causes
*Sleep disturbances, treatment, psychosocial
factors, nutritional status (syndrome of cachexia)
Cachexia
- Severe form of malnutrition
- Present in 80% of cancer patients at death
- Includes anorexia, early satiety, weight loss, anemia, asthenia (lack of energy), taste alterations, and altered protein, lipid, and carbohydrate metabolism
Anemia and Cancer
What is the anemia in cancer patients caused by?
Anemia is the decrease of hemoglobin in the blood.
Caused by: Chronic bleeding resulting in iron deficiency, Severe malnutrition, Medical therapies (chemotherapy), Malignancy in blood-forming organs
Leukopenia/Thrombocytopenia as a Clinical Manifestation of Cancer
Cause and Risk
-Leukopenia: decrease of white blood cells
-Thrombocytopenia: decrease in the number of platelets
Cause:
-Direct tumor invasion to the bone marrow causes leukopenia (decreased total WBC) and thrombocytopenia (decreased total platelets)
-Chemotherapy drugs are toxic to the bone marrow
Risk:
Infection risk increases when the absolute neutrophil and lymphocyte counts fall
Gastrointestinal Manifestations with Cancer
-Oral ulcers caused by decreased cell turnover from chemotherapy and radiation, Malabsorption, Diarrhea, Therapy-induced nausea
Hair and Skin Manifestations with Cancer
- Alopecia from chemotherapy: usually temporary
- Skin breakdown and dryness
Effects of Chemo
Chemotherapy is very toxic: affects the gut, bone marrow, causes sores in the mouth(resulting in the inability to eat), burns, alopecia(side effect; hair will grow back)
