Mod 2 Cancer and genetics Flashcards
Abrasion
an injury caused by rubbing or scraping that results in the loss of the superficial layer of skin
Angiogenesis
the process of forming new blood vessels.
Occurs in the granulation phase of healing in wound repair.
Or in cancer when cancer cells stimulate blood vessel growth to feed a tumor by sending out growth signals
Approximation
Word used to describe when wound edges are touching (all wound margins are approximated)
All surfaces need to be touching to heal.
Applies to wounds healing by 1st or 3rd intention
Avulsion
a wound that results from tissue being torn away in large piece
REQUIRES HEALING BY SECONDARY INTENTION
Cellulitis
inflammation or infection of the cells in tissues characterized by SHARP
Debridement
the removal of devitalized or dead tissue and foreign material from the wound bed
A wound should be clear of dead or revitalized tissue to support healing and reduce the risk of infection
there are many ways to debride a wound
Dehiscence
The splitting open of a surgical wound (a wound that had been sutured closed)
Erythema
redness of the skin
caused by vasodilation related to inflammation, infection, or injury
Exudate
Fluid that comes from wounds. can be clear (serous) sanguineous (bloody) or purulent (pus)
Granulation Tissue
forms in the wound base which fills in wound with scar tissue.
The tissue is red or pink and has a lumpy appearance like small grapes.
The tissue is necessary to fill in wounds for healing.
Ischemia
A deficiency of blood supply to an area of tissue or an organ
Laceration
a wound that is produced by the tearing of cutting of the skin
Maceration
a softening, whitish look to the intact skin around wounds caused by excessive moisture. Often occurs when exudate is not well managed by dressings
also occurs when briefs are not changed often enough.
Necrotic Tissue
dead tissue that usually presents as black or brown and is hard or leathery in texture (eschar) Must be removed for the wound to heal. Very prone to infection
Purulent
Containing or forming pus. Usually yan opaque white, green, or yellow exudate
3 Types of Healing Intention
Primary intention
Secondary Intention
Tertiary Intention
Primary Intention
Wound margins are brought together by any means
(sutures, steri-strips, glue, band-aid, staples)
and heals with minimal scaring or infection
incisions, cuts, and puncture wounds, are likely to heal by primary intention
Secondary intention
missing tissues requires margins to contract, and then fills-in, resulting in a large scar. Cannot be sutured closed because too much tissue is missing. High infection potential
*Larger wounds with loss of tissue and contamination (such as experienced in a bicycle crash) are likely to heal by secondary intention. Also pressure ulcers
Tertiary Intention
Wound margins either separate after being closed (surgery incisions dehisces) or are intentionally left open (to allow infection to drain out of the wound) then brought together (and closed with stitches) after granulation tissue appears. This is a combination of primary and secondary closure
*This type of closure is preferred when wound in heavily contaminated to reduce the risk of wound infection. The wound is cleansed and is watched closely for several days. When the wound appears to be clean on its way to healing it is closed surgically (dog bites etc.)
Nutritional Status effect on wound healing
Blood flow/ O2 delivery effect on wound healing
Impaired Inflammatory/ immune response effect on wound healing
Infection effect on wound healing
Wound separation effect on wound healing
Foreign Bodies effect on wound healing
Benign Characteristics
Cell characteristics: Well differentiated
cellular cohesiveness: Stays together
growth mode: expands and pushes on surrounding tissue
growth pattern: encapsulated
growth rate: generally slow
metastatic potential: does not metastasize
tumor mobility: movable
Malignant Characteristics
cell characteristics: Poor differentiation
Cellular cohesiveness: Breaks apart, sluffs off easily
Growth mode: infiltrates into tissue
Growth pattern: infiltrates tissues
Growth rate: usually rapid
metastatic potential: eventually metastasizes
tumor mobility: fixed
Differentiation with cancers
Tumors lose differentiation features over time as they multiply and become more “malignant”
Poor cellular differentiation increases the growth rate. A tumor neoplasm that is well differentiated (retains most of the cellular characteristics of the tissue it is from)
*well differentiated = benign
*poorly differentiated = malignant
if it is malignant it loses the characteristics that made it a unique type of cell and it no longer functions as normal tissue
Contact inhibition with cancers
the cessation of growth after a cell comes in contact with another cell. blocking the synthesis of DNA, rna, and proteins.
When cell membranes come in contact with each other, they stop reproducing.
*cancer cells tend to grow rampantly despite coming into contact with other tissue
Cohesiveness with cancers
normal cell membranes help support each other by sticking together when they come in contact with each other. Malignant cells lack this cohesiveness
this is why malignant cells SPREAD EASILY. they do not have cellular support from the other cells. the least little bump or contact can cause the cancer cells to shed and spread
Anchorage independence with cancers
Normal cells must be “anchored” to a membrane or matrix of some kind to grow (except blood cells). Cancer cells can move freely (and therefore metastasize)
Faulty Cell to Cell communication with cancers
Chemical messengers bind to specific cell surface receptors, control cell growth, and modify cell behavior.
It may interfere with the formation of intercellular connections and responsiveness of membrane-derived signals.
*The cancer cell does not get the message to stop growing
Antigen Expression with cancers
Cancer cells express a number of cell surface molecules or antigens that are immunologically identified as foreign.
Tumor antigens may be used clinically as markers to indicate the presence or progressive growth of a cancer
Enzymes with cancers
Most cancers synthesize and secrete enzymes (proteases and glycosidase). breaks down proteins involved in insuring intracellular organization and cell to cell cohesion. may contribute to the breakdown of intercellular matrix
Sentinel node
the initial lymph node to which the primary tumor drains. Once the sentinel node is identified, it is examined to determine the presence or absence of cancer cells which indicates how far the cancer has spread
Benign tumors nomenclature
usually are named by adding the suffix -oma
Malignant tumors of epithelial origin nomenclature
usually named by adding the suffix -carcinoma
Carcinoma is the more common form affecting epithelial tissues, skin and mucous membranes lining body cavities
Malignant tumors of mesenchymal nomenclature
mesenchymal = connective tissue tumors (bone, muscle, and cartilage)
called sarcomas
sarcoma is the less common cancer but it spreads more rapidly and is highly malignant
Rapidly growing tumors
show little diffentiation and this lack of form is referred to as anaplasia (meaning without form)
*they are most responsive to radiation treatment
Oncogenesis
the genetic mechanism whereby normal cells are transformed into cancer cells
Oncogene
mutated gene that now has the potential to cause cancer
Oncogene types
Proto-oncogene
-cellular oncogenes
-viral oncogenes
Mutated anti-oncogene
Proto-oncogene
an otherwise normal gene with a “genetic weakness”
more susceptible to being converted into an oncogene due to mutations from either inherited predispositions or external causes
the mutations in proto-oncogene disable normal apoptosis of cells which then results in over production of cells which is what will lead to cancer
Proto-oncogene (Cellular oncogenes)
cancer characteristics that are coded on the host’s inherited genes. Most human cancers are due to new mutations of cellular oncogenes to the oncogene form (also called cellular proto-oncogene)
Proto-oncogene (viral oncogene)
Some viruses are known to cause cancer by transmitting their DNA or RNA into host cells which damages the cells’ genes
Mutated anti-oncogene
When anti-oncogenes (tumor supressing genes) are damaged by mutation this leads to under production of cancer preventing cells
Host factors
Heredity
hormone
faulty immunologic mechanisms
obesity
smoking
alcohol
Environmental factors
Chemicals
radiation (including sun)
pollution
food
molds
tanning beds
oncogenic viruses
mutation of oncogenes by viruses can be linked to cancer formation
-Human papilloma Virus
-human t-cell lymphotropic virus
Methods of metastasis
Direct extension
seeding
circulation
Direct extension
tumor cells spread to tissues adjacent to the primary tumor by sending out projections (tentacles) into the surrounding tissue or growing pseudopodia to “walk “ to the nearest cells
Seeding
Tumor cells slough off from the primary tumor and develop into more tumors
ex: during surgery to remove a tumor some tumor cells remain in the tissue after the main tumor is removed and provide the seed for more tumor cells to grow
Circulation
(through blood and/ or lymph) a secondary tumor develops in a site distant from the primary tumor
staging definition
describes the severity of a person’s cancer based on the size and/ or extent (reach) of the original (primary) tumor and whether or not cancer has spread in the body
staging is important for several reasons like:
-staging helps the doctor plan the appropriate treatment
-cancer stage can be used in estimating a person’s prognosis
-staging helps health care providers and researchers exchange information about patients
TNM staging system stands for
T- Tumor
N- Lymph Nodes
M- Metastasis
TNM staging purpose
-To see the size or reach of the tumor
-Whether it reached to lymph nodes
-whether there is the presence of metastasis or secondary tumors formed by the spread of cancer cells to the other parts of the body.
TNM staging systems numbers meaning
a number is added to each letter to indicate the size and or extent of the primary tumor and the degree of cancer spread
Primary Tumor abbreviation meanings
TX: primary tumor cannot be evaluated
T0: no evidence of primary tumor
Tis: Carcinoma in situ
T1, T2, T3, T4: Size and/ or extent of the primary tumor
Regional Lymph Nodes abbreviation meanings
NX: regional lymph nodes cannot be evaluated
N0: No regional lymph node involvement
N1,N2,N3: Degree of regional lymph node involvement (number and location of lymph nodes)
Distant Metastasis Abbreviation meanings
MX: Distant metastasis cannot be evaluated
M0: No distant metastasis
M1: Distant metastasis is present
Stage 1 Staging system def
Location of tumor: In situ
Definition: Abnormal cells are present only in the layer of cells in which they developed
Stage 2 Staging system def
Location of tumor: Localized
Definition: Cancer is limited to the organ in which it began - no evidence of spread
Stage 3 staging system def
Location of tumor: regional
Definition: Cancer has spread beyond the primary site to nearby lymph nodes or tissues and organs
Stage 4 staging system def
Location of tumor: Distant/ metastatic
Definition: Cancer has spread from the primary site to distant tissues or organs or to distant lymph nodes
Unk
Location of tumor: Unknown
Definition: There is not enough information to determine the stage
Tumor grade
NOT THE SAME AS THE STAGE OF CANCER
-tumor grade is the description of a tumor based on how abnormal the tumor cells and the tumor tissue look under a microscope
-it is an indicator of how quickly a tumor is likely to grow and spread
Tumor grading scale
GX
Grade 1
Grade 2
Grade 3
Grade 4
GX
Grade cannot be assessed (undetermined grade)
Grade 1
Well differentiated, least aggressive
Grade 2
Moderately differentiated
Grade 3
Poorly differentiated
Grade 4
Very poorly differentiated. More likely to progress quickly, highly malignant
Fatigue
The most frequently reported symptom
Causes of fatigue:
-sleep disturbance
-biochemical changes secondary to disease and treatment
-psychological factors
-activity
-nutritional status
-environmental and physical factors
Pain
Caused by:
-pressure/stretching
-obstruction
-invasive tissues by tumor
Manifests in later stages
Pain management is a major concern in cancer treatments
Blood dyscrasias
Blood component disorders
caused by: bone marrow damage from various cancer treatments
Examples of blood dyscrasias
Anemia
Leukopenia
thrombocytopenia
Anemia
Low red blood cell count
caused by:
bleeding
malnutrition
cancer treatments (especially radiation)
tumor may ulcerate or erode blood vessels (bleeding)
causes:
decreased delivery of oxygen to tissues and least to patient fatigue and s/s of low O2
Leukopenia
Low white blood cell count
caused by:
bone cancers
cancer treatments
Cancer patients are prone to infections
Thrombocytopenia
Low platelet count
caused by:
bone cancers
cancer treatments
causes:
thrombocytopenia (bleeding disorders) which turns into anemia
Infection
The most significant cause of mortality of cancer patients
Increased risk due to:
malnutrition
blood dyscrasias
bone marrow suppression (immunosuppression from radiation and chemo treatments)
Tissue breakdown occurs and the patients immune system is weakened
becoming less mobile causes secretions to build up in lungs (pneumonia)
Cachexia
Wasting Syndrome related to malnutrition due to INCREASED BMR (basal metabolic rate) caused by growing tumors
-results in loss of skeletal muscle mass that cannot be fully reversed by nutrition.
-Loss of skeletal muscle leads ultimately to loss of body function.
Multifactorial causes including:
fatigue, stress, anorexia, and rapidly growing tumor “stealing nutrition” from the body
Cachexia commonly caused by
Tumors: Increase the patient’s basal metabolic rate (more calories are needed to maintain muscle mass)
Chemo: Taste buds are destroyed, patients don’t wanna eat, also causes severe nausea and vomiting (CINV = “Chemotherapy-induced nausea and vomiting)
Immunosuppressed: Allows overgrowth of opportunistic pathogens such as oral yeast that causes mouth sores (mucositis or stomatitis) patients will not eat because it is too painful
Curative
Cancer will be eliminated from the individual. Treatment is intended to bring out a COMPLETE CURE of the cancer (doesn’t always work)
Control
if the cancer is treated but does not completely go away it can be controlled and managed as a chronic disease
Palliative
treatment given ONLY TO RELIEVE CANCER SYMPTOMS AND REDUCE THE SUFFERING caused by cancer
Adjuvant Therapy
Treatment that is given IN ADDITION to the primary treatment to make sure the cancer is eradicated
Chemotherapy TX
not selective in the cells it kills
-*chemo drugs kill ALL FAST GROWING cells whether they are cancerous or not
Other normal fast-growing cells are damaged
- *GI Tract cells and bone marrow
Adverse reactions of chemotherapy
GI Tract
Bone Marrow Suppression
Secondary malignancies
Alopecia
Adverse reactions of chemotherapy: GI tract
the lining of the GI tract consists of fast growing cells
-Severe nausea/ vomiting (CINV)
-Mucositis/ stomatitis
-diarrhea or constipation (bowel obstructions can cause death)
Adverse reactions of chemotherapy: Bone Marrow Suppression
Bone marrow: fast-growing blood cells
chemo can result in a reduction of ALL blood components- RBC, WBC, and platelets
Adverse reactions of chemotherapy: Secondary malignancies
can be caused by the caustic chemotherapy agents used to treat the primary tumor
Adverse reactions of chemotherapy: Alopecia
Hair loss because hair follicles are fast-growing cells.
Mucositis (stomatitis)
Chemotherapy-induced mucositis common complication of therapy
3-10 days after the initiation of chemotherapy and lasts 7-14 days
causes ulcers in the mouth
ulcers act as a site for local infection
contributes to: Pain, Malnutrition, Cachexia, and infection
Radiotherapy (radiation) TX
ionizing radiation may be used externally or internally (implants) most effective for rapidly growing, poorly differentiated tumor cells
-usually used with chemotherapy and or surgery as adjuvant therapy
-can be used to reduce the size of a tumor and provide comfort
adverse reactions of radiotherapy
Skin burns
GI tract
Bone marrow suppression
Alopecia
Surgery TX
May be curative, adjuvant, or palliative therapy
Surgery may be done to assist with TNM
Adverse outcomes are related to:
-the nature of the surgery
-how far advanced the cancer has progressed
-blood loss
-patients general condition prior to surgery etc.
Biotherapy (immunotherapy) TX
Medications stimulate the immune system to identify and destroy cancer cells without damaging surrounding normal cells.
BRMs are a class of drugs that are used to treat cancer by altering or augmenting naturally occurring processes within the body
BRM Medications:
Enhance: an immune response (as might be needed to stimulate “seek and destroy” actions against cancer cells
Suppress: suppresses the immune system as might be needed to treat autoimmune disorders where a person’s immune system is over active
Advantaged of immunotherapy
-High specificity for antigens - means less damage to healthy tissue (but there are still negative side effects)
-immune memory cells give long protection
Disadvantages of immunotherapy
-Negative side effects are similar to chemotherapy and radiotherapy
-Side effects include: Nausea and vomiting, diarrhea, loss of appetite, fever and chills, muscle aches, weakness, skin rash, and increased tendency to bleed or swelling
-Patients need to be instructed to AVOID CROWDS OR PLACES WEHRE EXPOSURE TO PATHOGENS IS MORE LIKELY BECAUSE THEY ARE IMMUNOSUPPRESSED when taking these drugs
Types of BRMs
MAB = Must Avoid Bugs
Monoclonal Antibodies (Mab drugs)
Interleukin-2 (a cytokine)
Alpha interferon (IFN)
When a MONOCLONAL ANTIBODY attaches to a cancer cell:
Make the cancer cell more visible to the immune system
Block growth signals
stop new blood vessels from forming (blocks angiogenesis)
Deliver radiation to cancer cells
deliver chemotherapy to cancer cells
Adult Cancers
Greater than 99%
environmental cause high
80% can be prevented
found during routine screening exams
intolerant to treatment
less responsive to chemo
Pediatric cancer
Diagnosed during peak growth times
less than 1%
genetic cause, not much environmental
few can be prevented
found accidentally
tolerant to treatment but long term consequences
very responsive to chemo
Teratogens
chemical, biological, or physical factors that might cause an abnormal development of a fetus in the mother’s womb (congenital birth defects)
When are teratogens most effective
First week of pregnancy (all-or-nothing)
-baby either dies from tetratogens or survives without any harm
Three to with weeks of pregnancy
-considered the most critical. Organs start to form and are sensitive to harmful factors
Examples of teratogens
Diseases (maternal illness): chicken pox, herpes, german measels, HIV, AIDS, infections etc.
Drugs/ chemicals: tetracycline, acne medication, aspirin, antacids, diet pills, alcohol, etc.
Environmental: mercury (even small amounts in fish) lead, radiation (like x-rays)
Fetal Alcohol Syndrome
-One drink for mom = ten for the baby
-Harmful effects to the fetus from maternal alcohol use will happen * throughout the pregnancy and is the #1 cause of mental retardation in children
-defects caused by fetal alcohol syndrome irreversible
-Distinctive facial features, including wide set eyes, an exceptionally thin upper lip a short upturned nose and a smooth skin surface between nose and upper lip
Alchohol sydrome in fetal also causes
developmental delays
physical defects
seizures during withdrawl
behavioral problems
intellectual impairment
brain malformation
TORCH infections
perinatal infections account for 2% to 3% of all congenital anomalies
TORCH includes
Toxoplasmosis
Other (syphilis, varicella-zoster, parvovirus B19)
Rubella
Cytomegalovirus (CMV)
Herpes Infections
TORCH causes
Mild maternal morbidity but have serious fatal consequences
Epigenetics
“on top” of genetics
Epigenetic changes are modifications of DNA
*Which occur without any alteration in on or off and how much of a particular message is made
Child abuse has been shown to alter the epigenetic profile of the brain when examined post-mortem
epigenetic changes can also be handed down from mother or father
