cancer Flashcards
cancer
characterized by uncontrolled and unregulated growth of cells
pathophysiology of cancer
- divide indiscriminately and haphazardly
- proliferate at the same rate as the normal cell tissue from which they originate
3 steps of cancer
- initiation
- promotion
- progression
initiation (step 1) of cancer
mutation occurs in a cell’s DNA leading to activation of oncogenes or inactivation of tumor suppressor genes
promotion (step 2) of cancer
mutated cells undergo continual, unregulated proliferation forming a small cluster of abnormal cells
progression (step 3) of cancer
abnormal cells continue to divide and grow forming a tumor
oncogenes
genes that promote cell growth
benign neoplasm tumors
- well differentiated
- encapsulated
- expansive mode of growth
- metastasis absent
- rarely recur
malignant neoplasm tumors
- usually undifferentiated
- able to metastasize
-infiltrative and expansive growth - frequent recurrence
- moderate to marked vascularity
- rarely encapsulated
- becomes less like parent cell
immunological surveillance
- lymphocytes check cell surface antigens and destroy abnormal cells
- cytotoxic T cells kill tumour cells
- natural killer cells and activated macrophages lyse tumour cells
- B cells produce antibodies directed to tumour surface antigens
immunological escape (mechanisms in which cancer cells evade immune system)
- suppress factors that stimulate T cells
- weak surface antigens allow cancer cells to “sneak through”
- immune system tolerance by some tumour antigens
- suppress immune response from products secreted by cancer cells
- induction of suppressor T cells
- blocking antibodies bind tumour-associated antigens preventing recognition
origin of cancer
- genetic
- chemical
- environmental
- viral or immunological
main sites of metastasis
- brain and cerebro-spinal fluid
- lung
- liver
- adrenals
- bone
anatomical site classification of tumours
- tissue of origin
- embryonal ectoderm (skin, glands)
- endoderm (mucous membranes)
histological classification of tumours
- appearance of cells
- poorly differentiated tumours have a worse prognosis
grade I cancer
- cells differ slightly from normal
- well differentiated
grade II cancer
- moderate dysplasia and differentiation
- limited local spread
grade III cancer
- abnormal cells
- poorly differentiated
- extensive local and regional spread
grade IV cancer
- cells are immature, primitive and undifferentiated
- cell of origin is difficult to determine
- metastasis
TNM cancer classification system
- tumour size and invasiveness (T)
- spread to lymph nodes (N)
- metastasis (M)
lung cancer
- insidious and often asymptomatic until late in its course
risk factors
- tobacco
- environmental and occupational factors
- genetics
- dietary (low fruits and veggies)
lung cancer : non-small cell carcinoma (NSCC)
- 87%
- adenocarcinoma (38%)
- squamous cell (20%)
- large cell (5%)
lung cancer : small cell carcinoma
- 13%
CM of lung cancer
- cough
- dyspnea
- blood-tinged sputum
- recurrent chest infections
- wheezing
- chest and shoulder pain
- palpable lymph nodes
lung cancer assessment
- chest xray
- CT
- sputum cytology
- bronchoscopy
- needle aspiration
- scans for metastases
dx of cancer
- health history
- identification of risk factors
- physical exam
- specific diagnostic studies
bronchoscopy
- visualizes tracheobronchial tree
- used for dx sampling and therapeutic interventions (lavage, balloon dilation)
cancer tx
- surgery
- radiation
- chemotherapy
- palliation
chemotherapy
- inhibits synthesis of cellular enzymes
- hinder DNA replication
- induce cell damage and apoptosis
classification of chemo medications
- target different stages of cell cycle
- some damage cells at point of splitting
- some damage cells while they make copies
effects of chemo on normal tissue
- can kill/slow growth of healthy cells that grow and divide quickly (ex. cells that line the mouth, intestines, cause hair growth, bone marrow)
chemo tx plan
- few hours-days
- every week or in intervals
nadir
lowest amount of WBC that a person reaches following each chemo cycle
cisplatin
- chemo drug used to tx testicular, ovarian, bladder, head, neck, lung, and cervical cancer
MOA
- ability to crosslink with purine bases on DNA
- interfering with DNA repair
- causing DNA damage
- inducing apoptosis in cancer cells
side effects
- ototoxicity
- hepatotoxicity
- gastrointestinal toxicity
- hematological toxicity
- retinal toxicity
- cardio toxicity
- neurotoxicity
- nephrotoxicity
etoposide
- chemo drug used in management and tx of testicular, prostate, bladder, stomach, lung cancer
MOA
- kills cells by stabilizing enzyme-cleaved DNA complex that is a transient intermediate in the catalytic cycle of topoisomerase II
side effects:
- infection
- anemia
- bruising, bleeding
- n&v
- sores in mouth
- hair loss
radiation
- kills cancer cells by using beams of high energy
- tx daily, 5 days a week for 5-8 weeks
- goals of therapy: curative, shrink tumours
palliation
- may include radiation
- pain management and comfort measures
- evaluation
- hospice referral
nursing management chemo induced n&v
- antiemetics
- lifestyle management (eat foods they feel like eating, avoid strong smells, avoid warm food, eat smaller meals more frequently)
psychological care
- support pt and family
- awareness of behavioural patterns
- facilitate development of a hopeful, realistic attitude about cancer
