WEEK ONE - NEOPLASMS + CANCER (Aine) Flashcards
Benign tumour characteristics
Looks similar to the surrounding tissue.
Grows by expansion
Recurrence minimal, prognosis good
Bad: location can affect body
Malignant tumour characteristics
Cells look very different
Grow by infiltration, invasion, and metastasis (blood + lymph)
Affects whole body: loss of appetite, cachexia, anemia, N/V, etc etc
Prognosis poor if untreated, recurrence common.
Proto-oncogene
normal genes; turned off
oncogenes
turned on proto-oncogene; mutate and proliferate cancer
what turns on a proto-oncogene?
1) Viruses (e.g. HIV and Kaposi’s sarcoma)
2) DNA damage to tumor suppressant sections of genes
Tumor suppressant genes to know
Rb gene: “master brake”
P53 gene
BRCA1 and BRCA2
Three stages of carcinogenesis
1) initiation
2) promotion
3) progression
Initiation
tumor formation
oncogenes turned on OR carcinogens
Promotion
“feeds” cancer – risk factors (smoking, air pollution, sexual activity)
Progression
point at which cancer becomes malignant. not all cancers get to this point.
3 patterns of cancer spread
1) direct local spread
2) seeding
3) metastatic growth
Direct local spread
Invasion of surrounding tissue
Seeding
Cell goes through a cavity
During surgery for tumor removal, a few cells are dropped elsewhere
Metastatic growth
w/ escape enzymes, cancer spreads through blood or lymph.
Most common sites of m. growth are Liver and Lungs
other sites: bone, brain, adrenal glands
General physiological response to cancer
bleeding/hemorrhage
anemia
cachexia, loss of appetite, weakness, wasting of tissue
tumor markers
enzymes found in secretions that may tell us where the tumor could be
angiogenesis
formation of new blood vessels. tumors need blood to grow and thus induce angiogenesis in the body
cancer warning signs
changing bowel/bladder habits, open and unhealing sore, unusual bleeding/discharge, lump/mass, indigestion and difficulty swallowing, obvious change in wart/mole, nagging cough/hoarseness
cancer warning signs in children
Unexplained weight loss, headaches w vomiting in the morning, swelling/pain in bones/joints, lump/mass, whitish-looking pupil, recurring fevers, excessive bleeding or bruising, paleness and tiredness
three levels of prevention
Primary (life habits), Secondary (screening), and Tertiary (treating)
Why do we perform screening tests?
early detection = higher survival
examples of screening tests
Annual physical exams
PAP smear (cervical tissue)
Breast Self Exam or yearly mammogram
Testicular Self Exam
Prostrate Screening and Digital Rectal Exam
treatment options are based on…
based on realistic and achievable goals for each specific type of cancer. Range includes cure, control, and palliation.
This includes surgeries, chemotherapy, and radiation.
surgical options for cancer
Prophylaxis: removal of something to prevent cancer from developing.
Primary (curative): remove primary site & lymph nodes when tumor is small & well differentiated.
Palliative: removal of tumor pressing on nerve
Reconstructive: breast, head, neck
Debulking: removal of the bulk of the tumor; should be performed before the start of chemotherapy whenever possible
Resection of Metastases: used only in selected cases when a cure can be obtained or a reasonable prolongation of survival is possible. Primary cancer must be under control
Chemotherapy is primarily for…
primarily for systemic disease.
Often how many drugs are given?
Antineoplastic drugs are often given in combination to target different parts of the cell cycle
Side effects of antineoplastic drugs
Anorexia, loss of taste/aversion to food, erythema, painful ulcerationof mucous membranes
Nausea/vomiting
Cachexia (debilitation)
Hair loss → alopecia (not permanent)
Stomatitis/mucositis (inflammation – pain, bleeding, sore throat, open sores; d/t direct irritating effects of the drugs that impact normal as well as cancer cells)
Bone Marrow Depression - Neutropenia (loss of WBC; more susceptible to infections), Anemia, Thrombocytopenia
Radiation Therapy
high-energy ionizing beams interrupt cell growth. The goal is to deliver a precise dose of ionizing radiation for maximum tumor cell kill without affecting healthy tissue.
radiosensitive tumours
Only effective on tumors directly within the path of radiation
Radiosensitive tumors include: bone marrow, lymphomas, epithelial, (also prostate, testicular, cervical)
S/E of radiation
headaches, hair loss, nausea/vomiting, fatigue, hearing loss, memory and speech issues, skin and scalp changes.
Lethal Dose (radiation)
eradicate 95% of the tumor yet preserve normal tissue
Why fractionated doses (radiation)?
delivered over several weeks to allow healthy tissue to repair and to achieve greater cell kill by exposing more cells to the radiation as they begin active cell division
fractionated doses increase radiosensitivity of tumour
