Lecture 43- Intro to clinical oncology Flashcards
Define the Following:
Cancer
Carcinoma
Sarcoma
Cancer - Neoplasm (“new growth”)
Carcinoma - derived from epithelial tissues
Sarcoma – derived from mesenchymal tissues
What type of cancer has the highest mortality?
What type of cancer has the highest incidence (morbidity) men vs women?
Mortality: Lung cancer
Followed by prostate (men), breast (women), and colo-rectal (both)
Morbidity:
Men - prostate
Women- breast
Describe the Presentation of Solid Tumors?
Local – Interference with normal organ function (such as bowel obstruction) vs extension into adjacent structures (such as CP from a lung mass)
Metastatic Symptoms – bone pain, seizures, headache
Paraneoplastic Syndromes - eg cushing’s symptoms from an ACTH secreting tumor
Incidental or Screening – asymptomatic
Describe the presentation of Hematologic malignancies?
Bone Marrow Failure - anemia, thrombocytopenia, leucopenia
Bone Marrow Proliferation – thrombosis, luekocytosis, splenomgaly
LAD, Thrombosis – altered function of bone marrow derived cells
Constitutional Symptoms – fevers, night sweats, weight loss
What is performance status? how is it measured? why is it significant ?
Ability of the patient to do things
Scales: Karnofsky, Eastern Cooperaitve Oncology Group
0 - No limitations; 5 - dead
Poor perfomance status — indicator that patient will not respond as well to treatment
What directs the treatment of cancer?
TMN Stating + other factors (patient performance status and patient preferences)
What are the classifications of disease that direct treatment?
how are they treated?
- Localized Disease – Confined to tissue or origin, no invasion of adjacent structures; —- Surgical, Radiation
- Locally Advanced – regional LN involvement, large tumors — Use of systemic therapy in combo with local therapies to improve outcomes from localized treatment
- Systemic Therapy for Advanced Disease – Chemotherapy, hormonal, immunotherapy, rad/surg to symptomatic relief
What is the aim of radiation therapy?
○ AIM OF THERAPY: deliver as uniform a dose as possible to an accurately localized target; killing tumor cells with minimizing physical, physiological and psychological consequences to the patient
what is the unit to quantify radiation ?
what type of radiation must be used to to induce DNA damage?
what type of DNA damage is lethal?
Gray – (J/Kg)
1 gray = 100 cGy
1cGy = 100 Ergs/gram = 1 Rad
Ionizing radiation
DNA Double stranded breaks
Why are tumor cells more susceptible to ionizing radiation?
rapid proliferative tumors are more susceptible because of mitotic phases
Tumors are more susceptible bc of defects in DNA repair
What normal tissues are most sensitive to toxic effects of radiation therapy? which are not as sensitive?
High Sensitive – thyroid, lung, bone marrow, lining of colon
Low - bone, skin, gall bladder, kidneys
What are some acute and late side effects of radiation therapy?
Side Effects
Acute – Erythema, Epilation, desquamation, Re-epitheliazation
Late effects — atrophy, fibrosis, Necrosis, telangiectasia
Local Dysfunction: Stenosis, necrosis, fibrosis
Potential occurrence of Second Tumors
What factors determine the probability of long term toxicity?
○ Chances of Long term Toxicity
○ Dose
○ Fraction size – larger individual doses
○ Volume Treated
○ Nature of the cell Treated
○ Organization of the Tissue
□ Oxygen Content – -O2 interacts with the radiation and can form free radicals
Describe the dose profiles between Wave form radiation and particle radiation?
what is the significance ?
X rays – wide
Particle: Protons and carbon ions – narrow deposition range. Only at specific doses do they have deeper penetration
what are the forms of radiation delivery?
External Beam Radiation — aka Teletherapy
Brachytherapy – radioactive source administerd close to the tumor
Systemic – administer isotopes to circulation
Such as Radioactive Iodine
Radio-immunotherapy – isotopes attached to antibody
