Week 12 cancer - pharm Flashcards
What are the 6 barriers to chemo success?
- we don’t know when 100% of cells are killed
- drug resistance over time* most common cause*
- solid tumors don’t respond to chemo as well because of low growth fraction
- killing every malignant cell is almost impossible
- Kill both cancer and healthy cells
- Dosage is limited to the risk of toxicity to normal cells
What are 4 strategies for chemo success to optimize chemo results?
- Intermittent therapy
- Combination therapy
- Optimizing dose schedules
- regional drug delivery to the exact area and not systemic
What are the 6 major chemotherapy toxicities (consequences)?
- bone marrow suppression
- Digestive tract dysfunction
- alopecia
- reproductive toxcitiy
- local injury - Extravasation of Vesicants
- carcinogenisis
What type of cancer is surgery good for?
Solid and localized tumors
What is radiation good for?
Solid and localized tumors
What is chemo drug therapy good for?
Disseminated cancers
What does disseminated cancers mean?
They have spread throughout an organ or the entire body
What are the 3 examples of disseminated cancers?
- Lymphoma
- Leukemia
- Metastises cancers
What are the 4 major drug therapies for cancer ?
- Cytotoxic Agents (Chemotherapy)* most common*
- Hormones and Hormone Antagonists
- Biologic Response Modifiers
- Targeted Drugs
What is the main job of cytotoxic agents (chemotherapy)
Kill malignant cells
What is the main job of hormone and hormone antagonist drugs?
Stop cancer that uses hormones to grow
What is the main job of Biologic response modifiers (immunotherapy) ?
-Treat cancer by adding or changing body process already present (ie) enhance immunity
- Help with toxicities caused by some cancer drugs
What is growth fraction?
- explains why some tissues in the body are more prone to toxic chemo effects
- Cells in active proliferation phase and have high growth fraction will be killed more quickly
- cells in inactive G0 stage have a low growth fraction and are killed more slowly
Does cytotoxic chemo have a greater affect on high growth fraction cells or low growth fraction cells?
High growth fraction cells
What are examples of high growth fraction cells?
- bone marrow
- GI epithelium
- hair follicles
- sperm forming cells
What phase do cytotoxic drugs affect?
Active phase
disrupts DNA synthesis or Mitosis
Which cancers do not respond the best to chemotherapy (cytotoxic drugs) because they have a low growth fraction?
1.breast
2.colon
3.rectum
4.prostrate
5.lung
What cancers do respond better to chemo (cytotoxic) drugs because they have a high growth fraction?
leukemia
lymphoma
testicular cancer
What is the goal of chemotherapy?
Kill 100% of Neoplastic/malignant/cancer Cells while causing limited injury to normal tissues.
What is the most common cause of treatment failure in chemotherapy?
- drug resistance over time
What are the main treatments for solid tumors and why
- surgery - because they don’t respond well to chemo and you want to try to get it out
- chemo (adjunct) to kill any remaining cells left behind and prevent growth again
What is intermittent chemo therapy?
Think chemo rounds
- try to kill 100% and limit death of good cells
- give time for normal cells to repopulate but they have to do it faster than the malignant cells
- if the malignant cells grow just as fast as healthy ones then it will fail
What is combination chemo therapy and what are the 3 advantages?
Combine 2 or more chemo drugs
1. Reduce resistance and increase success
2. Increases overall cancer kill rate – MOA combo kills cells in more ways
3. Reduce toxicity to normal cells – especially if they don’t have overlapping toxicities
Why is optimizing dosing schedules important?
- to kill as many malignant cells as possible while maintaining healthy cells
What is regional drug therapy?
- Intra-artierial delivery - brain/liver artery
- intra-thecal delivery - bladder or peritoneal cavity
- Localizing it helps avoid systemic side effects
How do we know if someone is experiencing Anemia from a reduction in RBC from suppression of bone marrow (myelosuppression)
- SOB
- Fatigue
- Pallour
How do we know if someone is experiencing Neutropenia from a reduction in WBC from suppression of bone marrow (myelosuppression)
- Infection
How do we know if someone is experiencing thrombocytopenia from a reduction in platelets from suppression of bone marrow (myelosuppression)
- bleeding - low BP, high HR, weak
- bruising - petiche , ecchymosis
- GI bleeds - hemesis, occult/blood in stool
What is one of the most significant dangers of chemo drugs?
Infection due to suppression of WBC in bone marrow - can lead to sepsis
What measurement is Neutropenia?
<500mm3
How many days do we see a dip in Neutrophil levels?
2-3 days
When are patients most at risk of life threatening infection ?
Nadir
day 10-14
Why is Nadir so dangerous?
because the signs of infection are masked/not present
- > or = 38.0 (low grade fever) may be the only sign
What temp is considered low grade fever for chemo patients and signifies an emergency?
> or =38.0
What is the main sign of infection for someone with Nadir?
Fever
What are Hematopoietic Growth Factors also known as?
Colony Stimulating Factors
Biologic response modifiers
What are hematopoietic growth factor/colony stimulating factor/biologic response modifiers used for?
the effects of bone marrow suppression (myelosuppression)
1. neutropenia
2. thrombocytopenia
3. anemia
what makes stem cells turn into RBC, WBC or platelets from the bone marrow?
hematopoetic growth factor that tell the body which cell to make
What are the 3 categories of biologic response modifiers?
- Erythropoetin (RBC)
- Leukopoietic
- Thrombopoietic
Why can’t Epo be given to patients with myeloid malignancies and leukemias?
Because those are blood cancers and we could create more cancer growth of RBC
What drug can we never give PO?
Epo
What are the side effects of EPO? think thicker blood- clotting
- stroke
- heart failure
- MI
- blood clots
Who should EPO not be given to and why?
anyone who is not palliative because it can cause tumor growth and shorten life span
What is positive use of Epo?
to help increase quality of life for palliative patients experiencing the affects of anemia
what class is Filgrastim (Neupogen)?
Leukopoetic growth factor
What does Filgrastim (Neupogen) do?
increase neutrophil growth and help lower infection
Who should likely not receive Filgrastim (Neupogen)?
People who have bone marrow cancer because we don’t want to proliferate cancer cells
Does Filgrastim (Neupogen) have many side effects?
no
more commonly used
What drug class is Oprelvekin (Neumega)?
thrombocytopoetic growth factor
What does Oprelvekin (Neumega) do?
promotes platelet growth from stem cells in the bone marrow
What type of patients does Oprelvekin (Neumega) help?
those with thrombocytopenia and to help avoid needing a platelet blood transfusion
What cytokine does Oprelvekin (Neumega) look like in the bone marrow?
Nearly identical to Interleukin-11, a cytokine produced in the bone marrow
What is stomatitis?
inflammation of the oral cavity
how many days after starting chemo can stomatitis develop?
2-3 days (high proliferatin)
How long can stomatitis continue after treatment stops?
up to 2 weeks after
What can stomatitis cause in terms of symptoms?
- pain
- infection
- inflammation to ulceration
What are the 3 characteristics of bone marrow suppression in a chemo cancer patient?
- Neutropenia
- Thrombocytopenia
- Anemia
What are 3 characteristics of Digestive tract dysfunction in a chemo cancer patient?
- Stomatitis
- Diarrhea
- Nausea & vomitting
Why do people on chemo drugs experience diarrhea?
destruction of high proliferation epithelial cells in the GI tract
impacts absorption of nutrients and fluids
can lead to infection because skin is not great