Lecture 5 - Cancer chemotherapy by hisham Flashcards
Describe the cell cycle.
G0 phase
Most cells spend much of their lives at this stage. It is also known as the resting stage. Depending on the cell type, the cell can spend from few hours to few years in G0 phase. It will move to G1 phase if it receives a signal to reproduce.
G1 phase
The cell start making more proteins and growing larger so that the new cells will be normal size. This phase can last 18 to 30 hours
S phase
The chromosomes containing the DNA are copied so that the new cells will have matching strands of DNA. This stage last 18 to 20 hours
G2 phase
The cell checks the DNA and get ready to split into 2 cells. This phase last 2 to 10 hours.
M phase (mitosis)
The cell split into 2 new cells. It can last 30 to 60 minutes.
What patient factors are considered while planning a chemotherapy?
- Elderly, renal and liver function
- Nutritional status, PMH
- Obesity, volume of distribution
- Drug-drug interactions
- Adjuvant, combination or radiotherapy
- Full blood count
How to calculate biological half life.
t1/2 = 0.693/K ea
K ea = apparent elimination rate.
List the different types of targeted parenteral chemotherapy.
Intra-arterial - injected into an artery that goes to the tumour
Intravesical- injected into the bladder
Intrapleural - injected between the chest and lung
Intrathecal - when the drug needs to reach the cerebrospinal fluid because of BBB
Intraperitoneal - Injected directly into the abdominal cavity.
What are the limitations of oral anticancer drugs?
Cost
Bioavailability due to size, pH, solubility)
Adherence due to side effects
Interaction with other medicines.
List the parenteral route available for chemotherapy.
IM chemo injections (not for low platelet patient, normally antiemetics)
SC chemo injections (for a biologic response modifiers or chemo support drugs, less risk of bleeding.)
IV chemo treatment ( can be used for very slow delivery from hours to few weeks, 100% bioavailable)
What is an angiocatheter or a centeral line?
It one of the ways for IV administration which is done in a vein in the arm or hand and removed after drug is given. Can last few minutes to days.
What is a PICC line?
It involves the insertion of a long catheter into one of the larger veins of the arms which can be used for 6 weeks to few months.
What is a tunneled or non-tunneled catheter?
These are placed through the chest to the vena cava vessel. It is used for a more extensive treatment such as bone marrow transplant.
What is a Port a cath?
It is a more permanent way for delivery as a port a cath is inserted under the skin on the chest and the catheter is inserted in the vena cava at the entrance of the right atrium.
