Week 14: Oncology Meds Flashcards
Chemotherapy is best for those cancers with a high growth factor. What does this mean?
there ar emore proliferating cells than dying cells
Since chemo is effective on cells with high growth fractions (like cancer), what else can be effected?
High growth fraction normal cells:
Bone Marrow
Hair Follicles
Sperm Forming Cells
GI Epithelium
Solid tumors respond ___ to anti-cancer drugs
poorly (need debulking)
If solid tumors respond poorly to chemo, what does chemo help against?
metastasis or spreading cancer
What kinds of cancers respond best to drug therapy
disseminated cancers (high growth fraction) like leukemia and lymphoma
Why are CNS tumors hard to treat
the BBB prevents drugs from getting where the cancer is
What is the most effective way of tackling cancer via chemo
using multiple agents and attacking at different cell cycle stages
What are some commonly seen effects from anticancer drugs
Bone Marrow Depression (Neutropenia, Thrombocytopenia, Anemia)
Gi Issues
Hair Loss (Alopecia)
Sperm Forming Cell Issues (Sterility)
NV
Hyperuricemia
Vessel Injury from extravasation
Most traditional chemotherapeutic drugs interfere …
either with the synthesis of DNA, RNA, or proteins OR with the appropriate functioning molecules
How do cells die when someone has a chemo agent given
a proportion dies - thats why multiple doses are needed
Cell Cycle Specific Drugs
toxic to the cell at a particular phase and cause no significant harm during other phases
Cell Cycle Non Specific Drugs
kills cells regardless of their phase in the cell cycle - and are considered more toxic but stronger
Targeted Cancer Therapy
Newest chemo drugs that block the growth and spread of cancer by “Harnessing” bodys own immune system
Blocks signals that tell cancer cells to grow and divide uncontrollably
Advantage of Targeted Cancer Therapies
may be more effective and less harmful to normal cells
Prototype Cancer Chemotherapy/Oncology Drugs
9:
Cyclophosphamide (Cytoxan) Methotrexate (Rheumatrex, MTX) Mercaptopurine (Purinethol) Fluorouracil (Adrucil) Doxorubicin (Adriamycin) Vincristine (Oncovin) Cisplatin (Cisplatinum) Paclitaxel (Taxol) Tamoxifen (Nolvadex)
Cyclophosphamide (Cytoxin) Classification
ALKYLATING Chemotherapeutic Agent
Action of cyclophosphamide
Inactivation of DNA (via alkylation)
Binds to DNA to form cross links and prevent DNA, RNA, and protein synthesis
DNA Breakage will occur from alkylation
Is cyclophosphamide cell cycle phase specific or non specific
cell cycle phase non specific
What sort of cancers is cyclophosphamide used in
hematologic cancers and solid tumors
What happens when cyclophosphamide is metabolized by the liver
it turns into the cytotoxic agent against cancer cells (alkylation)
ADRs of Cyclophosphamide
- LEUKOPENIA (major one)
- Thrombocytopenia
- Hemorrhagic Cystitis (High Dose Therapy)
Other - Bone marrow depression, alopecia, amenorrhea, azoospermia, teratogenesis,hyperuricemia, NV
What is the lowest point of bone marrow depression with cyclophosphamide
nadir of WBC is between 9-14 days - most sensitive to infection but neupogen can help counteract this
What is hemorrhagic cystitis and how do we prevent it form occurring when taking cyclophosphamide?
It is bleeding inflamed bladder form high doses
we prevent by giving IV fluids and liberal amounts of fluid intake
What is length of cyclophosphamide therapy guided by?
It is guided by keeping leukocyte count between 3000-4000 mm^3
What other disease does cyclophosphamide help treat
rheumatoid arthritis (lower immune system to help)
Route of cyclophosphamide
IV or oral
Mesnex (Mesna)
a drug to help protect the bladder from high doses of cyclophosphamide
What is the issue with long term cyclophosphamide therapy
secondary cancers can occur like with other chemo drugs
Methotrexate (Rheumatrex, MTX) Classification
Antimetabolite Chemotherapeutic Agent ; Folate Antagonist
Action of Methotrexate
inhibits folic acid reduction, thereby interfering with synthesis of the coenzyme needed for DNA synthesis
S phase specific
Is methotrexate cell cycle phase specific or non specific
specific (S Phase)
Route of Methotrexate
Oral - for routine doses
IM - large doses
ADRs of Methotrexate
- STOMATITIS
- PULMONARY INFILTRATES AND FIBROSIS (In Lungs) (can permanently effect resp fxn)
Other: Leukopenia, Thrombocytopenia, Hepatotoxicity, NV, Alopecia, Tubular Necrosis (In Kidneys), HA, Gingivitis, Alopecia
What other disease can methotrexate be used on and why
Rheumatoid Arthritis - strong immunosuppressive effects inhibiting T Lymphocytes
Can also be used in Chrohns Disease soemtimes
Methotraxate is an anti-metbolite. What does this mean
it looks like folic acid to the body but is not
it will antagonize the receptors to stop cell DNA synthesis
Leucovorin
“Rescue” Folinic Acid
It is an antidote for methotrexate that can save normal body cells
Mercaptopurine (6-MP, Purinethol) Classification
Antimetabolite, Chemotherapeutic Agent, Purine Analog
Action of 6-MP / Mercaptopurine
Inhibits DNA synthesis by preventing purine incorporation into the DNA (antagonist)
S Phase Specific
Is 6-MP/Mercaptopurine cell cycle phase specific or non specific
Specific (S Phase_
Route of 6-MP/Mercaptopurine
Oral - Readily
IV - an option
ADRs of 6-MP/Mercaptopurine
- BONE MARROW DEPRESSION (Neutropenia, Thrombocytopenia, Anemia)
- JAUNDICE
Other: NV, anorexia, leukopenia, hyperuricemia
Why do patients on 6-MP/Mercaptopurine develop Jaundice
It reflects liver damage
30% of patients on this drug develop hepatic dysfunction
Fluorouracil (5-FU, Adrucil) Classification
Antimetabolite, Chemotherapeutic Agent, Pyrimidine Analog
Action of Fluorouracil/5-FU
Affects specific steps in pyrimidine (Not purine) metabolism leading to inhibition of DNA and RNA synthesis
S Phase Specific
Is 5-FU/Fluorouracil cell cycle phase specific or non specific
Specific (S Phase)
What sort of cancer is 5-FU/Fluorouracil used for
solid tumors, esp. malignant GI tymors - can be used for other stuff as well though
Route of 5-FU/Fluorouracil
IV (Oral is too unpredictable)
ADRs of 5-FU/Fluorouracil
- MYELOSUPPRESSION (Anemia, Leukopenia, Thrombocytopenia) (Nadir 9-14 days)
- GI ULCERS
- ALTERATION IN TASTE
Other: Stomatitis, Diarrhea, Anorexia, NV, Alopecia, hand and foot syndrome
What is the alteration in taste like with 5-FU
aversion to protein foods
What are special situations for 5-FU/Fluorouracil use
PALLIATIVE TX: Breast, Colon, Rectal Cancer (Solid Tumors)
GI, Ovarian, bladder, Prostate, Pancreatic Carcinomas
Direct Hepatic Artery infusion for Liver Carcinoma or Metastasis
What does antibiotic mean
one organism against another
its not just for infection - some products of streptomyces can help tx cancer
Doxorubicin HCI (Adriamycin) Classification
Antibiotic Antitumor Agent ; Anthracycline
Action of Doxorubicin HCl
Distorts DNA structure so synthesis of DNA and RNA is inhibited
Is Doxorubicin HCl Cell cycle phase specific or nonspecific
non specific
Route of Doxorubicin HCl
mostly given as IV infusion
ADRs of Doxorubicin HCl
- ACUTE AND DELAYED CARDIOTOXICITY (dysrhythmias, EKG changes, cardiomyopathy, CHF and death)
- SIGNIFICANT BONE MARROW DEPRESSION
- RED/ORANGE URINE/TEARS
Other: Alopecia, NV, Stomatitis, Local Extravasation Risk
What is important about the dosage of Doxorubicin HCl
once a person reaches maximum dosage they cannot have anymore and there needs to be careful calculation and administration due to the RISK FOR HEART DAMAGE that is great
How is the bone marrow depression worse in Doxorubicin HCl
the neutropenia occurs at day 7 (earlier than most)
What kind of cancers is Doxorubicin HCl used in
solid tumors or disseminated cancer
Why does red colored food cause NV and anorexia with patients on Doxorubicin HCl
The drug is a dark cherry kool aid red color
This even turns your urine and tears red orange or red pink
Doxorubicin HCl is a severe vesicant, what implication does this have on a patient
A vesicant can damage tissue permanently and since it is given IV, extravasation can lead to severe pain and tissue damage permanently (can lessen with an implanted port)
Vincristine (Oncovin) Classification
Chemotherapeutic Agent; Vinca Alkaloid
Action of Vincristine
binds specifically with the protein TUBALIN, part of cell microtubules
Blocks mitosis during metaphase so it is M phase specific and STOPS CELL DIVISION / MITOSIS
Is Vincristine Cell Cycle Phase specific or non specific
Specific (M Phase)
Route of Vincristine
IV (Oral unpredictable)
ADRs of Vincristine
- NEUROTOXIC (peripheral neuropathy, muscle weakness, loss of deep tendon reflexes, HA, vocal cord paralysis, ptosis, diplopia, paralytic Ileus)
Other: GI disturbances, alopecia, only mild bone marrow depression
What is unique about vincristine and bone marrow
it only causes mild bone marrow depression - to the point it is considered bone marrow sparring compared to other chemo drugs and thus can be used alongside them
Vincristine is a ____ and can damage surrounding tissues
Vesicant
What is vincristine very effective at doing in children
inducing remissions in acute leukemias
Cis-Platinum (Cisplatin) Classification
Heavy Metal Chemotherapeutic Agent
Action of cis-platinum
inhibits DNA precursors, maybe via alkylating effect
Is cis-platinumcell cycle phase specific or non specific
Non Specific
route of cis-platinum
ORAL, IV is ineffective
ADRs of cis-platinum
- SEVERE NV
- NEPHROTOXICITY
- OTOTOXICITY
Other: Mild and transient bone marrow depression, peripheral neuropathy (tingling, numbness in fingers, toes and face)
How ototoxic is cis-platinum
enough to cause loss of high frequency hearing
What must be given alongside cis-platinum
other drugs such as anti-emetics to prevent potential significant side effects
Since cis-platinum is a heavy metal, what must be done
a “mannitol flush” must be given before and after to prevent acute tubulular necrosis of the kidneys - get it moving through to prevent pain
Paclitaxel (Taxol) Classification
(newer) Chemotherapeutic Agent (Taxane Family)
Action of Paclitaxel
Inhibits normal dynamic reorganization of the microtubule network needed for vital mitotic cell fxns
(G2 and M phase specific)
So it works in prepartion for Mitosis causing problems there but begins working before that phase
Is paclitaxel cell cycle phase specific or non specific
specific (works in G2 and M phase)
Route of paclitaxel
IV
ADRs of Paclitaxel
- SEVERE HYPERSENSITIVITY RXNs
- PERIPHERAL NEUROPATHY / NEUROTOXICITY
- MYELOSUPPRESSION
Other: bone marrow suppression (nadir of 11 days), CV bradycardia/heartblock/MI, arthralgia, GI NV/diarrhea/mucositis, alopecia, change in liver fxn
What is unique about the alopecia with paclitaxel
it is very sudden and comes out in clumps
Hypersensitivity reactions occur in __% of paclitaxel patients and needs what prior?
10%; pre medication with corticosteroids, diphenhydramine, and H2 antagonists
Paclitaxel should not be given when
with neutrophil counts of <1500
What sort of cancers may have paclitaxel given
ovarian
lung
breast
other
Taxmoxifen (Nolvadex) Classification
Antiestrogen (competitive antagonist) , SERM (Selective Estrogen Receptor Modulator)
Action of taxmoxifen
Competitive antagonist of estrogen
Binds to estrogen receptors to prevent stimulation of the receptors by estradiol (naturally occurring estrogen)
Because of this the estrogen cannot feed the cancer
Route of taxmoxifen
oral
ADRs of taxmoxifen
MOST NOT TROUBLESOME - TOLERATED WELL:
- MENSTRUAL IRREGULARITIES
- BONE PAIN (positive sign not bone cancer)
- ENDOMETRIAL CANCER POTENTIAL
Common: NV, Hot flashes
Other: Pruritis vulvae, increased tumor pain
What is the most widely prescribed anti-cancer agent in the world
taxmoxifen
What is taxmoxifen used for
to treat AND prevent breast cancer in high risk women (Adjunct to radiation, chemo and surgery)
What is needed for taxmoxifen to be effective
the target tumor cells must be estrogen receptor (ER) positive
Since taxomoxifen is a SERM, what effects may it have other than prevent tumor growth?
Agonist effects on tissues like the uterus, bone, and some other areas
Antagonist effects in areas like the breast
What does the agonist effect of SERMs like taxomoxifen lead to in bone and the uterus
Uterus - Endometrium Cancer potentially
Bone - Bone pain (good though sign)
What is the max amount of time taxmoxifen is used and why
5 years - want to prevent causing endometrial cancer