supportive and palliative care Flashcards
what are the emesis pathways for CINV
peripheral emesis pathway: predominantly acute phase of CINV
central emesis pathway: predominantly delayed phase of CINV
what are the types of CINV
acute
- occurs 1-2hrs after administration, peak 5-6hrs, resolution in 12-24hrs
delayed
- peak at 48-72hrs after chemotherapy, diminishing in 1-3days
breakthrough
- N/V despite preventive treatment
anticipatory
- N/V prior to chemotherapy
- conditioned response
refractory
- N/V in subsequent cycles when antiemetic prophylaxis or rescue therapy has failed in previous cycle
what are the chemotherapy agents associated with high emetic risk and what is the frequency of emesis (IV)
frequency >90%
- anthracycline and cyclophosphamide
- carboplatin AUC ≥4
- cisplatin
- carmustine >250mg/m2
- cyclophosphamide >1500mg/m2
- doxorubicin ≥60mg/m2
- dacarbazine
- epirubicin ≥90mg/m2
- ifosfamide ≥2g/m2
- mechlorethamine
- streptozocin
what are the chemotherapy agents associated with moderate emetic risk and what is the frequency of emesis (IV)
frequency 30-90%
- aldesleukin ≥10-12 million IU/m2
- amifostine >300mg/m2
- arsenic trioxide
- azacitidine
- bendamustine
- busulfan
- carboplatin AUC <4
- cyclophosphamide ≤1500mg/m2
- carmustine ≤250mg/m2
- doxorubicin <60mg/m2
- daunorubicin
- dactinomycin
- dinutuximab
- epirubicin ≤90mg/m2
- ifosfamide <2g/m2
- idarubicin
- IFN alpha ≥10 million IU/m2
- irinotecan
- melphalan
- MTX ≥250mg/m2
- oxaliplatin
- temozolomide
- trabectedin
what are the chemotherapy agents associated with low emetic risk and what is the frequency of emesis (IV)
frequency 10-30%
- Ado-trastuzumab emtansine
- Aldesleukin ≤12million units
- Amifostine ≤300mg/m2
- Belinostat
- Blinatumomab
- Brentuximab
- Cabazitaxel
- Cytarabine 100-200mg
- Doxorubicin (liposomal)
- Docetaxel
- Gemcitabine
- 5FU
- Etoposide
- Paclitaxel
- Pemetrexed
- Topotecan
what are the chemotherapy agents with minimal emetic risk and what is the frequency of emesis (IV)
frequency <10%
what are the risk groups for IV chemotherapy agents
high, moderate, low, minimal
what are the risk groups for PO chemotherapy agents
moderate to high, minimal to low
what are the chemotherapy agents associated with moderate to high emetic risk and what is the frequency of emesis (PO)
frequency ≥30%
what are the chemotherapy agents associated with minimal to low emetic risk and what is the frequency of emesis (PO)
frequency is <30%
what are the patients risk factors to be assessed
- younger age (<50yo)
- female
- history of low prior chronic alcohol intake (<1 glass)
- history of motion sickness
- history of emesis during pregnancy
- history of previous chemotherapy-induced emesis
- anxiety
what are the antiemetic combinations and elaborate on each combination
for high emesis risk
acute antiemetics: NK1 + 5HT3 + DEXA +/- OLA on d1
delayed antimetics: DEXA on d2-4 +/- OLA on d2-4 (depending if given as acute)
*note NK1 has dosings for d1-3
for moderate emesis risk
acute antimetics: 5HT3 + DEXA on d1
delayed antiemetics: DEXA on d2-3
for low emesis risk
acute antimetics: 5HT3 or DEXA or DOPA
what are the agents used as antiemetics and dosings
NK1 anatagonist
- aprepitant PO 125mg OD on d1 f/b 80mg OD on d2-3
5HT3 antagonist
- ondansetron IV/PO 8-16mg OD on d1
- granisetron IV/PO 1mg OD on d1
NK1- and 5HT3- antagonist combination
- netupitant 300mg + palonosetron 0.5mg (akynzeo) 1 capsule OD on d1
dexamethasone
- IV/PO 12mg OD on d1 f/b IV/PO 8mg OD on d2 onwards
DA antagonsit
- IV/PO metoclopramide 10mg OD-TDS
what is place in therapy of NK1 antagonists
NK1 antagonists like Aprepitant and Netupitant works to prevent acute and delayed CINV by binding to neurokinin-1 receptors and prevent substance P, a nociceptive neurotransmitter, from binding, thus attenuating vagal signals and exert antiemetic effects
- vagal nerve is important in regulation of involuntary bodily functions like HR, digestion and RR
- afferent as the nerve signals are moving towards the brain
dose
- Aprepitant 125mg PO OD on d1 f/b 80mg PO OD on d2-3
- Netupitant 300mg in combination with Palonosetron 0.5mg in a Akynzeo capsule on d1
s/e
- low frequency of nausea, fatigue, weakness and hiccups
drug interactions
- steroids
- warfarin
- BZP (decrease metabolism of BZP)
- ifosfamide (decrease metabolism of ifosfamide)
what is the place in therapy for 5HT3 antagonist
5HT3 antagonists like Ondansetron, Granisetron and Palonosetron works to prevent acute CNIV by binding to and blocking 5HT3 receptors peripherally in the GI tract and centrally in the medulla
dose
- IV/PO Ondansetron 8-16mg OD on d1 f/b 8mg BD on d2 onwards
- IV/PO Granisetron 1mg OD on d1 f/b 1mg OD on d2 onwards
- PO Palonosetron 0.5mg in combination with Netupitant 300mg in an Akynzeo capsule on d1
s/e
- HA, constipation
- may cause QTc prolongation
what is the place in therapy for dexamethasone
dexamethasone prevents acute and delayed CINV by unknown MOA but may be partially due to its activity in the CNS
dose
- IV/PO 12mg Dexamethasone on d1 f/b IV/PO 8mg on d2-3 for moderate emetic risk, d2-4 for high emetic risk
s/e
- more commonly transient elevations in glucose, insomnia, gastric upset, anxiety
- less commonly psychosis and reactivation of ulcers
what is the place in therapy of olanzapine
olanzapine is an atypical antipsychotic useful for prevention of acute and delayed CINV through antagonism of multiple receptors associated with CINV - dopamine, serotonin, histamine, cholinergic
dose
- 5-10mg OD, 2.5mg OD in elderly
s/e
- fatigue, sedation, OH, anticholinergic s/e
what is the place in therapy of metoclopramide
metoclopramide is a dopamine antagonist that works to prevent acute CINV for low emetogenic regimens, and is useful for breakthrough CINV through
- blockade of dopamine receptors in the chemoreceptor trigger zone
- increase forward gut motility
- stimulation of cholinergic activity in the gut
- antagonism of peripheral serotonin receptors in the intestines
dose
- IV/PO Metoclopramide 10mg OD-TDS
s/e
- mild sedation and diarrhea, EPSE (dystonia, akathisia, parkinsonism, tardive dyskinesia)
ddi
- avoid concom olanzapine due to increased risk of EPSE and neuroleptic malignant syndrome
differentiate between the types of EPSE
dystonia
- involuntary muscle contractions that cause repetitive or twisting movements and abnormal postures
akathisia
- inner restlessness and inability to sit still
parkinsonism
- tremor, rigidity, bradykinesia (slowness of movement), postural instability
tardive dyskinesia
- repetitive involuntary movements especially involving the face, tongue and limbs
what is the place in therapy of benzodiazepines
benzodiazepines can be useful for anticipatory CINV by binding to BZP receptors in the postsynaptic GABA neuron to enhance inhibitory effects of GABA, leading to sedation, reduction in anxiety and possibly depression in vomiting centre
dose
- PO Alprazolam 0.5-1mg
- PO Lorazepam 0.5-2mg
s/e
- dizziness, drowsiness, hypotension, anterograde amnesia, paradoxical reactions (hyperactive, aggressive)
caution
- elderly (risk of falls)
what are the place in therapy of adjunctive agents and what are these adjunctive agents
adjunctive agents are not efficacious enough to be used as upfront antiemetic for acute or delayed CINV, and may be considered for refractory CINV
agents include haloperidol, prochlorperazine, chlorpromazine, promethazine
haloperidol belongs to the class of butyrophenones while prochlorperazine, chlorpromazine, promethazine belongs to the class of phenothiazines
all agents work to block dopamine receptors in the chemoreceptor trigger zones
dose of haloperidol
- IV/PO 0.5-2mg q4-6hrs
s/e of haloperidol
- sedation, EPSE
dose of prochlorperazine
- PO 10mg TDS/QDS
s/e of prochlorperazine
- drowsiness, hypotension, EPSE
what are the guiding principles for breakthrough CINV
- general principle is an additional agent of a different drug class is given
- choice should be based on assessment of current prevention strategies used
- consider the use of several agents of different mechanisms if necessary
- if ongoing vomiting and cannot use PO, use IV
- hydration and fluid repletion for losses
- reassess for next cycle’s antiemetics to ensure it is appropriate
what are the non-pharmacological management strategies for CINV
- take small frequent meals and avoid heavy meals
- avoid foods that are greasy, spicy, very sweet or salty, and foods with strong flavors or smells
- sip small amounts of fluid frequently instead of trying to drink a full glass at one time
- avoid caffeinated beveragges
- avoid lying flat for at least 2 hrs after eating
what does a multiday regimen refer to, consider the treatment regimen of 3-day Carboplatin AUC 3 + Etoposide
- guideline suggests giving appropriate prophylactic therapy for the expected emetogenecity on the day of the chemotherapy administration
- continue delayed prophylaxis alone for 2-3d after completion of chemotherapy if indicated
for 3-day Carboplatin AUC3 + Etoposide
- on d1, Carboplatin AUC3 + Etoposide given –> emetogenicity risk is low to moderate –> cover for acute CINV
- on d2 and d3, only Etoposide given –> emetogenicity risk is low –> cover for delayed CINV only as will cover for acute CINV for low risk of emetogenicity
what is the management strategy for anticipatory CINV
- prevention is key, use optimal antiemetic therapy during every cycle
- behavioral therapy (relaxation/ systematic desensitization, hypnosis/ guided therapy, music therapy)
- acupuncture, acupressure
- consider use of BZP before treatment
what are the consequences resulting from CID
- abnormal electrolytes, inappropriate fluid imbalance, malnutrition, renal failure, weight loss, fatigue and dehydration
- often contributes to delays in therapy, dosage reduction and cessation of therapy
what are the potential causative agents of CID
- cisplatin/ oxaliplatin
- cyclophosphamide
- cytarabine
- 5-FU/ capecitabine
- gemcitabine
- MTX
- doxorubicin/ daunorubicin
- irinotecan/ topotecan
- taxanes
- oral targeted therapy
what is targeted therapy and examples of targeted therapy in cancer treatment
targeted therapies are those that specifically target molecules or pathways involved in the growth and survival of cancer cells while sparing normal cells thus potentially leading to fewer s/e compared to traditional chemotherapy
examples of targeted therapy are tyrosine kinase inhibitors and EGFR inhibitors
how do tyrosine kinase inhibitors work
- inhibit the activity of tyrosine kinase, enzymes involved in the regulation of cell growth, proliferation and survival
- TKI interfere with the signalling pathways that are often dysregulated in cancer cells
how do EGFR inhibitors work
- EGFR inhibitors specifically target the epidermal growth factor receptor, a cell surface receptor that plays a roll in cell growth and division
- EGFR is often overexpressed or mutated in certain types of cancer
- EGFR inhibitors block activation of EGFR thereby inhibiting downstream signalling pathways involved in cancer cell proliferation and survival
what are the risk factors of CID
- age >65yo
- female
- eastern cooperative oncology group (ECOG) performance status ≥2
- bowel inflammation and malabsorption
- bowel malignancy
- biliary obstruction
what is ECOG
eastern cooperative oncology group (ECOG) measures functional status and overall wellbeing with higher scores indicating worse functional status
patients with ECOG ≥2 may have reduced physical functioning and may be less able to tolerate s/e of chemotherapy and may also have underlying health issues that predispose them to GI complications
what are the predictive factors of CID
- first cycle (body has yet to adapt to the effects)
- cycle duration >3w (cumulative effect of the drugs in the GIT)
- concomitant neutropenia (low neutrophil count, a WBC, thus increasing susceptibility to infections like GI infections which can contribute to diarrhea)
- other symptoms like mucositis, anorexia, vomiting, anemia
what is CID caused by
CID is caused by inflamm of the intestinal mucosa, leading to an imbalance between absorption and secretion
how is CID severity graded
CTCAE v5.0 grading
grade 1
- increase of <4 stools per day above baseline
grade 2
- increase of 4-6 stools per day above baseline
- limiting ADL
grade 3
- increase of ≥7 stool per day above baseline
- requires hospitalization
- limiting self-care
grade 4
- life threatening
- urgent intervention needed
grade 5
- death
differentiate between the types of CID
complicated vs uncomplicated
uncomplicated
- CTCAE grade 1 or 2
- no complicating s/sx
complicated
- CTCAE grade 3 or 4
- CTCAE grade 1 or 2 with at least one of the following (fever, cramping, sepsis, frank bleeding, dehydration, neutropenia, decreased performance status, CTCAE >grade 2 for nausea and vomiting)
CTCAE grade 2 for N/V
- moderate nausea
- interfere with usual activites
- decreased PO intake w/o weight loss
- 2-5 episodes of nausea within 24hrs period
what are the goals of therapy for CID
- reduce morbidity and mortality from CID
- improve QoL and ADL
- decrease hospitalization
- improve recovery and intestinal mucosa
what is the general management strateiges for CID
uncomplicated
- diet modification
- oral hydration
- loperamide
complicated
- admit to hospital
- octreotide
what is the treatment algorithm for CID
for uncomplicated CID,
1. withdraw chemotherapy –> resume when symptom resolve and consider resuming at lower dose
2. diet modification and oral hydration
- 8-10 large glasses of clear fluid (electrolyte containing fluids are ideal)
- BRAT diet comprising of easily digestible foods that can help firm up stool
- low-fiber foods like white bread, white rice, pasta, well-cooked vegetables, peeled and cooked fruits, lean protein sources
- avoid trigger foods like greasy, spicy and fried foods, dairy products, caffeine, alcohol, high-sugar foods and drinks, and dietary supplements of high osmolality
- small frequent meals
- probiotic rich foods like yogurt and fermented vegetables to restore balance of beneficial bacteria in the gut and improve digestion
3. loperamide
- PO Loperamide 4mg f/b PO 2mg q4hrs or after every loose stool, continue until 12hrs free of diarrhea then stop (max 16mg/day)
4. monitor for improvement or progression
- if diarrhea persists 12-24hrs, schedule for more intensive PO Loperamide 2mg q2hrs
- if diarrhea progresses to severe/ complicated, treat as per
- if diarrhea persists as uncomplicated 12-24hrs after scheduled Loperamide, add Octreotide or any second agent
for complicated diarrhea,
1. withdraw chemotherapy –> resume when all symptoms resolve, restart at decreased dose
2. Octreotide
- SQ Octreotide 150mcg TDS or IV, dose escalation of 50mcg increments up to 500mcg TDS
3. IV fluid hydration
4. IV abx (eg. Ciprofloxacin x7d)
what is the place in therapy of loperamide
loperamide
- works as an opioid to inhibit smooth muscle contraction of the intestines, decreasing motility
- s/e include constipation, dry mouth, abdominal cramp, drowsiness, dizziness, bloating, rash, N/V
- also paralytic ileus associated at higher doses (refer to temporary paralysis of the muscles in the intestine which disrupts the normal movement of food, fluid and air through the digestive tract)
- shown effectiveness in reduction of fecal incontinence, frequency of bowel movement and stool weight (greater efficacy than Diphenoxylate but limited efficacy for grade 3-4 severity)
what is the place in therapy for octreotide
octreotide
- works to decrease hormone secretion which increases transit time within the intestines, decreases fluid secretion and increases absorption of fluid and electrolytes
- s/e include bradycardia, arrhythmia, constipation, abdominal cramp, N/V, dizziness, HA, enlarged thyroid
- found to be beneficial for 5-FU and irinotecan-induced CID
what are the non pharmacological management strategies for CID
- probiotics containing lactobacillus suggested to prevent chemotherapy or radiation induced diarrhea
- avoid trigger foods like spicy, greasy and fried foods, dairy products, high-sugar food and drinks, caffeine, alcohol, dietary supplements with high osmolality
- avoid high fiber foods
- drink 3L of clear fluids (electrolyte containing fluids are ideal)
- small frequent meals
- BRAT diet containing easily digestible foods to firm up stool
why is irinotecan associated with causing diarrhea
irinotecan is a selective reversible inhibitor of acetylcholinesterase leading to cholinergic response whereby there is increased intestinal motility and secretion
what are the types of irinotecan-induced diarrhea and management strategies
early onset (within 24hrs from administration)
- dose dependent
- most become symptomatic during infusion, with mean symptom duration being 30mins
- treat with atropine SQ/IV 0.25-1mg (max 1.2mg) which works to inhibit ACh at muscarinic receptor by acting as a competitive antagonist, causing s/e like blurred vision, constipation, dry mouth, dizziness, insomnia, tachycardia (note c/i in glaucoma)
late onset (after 24hrs from irinotecan)
- can occur at any dose and frequency
- median onset with q3w dosing is 6d vs median onset with q1w dosing is 11d
- treat with loperamide 4mg on first loose stool f/b 2mg q2hrs or 4mg q4hrs at night, until 12hrs free from loose stools
what are the factors that increase risk of developing constipation
- lowered fluid intake or dehydration
- lack of fiber or bulk-forming food in the diet
- low physical activity/ alot of bed rest
- vitamins or mineral supplements like iron and calcium pills
- high serum levels of calcium and phosphate
- thyroid disorder
- depression
- overuse of laxatives
- cancer growing in large intestine or pressing on spinal cord
- medications (pain medications esp opioids like codeine and morphine, chemotherapy agents like vinca alkaloids eg. vincristine/ vinblastine/ vinorelbine, anti-nausea medications like ondansetron/ granisetron/ ASM)
what are the symptoms of constipation
- cramping or pain
- belching
- gas or flatulence
- bloating or feeling of fullness
- loss of appetite
- swollen or distended abdomen
- small hard stools that are hard to pass
- leakage of small amounts of stools that resemble diarrhea
- straining for a bowel movement
- no regular bowel movement for ≥2d
- N/V
- rectal pressure
how can constipation be prevented
- increase fibre intake to add more bulk to stool (but note colorectal cancer pts who underwent surgery and are experiencing constipation may have restrictions on fibre intake)
- increase intake of natural laxatives (vegetables, caffeine, prunes; but prunes are very sweet)
- increase physical activity
- ensure sufficient caloric intake
what are the management strategies for constipation
- stool softeners (dosucate sodium/ calcium)
- help the stool to hold water and keep it soft
- sometimes used together with a laxative - laxatives
- produce or stimulate bowel activity (lactulose, senna, mineral oil, bisacodyl)
- increase fibre or product bulk (psyllium)
- suppository form that promotes bowel activity (glycerine, bisacodyl) - enemas (phosphate enema aka fleet, tap water)
- to clean out the bowel or deliver laxatives by introducing liquid to soften stool, lubricate and stimulate muscles for expulsion of stool
- can also help to relieve severe constipation or fecal impaction
what are the typical dosing of various laxatives
duphalac 10mL TDS
senna 15mg ON
bisacodyl 5mg ON
fybogel 1 sachet BD
what is mucositis
damage to the mucosa of the oral cavity, pharynx, larynx, esophagus and GI tract due to cancer therapy
what is the pathophysiology of mucositis
- chemotherapy and radiation causes direct damage to epithelial stem cells, tissue response varies by seasonal and circadian changes, targeted therapies and small molecule inhibitors have demonstrated the ability to cause a variety of GI toxicities, incl mucositis
- epidermal growth factor plays a role in maintaining mucosal integrity by regulating growth and repair of epithelial tissues, EGFR can be found in the esophagus and levels are increased in an inflamed mucosa (in an attempt to repair damaged tissue by upregulating cell proliferation, survival and differentiation, but this upregulation of EGFR can cause increased sensitivity, enhance inflamm response, delay healing, and altered cell differentiation)
what are the stages of mucositis
- initiation
- chemotherapy and radiation causes direct toxicity
- via generation of oxidative stress and ROS
- increased vascular permeability leads to local accumulation of toxic drugs - upregulation
- ROS damages DNA, leading to epithelial cell death (extent of tissue damage dependent on rate of oral epithelial proliferation)
- nuclear factor KB activation leads to gene upregulation leading to production of pro-inflammatory cytokines and expression of adhesion molecules –> tissue damage, activation of COX2, angiogenesis and apoptosis - signaling and amplification
- pro-inflammatory cytokines (TNFalpha, IL1beta, IL6) are released
- positive feedback, indirectly increasing and extending toxicity to mucosa - ulceration
- prior injury to basal epithelial cells causes atrophy and mucosa breakdown
- oxidative stress increases inflammatory infiltrates
- macrophages are further activated by colonizing bacteria which increases release of pro-inflammatory cytokines - healing
- WBC recovery at d12-16
- proliferation of epithelial cells as chemotherapy gets cleared by liver and kidney
- return of flora
- continuous angiogenesis (formation of new blood vessels from current vasculature) increases risk of future mucositis