Attendees at my last big lecture…

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Transcript Attendees at my last big lecture…

Hospice and Palliative Care Lecture
Grand Rapids, MI 04 26 2012
Radiation Oncology in
Palliative Care
David D. Howell, M.D. FACR FAAHPM
University of Michigan Medical School
Department of Radiation Oncology
Ann Arbor, MI
Please note that this presentation is for educational purposes
only. Information contained within is subject to change with the
advent of new literature and technology.
© Precision Oncology PC.
Disclosure Information
David Howell
Has no relevant financial relationships to disclose.
Description
During this review, the participant can expect to learn
– The basics of radiation as it is used in cancer
treatment.
– The radiation oncologist’s process through
consultation, treatment recommendations, and actual
treatment.
– Situations where radiation might be used to provide
palliation.
– Strategies on how to effectively communicate with
your consulting oncologists on goals of care in
hospice and palliative care situations.
The couple in for consultation…
A man came to see me for a
prostate problem.
After I had interviewed him, I asked
to examine him.
As he was shimmying his pants
down his legs, the lady who
accompanied him said…
The couple?
“I’m just the
neighbor--I’d better
leave!!!”
I don’t make assumptions
anymore.
Fresh Hope on Cancer…
This magazine was from the 1950s.
…
ARE WE MUCH FURTHER AHEAD TODAY???
Atom Smasher
Radiation Oncology
is a Palliative Care Specialty
Most radiation is for palliation
– Glioblastoma multiforme
– Stage III Lung Cancer
– Pancreatic Cancer
– Esophageal Cancer
– Gastric Cancer
– Stage IV low grade Non Hodgkin Lymphoma
– All Stage IV patients with metastatic disease
The Radiation Oncologist’s Tool
The Linear Accelerator
Part 1
Radiation Fundamentals
RADIATION TYPES
used in therapeutic applications.
Photons
Electrons
Protons
How Radiation does NOT work..
Burn
Fry
Cook
Zap
Microwave
Nuke
Radiation Effects
Direct Effect – Photon directly
impacts on DNA
Indirect Effect– Photon impacts
upon H2O, which creates free
radicals, which impact on DNA
Leads to DNA strand breaks
Direct and Indirect Effects
DNA Strand Breaks and Repair
A. Normal tissues have better repair
mechanisms.
B. Cancer cells have poorer repair
mechanisms.
C. Fractionation – allows normal tissue to
repair while treatment continues to work
to irreparably damage malignant cells.
D. Cancer cells die a reproductive death
during cell division due to incomplete
DNA for mitosis.
Acronyms (and Initialisms)
Defined
TLA: Three letter acronym.
FLA: Four letter acronym.
FLA is also a TLA.
Measurement of dose definition
Daily treatment fractions, prescribed in Gy
Gy (pronounced “gray”)
Gy defined is a unit of radiation
absorbed dose.
Named after a British physicist
Formerly known as rads (100 rads
equals 1 Gy)
Fractionation Examples
Standard Fractionation
– Once a day treatments
– Dose 1.8 to 2.5 Gy
Hyperfractionation
– Twice a day treatment
– Dose 1.0 to 1.6 Gy per treatment
Hypofractionation
– Once a day treatment
– Higher dose per treatment (3.0 to 10 Gy per
treatment)
Radiation Dosing Paradigm
Sigmoid curves of tumor effect and
complications define the
therapeutic index, or ratio
The therapeutic index is the comparison
of the amount of a therapeutic agent
(radiation) that causes the therapeutic
effect to the amount that causes death or
significant morbidity.
Different for each tissue, tumor, modality.
Therapeutic Index
Radiation Fractionation Rationale
A. Small dose per day leads to
A. Better chance for normal tissue repair.
B. Reduced toxicity.
C. Longer treatment course.
D. Efficacy curve moves to right, complication curve to
right.
B. High dose per day leads to
A. Greater normal tissue side effects.
B. Increased risk of late toxicity.
C. Shorter treatment course.
D. Efficacy curve moves to left, complication curve to left.
Radiation Toxicity
Radiation affects more rapidly dividing cells
with greater intensity.
Examples of rapidly dividing cells and effect:
A. Hair follicles —regional alopecia where beam is
aimed.
B. Bone marrow —lower levels of circulating blood
cells
C. GI mucosal cells—mucositis where beam is
aimed.
Effect on other normal tissues:
Late Effects on Normal Tissue
from Rosen E.M. et. al. Biological Basis of Radiation Sensitivity Oncology 14(4) 2000
Part Two
Planning and delivering
radiation
Radiation Processes - Consultation
Decision is made that there may be a role for
consultation.
A. Pre-consultation call – call radiation oncologist
with brief presentation of patient’s situation, to
determine if consultation is worthwhile (or just write).
B. Decide prior to consultation whether visit is for
evaluation alone or evaluation and management
with or without call to referring physician.
C. Do you view radiation oncologist as an integral part
of treatment team to assist with decision making, or
as a technician to provide service and procedures?
D. If decision for treatment is affirmative then -
Radiation Processes - Simulation
Process by which planning is initiated to
determine how to give treatment.
Requires patient to undergo imaging either
with CT imaging or fluoroscopy based x-ray
simulator.
Patient placed in position on flat tabletop that
can be reproduced on a daily (or one time)
basis.
Devices for immobilization, localization, and
patient comfort are used, e.g. vac-loc bag,
headrest, other immobilization devices.
Images are generated to be used for next step
– dosimetry.
Time for simulation: 30-60 minutes.
Immobilization Devices
Face Mask
Breast Board
Radiation Simulator
Classic-fluoroscopic unit with image
intensifier
– Create 2D images
Contemporary- Dedicated CT scanner
with flat table top which can reproduce the
table top of the linear accelerator.
– Create 3D images
Radiation Simulator-CT Scan
Radiation Processes - Dosimetry
Process by which images are used with
software package to decide optimal
treatment plan.
Contouring of volumes, set fields on
software/computer imaging.
Beam dimensions
–
length by width
Beam orientation
–
–
0-359 degrees
Table pitch and yaw
Beam Modifiers
Poured blocks Multileaf
collimator
Radiation Processes
Verification Simulation
Confirmation of planned fields on actual
linear accelerator (treatment machine).
Medical physics check of machine,
all calculations, beam energy.
Treatment.
Radiation Treatment-Linear Accelerator
Parts:
Table
Gantry
Collimator
Radiation Treatment-Linear Accelerator
Beam orientation, collimator beam shaping
The Radiation Oncologist’s Tool
The Linear Accelerator
Radiation Treatment-Linear Accelerator
Treatments
– Painless and quick.
– Take 10 to 30 minutes of time on the machine,
depending on number of treatment fields and
complexity.
– Much time is spent in properly positioning the
patient to reproduce what was planned.
– Patient usually lies flat on table.
– Gantry and collimator move about the patient.
– Patient may hear buzzing noise of machine as it is
on.
Part 3
Radiation in Palliative Care
Core Competency
Curative Radiation Therapy
Five days per week, over six to eight
weeks
Cumulative side effects
Treat: Tumor and risk areas
Goal is eradication of all tumor cells
Concerns about acute and late side
effects
Palliative Radiation Therapy
Hypofractionation
One day to two weeks.
Treat: Only site requiring palliation.
– Forego areas at risk for subclinical or
asymptomatic cancer.
– May purposely miss known areas of tumor.
Goal is relief of symptoms.
Less concern about long term side
effects.
Radiation Therapy Side Effects
Acute
– Mild, cumulative, self-limiting, common
– Related to total dose more than dose per
fraction
– Usually relate to region treated
Late
– Months to years later, more severe, rare
– Depends heavily upon dose per fraction
Palliative Radiation Therapy
Fractionation Conundrum
Goal #1
–Provide rapid palliation.
Goal #2
–Minimize side effects.
Palliative Radiation Therapy
Clinical Situations
Palliative Radiation Therapy
Indications
Pain
Bleeding
Obstruction
Pressure
Prophylactic
Palliative Radiation- Bone Metastases 1
Factors to Consider in Treatment
Radiographic appearance:
Osteolytic, osteoblastic, mixed.
Location:
Weightbearing area (e.g. femur), Nonweightbearing (rib).
Actual fracture, impending fracture, or no
fracture.
Palliative Radiation- Bone Metastases 3
Factors for Consideration
Vertebral bone involvement
Spinal canal impingement
Spinal canal compression
Thecal sac impingement
Vertebral bone alone without impingement.
THESE ARE DIFFERENT PROBLEMS, may need
different solutions
– More radiosensitive histologies
breast, prostate, myeloma, lymphoma.
– Less radiosensitive histologies –
lung, kidney, melanoma.
Palliative Radiation- Bone Metastases 5
Dose-Fractionation
Sample fractionation schema
– 8 Gy in a single fraction
– 20 Gy in five fractions
– 24 Gy in six fractions
– 30 Gy in ten fractions
One treatment up to ten treatments
Some physicians will prescribe more!
Palliative Radiation- Bone Metastases 7
Treatment With Radiotherapy
Time until relief
– Highly variable: Improvement in
2,3,or 7-14 days, sometimes takes
weeks to complete response
–Maximize analgesics
– Remember NSAIDs
–Taper pain meds when one can.
Palliative Radiation- Bone Metastases 8
Treatment With Radiotherapy
In the vast majority of patients with
uncomplicated painful bony metastases, a
single 8 Gy fraction of radiation will provide
equivalent:
A. Pain relief
B. Need for narcotics
C. Time to relief as
Equivalent to a multifraction course
of radiation.
Palliative Radiation- Bone Metastases 9
Single vs. Multiple Fractions
Reasons Radiation Oncologists May Prefer
Multi-Fraction Courses of Radiation-1:
A. Postop patients (orthopedic or neurosurgical
procedure).
B. Impending fracture.
C. Prior radiation treatments to same area.
D. Spinal cord/canal compression.
E. Soft tissue component to metastases.
Palliative Radiation-Bone Metastases 10
Single vs. Multiple Fractions
Reasons Radiation Oncologists May Prefer
Multi-Fraction Courses of Radiation-2:
A. Re-treatment rates higher with single fraction
(2/11 patients will need retreatment vs. 1/11
patients treated with multiple fractions).
B. Concern for increased toxicity with single
fraction radiation (however studies have shown
less GI toxicity with single fraction radiation
and no significant late CNS toxicity with single
fraction radiation).
C. Treating physician comfort level.
Palliative Radiation-Bone Metastases 11
“Costs” of ANY Treatment
Financial
– Cost of treatment (insurance, copays, etc.)
– Associated costs of travel, time away from work, other
Time (opportunity costs)—I’d rather be…
– For patient
– For caregiver, transporter
– Travel to center for therapy
Side effects
False hope
Cost of Radiation
SFRT (single fraction radiation therapy):
– With simple to intermediate level of complexity,
should be ~$1200-1700.
– Less than the costs of the ambulance rides to and
from the hospital
If one uses SRS (stereotactic radiation), or
Cyberknife® radiation techniques, and multiple
fractions, costs can go up. Generally no need to
use these techniques for palliative treatment of
bone metastases.
IMRT
IMRT-intensity modulated radiation
therapy
– Use specialized treatment planning
techniques for more sophisticated beam
configurations.
– May be helpful to reduce toxicity in some
clinical situations, e.g. certain H&N
malignancies, some prostate cancers.
– Rarely indicated in the palliative setting
– $$$ compared to conventional planning
techniques and treatment delivery.
Palliative Radiation-Bone Metastases 12
Patient and Caregiver Factors:
1 fraction of radiation vs. 10 fractions of
radiation – Differences:
A. Nine less visits to radiation oncology facility
for patient/caregiver with single fraction
treatment.
B. Single fraction is ~1/3 – 1/2 the (technical and
professional) cost of multi-fraction radiation
therapy
(Why? – the expense
associated with radiation treatment planning
is significant component of overall total cost).
Palliative Radiation
Obstruction
Airway obstruction-dyspnea.
Visceral obstruction-pain.
Bladder outlet obstructiondysuria.
Esophagus obstructiondysphagia.
Palliative Radiation
Pressure
Brain metastases.
Hepatic metastases.
Splenomegaly.
Palliative Radiation
Bleeding
Radiation effective in suppressing bleeding from:
A.
B.
C.
D.
E.
F.
Oral cavity/oropharynx.
Tracheal-bronchial tree.
Bladder.
Gynecologic regions – uterine, cervix, vagina, vulva.
GI – rectum, anus.
Dermal-cutaneous.
Single fraction vs. multiple fraction radiation.
Regimens used – 8 to 10 Gy in 1 fraction; 3.7 Gy b.i.d.
x 2 days (4 Rx total), repeated every 2-3 weeks or until
relief;
8 Gy each week x3 weeks or until relief, 30
Gy in ten fractions.
Palliative Radiation– Lung Cancer
Radiation therapy can be effective in
relieving symptoms from advanced lung
cancer:
A.
B.
C.
D.
E.
Dyspnea.
Hemoptysis.
Refractory cough.
Pain.
Superior venal caval compression.
Palliative Radiation - Dyspnea
Dyspnea= Shortness of Breath
Occurs in 60-80% of patients with lung cancer.
Is it underlying lung disease or tumor
obstruction?
Palliation of bronchial obstruction-options
–
–
–
–
–
External beam radiotherapy
Chemotherapy
Laser treatment of endobronchial lesions
Stents placed to widen a narrowed bronchus
Brachytherapy-temporary radiation implants to
provide localized radiation to endobronchial
lesions.
Esophageal Cancer and Dysphagia
Options for treatment
– Radiation Therapy
– Esophageal stents
– Endoscopic dilation
– Laser
– Photodynamic therapy
Symptomatic Splenomegaly
Signs and Symptoms
Presenting symptoms
– Usually in the presence of known hematologic
malignancy, myelodysplasia, lymphomas and chronic
leukemia
– Abdominal pressure sensation
– Impact on adjacent organs (stomach, bowel)
– Inability to bend at the waist
Signs
– Palpation of spleen to midline or into pelvis
– Labs show platelet and red cell consumption
Symptomatic Splenomegaly
Treatment
Surgery, if performance status allows
Radiation Therapy
– Tumor cells in spleen are very sensitive to
radiation.
– Very low doses, 0.5 Gy/fraction (1/4 normal)
given 2X/week
– May note relief after only 1.5 to 3 Gy, 3 to 6
treatments total.
– Need to monitor CBC counts, watch for tumor
lysis, check spleen size frequently.
– Treat to sufficient level of relief, then stop.
– May repeat treatment course, if necessary.
Spinal Cord/Canal Impingement/Compression 1
Symptoms
– First sign: Localized Pain most common
(10% cervical, 70% thoracic, 20% lumbar)
–
–
–
–
Decreased ambulation
Traumatic fall
Urinary or fecal incontinence
May present as first manifestation of neoplasm, in
which biopsy is indicated
–NEED TO ACT FAST !!!!!!!
Spinal Cord/Canal Compression 2
Presentation
Physical signs -more
progressive involvement:
– Focal weakness
– Decreased sensation to
pinprick
– Altered reflexes
Imaging findings
– MRI is gold standard
– Look for evidence of
intrinsic (intramedullary),
extrinsic (extramedullary)
disease, multiple levels.
Spinal Cord/Canal Compression 3
Treatment
Early recognition is key!!
– Steroids (e.g. dexamethasone) decrease swelling,
maintain function
– If ambulatory, 80% retain capability
– If paraparetic, 40% will regain ability to walk
– Chances for success drop with each passing day
patient has symptoms
– Chemotherapy can be used for chemosensitive
diseases such as myeloma or lymphoma WITH
CAUTION.
Spinal Cord/Canal Compression 5
Role of Dexamethasone
Dexamethasone may be effective in suppressing
symptoms of increased pressure associated with
spinal canal/ cord/ thecal sac impingement or
compression
– (and brain metastases)
– Dexamethasone can be initiated if symptoms of
increased spinal canal/cored impingement are
present.
– In asymptomatic spinal canal/vertebral bone
metastases, dexamethasone should not be
administered initially, reserve for symptoms.
– Initial dose recommended is 12-24 mg in daily divided
doses.
Spinal Cord/Canal Compression 6
Role of Dexamethasone
Biologic T ½ is longer than pharmacologic
T½.
– As a result, every 6-hour delivery not
necessary.
– T.I. D. treatment (upon awakening,
lunchtime, and afternoon) may reduce risk of
insomnia associated with p.m. administration
of dexamethasone. Can go to B.I.D as well.
Spinal Cord/Canal Compression 7
Role of Dexamethasone
Patients should be monitored with periodic
neuro checks to assess status, especially early
on.
Advise patient and caregiver on potential
acute and late effects of dexamethasone
– Early- insomnia, increased appetite, mania,
GI reflux, hip extensor weakness
– Late—muscle weakness, acne, facial
swelling, buffalo hump, endocrine disorders
Spinal Cord/Canal Compression 8
Role of Dexamethasone
Once symptoms are controlled, dexamethasone
taper should be instituted with careful monitoring
of patient symptoms.
– 33% reduction in dose every 3 days until
stopped.
– Have pt and caregiver watch for new or
reemergence of symptoms such as nausea,
vomiting, diplopia, headache) which could
indicate increase in pressure again.
Spinal Cord/Canal Impingement/Compression 9
Surgical intervention (stabilization, not
laminectomy) should be considered in patients with:
Longer life expectancies (e.g. some breast,
prostate patients)
B. Good prognosis patient with retropulsed
bone fragments into spinal canal or other
mechanical abnormalities, e.g. crush.
C. Consider patient’s pre-treatment neuro
status –
ability to ambulate, sensory
abnormalities, other findings.
A.
Spinal Cord/Canal Impingement/Compression 10
Time in care:
remember it is not just the surgery, but also
need to consider the time for physical
rehabilitation — both inpatient and outpatient
—less for cervical, more for thoracic and lumbar
surgeries, can be weeks.
Important to have honest input from all on the
process, especially to establish good
prognostication prior to embarking on what
may be a lengthy treatment and recovery.
Spinal Cord/Canal Impingement/Compression 14
Radiation therapy can be used alone with good
relief and comparable chances of recovery.
Radiation therapy dose-fractionation schedules
– 8-10 Gy/single fraction
– 20-30 Gy/5-10 fractions (standard, safe)
– 50 Gy/25 fractions (solitary plasmacytoma or
lymphoma)
Treatment of Brain Metastasis 1
Steroids
– Dexamethasone.
Lower mineralocorticoid effects than prednisone.
Radiation Therapy
Diuretics
Supportive care
Surgery
Treatment of Brain Metastases 3
Radiotherapy Treatment specifics
Whole brain generally treated
Why not partial brain?--due to risk of other areas of
potential subclincal involvement in other areas
– 30 Gy/10 fractions standard
– Some give 20 Gy/5 fractions
– Some will consider longer course for favorable
prognosis patients
Whole Brain Radiotherapy Results5
On average, extends life from 2 to 4-6
months
Prognostic factors
– Disease control at primary site
– Histology of brain metastasis
“Radioresistant” tumors
– Renal cell or melanoma primaries
– May be better treated by surgery or
radiosurgery
Treatment of Brain Metastases 6
Palliative Radiation – Median Survival
Median survival for patients with brain
metastases impacted upon by many
factors:
A. Karnofsky performance status (KPS)-higher better
B. Size and # of brain metastases-- fewer
better
C. Brain is solitary site of metastatic disease.
D. Disease controlled below foramen magnum-yes
E. Age.
Treatment of Brain Metastases8
Palliative Radiation – Treatment Options
Fractionation Schema
1.8 Gy x 25 in five weeks
2 Gy x 20 in four weeks
3 Gy x 10 in two weeks
4 Gy x 5 in one week
8.5 Gy x 2, 1 week interval between treatments
No difference in response rates among
various treatment schedules, though more
rapid response seen with hypofractionated
schedules.
Conclusions
Radiation Therapy may be a useful tool to
aid for palliation of many advanced
malignant processes.
Work with your radiation oncology
colleagues as consultants and as
therapeutic partners
Identify situations where radiation may be
delivered over a shorter period of time with
equivalent chances for palliation.
Unrealistic Expectations
What are the chances that I will live longer
or better with an intervention?
What did I hear vs. what was it that was
stated?
Clear communication vs. best outcome.
Conclusions
Radiation Therapy may be a useful tool to
aid for palliation of many advanced
malignant processes.
Work with your radiation oncology
colleagues as consultants and as
therapeutic partners
Identify situations where radiation may be
delivered over a shorter period of time with
equivalent chances for palliation.
Contact Information
David Howell MD FACR FAAHPM
contact information:
www.thecancerdoctor.com
www.thepalliativedoctor.com
[email protected]