Transcript Microwave Ablation of an Adrenal Metastasis - IO

Microwave Ablation of
Bilateral Adrenal Metastases
Vincenzo Wong, MD
Louis Hinshaw, MD
University of Wisconsin Madison
History
65 year old male with history of right
nephrectomy for renal cell cancer of
unknown stage presents 2 years later
with new bilateral adrenal lesions
A
B
Axial (A) and coronal (B) noncontrast abdominal CT
demonstrate bilateral adrenal
nodules (arrows). The right
kidney is surgically absent.
C
D
Axial PET/CT images (C & D)
show associated mildly
increased FDG avidity
(arrows) [max SUV of 4.7].
Percutaneous CT guided core biopsy
of the left adrenal lesion confirmed
metastatic disease.
Patient was given the option of
bilateral metastatectomy or thermal
ablation. Patient opted for ablation.
Ablation planning ultrasound demonstrates
a hypoechoic circumscribed left adrenal
mass felt to be better accessible utilizing CT
guidance.
Question
What unique risks would you need to discuss with the patient that
could occur during the procedure and long-term after the
procedure?
Question
What unique risks would you need to discuss with the patient that
could occur during the procedure and long-term after the
procedure?
Answer
Hypertensive crisis can occur during the procedure, and potentially lead
to hemodynamic collapse, organ failure, and death.
After the procedure, adrenal insufficiency may occur depending on how
much adrenal tissue is ablated.
Probe 1 Placement
Probe 2 Placement
During Ablation
Post Ablation
Patient was placed in a prone position. Two 20-cm Certus 140
microwave ablation probes were placed within the left adrenal
mass under fluoroscopic CT guidance via a transpleural approach.
A 5 minute total ablation was performed. Both probes were run at
95 watts for 1 minute and subsequently at 70 watts for 4 minutes.
A trace pneumothorax (arrow)
was noted during the
procedure not requiring a chest
tube.
Pre Ablation
Post Ablation
Post ablation images show
decreased size of the lesion
secondary to tissue contraction
Questions
For microwave ablation, at what point during the
procedure would you most likely expect
hypertensive crisis to occur?
a)
b)
c)
d)
During probe placement?
During probe heating?
During probe cooling?
After probe removal?
Questions
For microwave ablation, at what point during the
procedure would you most likely expect
hypertensive crisis to occur?
a)
b)
c)
d)
During probe placement?
During probe heating?
During probe cooling?
After probe removal?
Hypertensive crisis is most likely to
occur during cell rupture (causing
release of catecholamines).
Most likely to occur during:
Heating for microwave and RF ablation
Thawing for cryoablation
Pre Ablation
Probe Placement
During Ablation
Patient returned two weeks
after treatment of the left-sided
lesion for ablation of the right
adrenal mass (arrow).
A single Certus 140 probe was
placed into the right adrenal
lesion.
Post Ablation
Scout CT image shows the
patient in an ipsilateral
decubitus position. The treated
left adrenal mass (arrow) is
redemonstrated.
A 5 minute microwave ablation
cycle was performed.
Post ablation images did not
show any immediate
complication.
Question
What is the likelihood of long-term adrenal
insufficiency in this patient?
Question
What is the likelihood of long-term adrenal
insufficiency in this patient?
Answer
Likely… as both adrenal glands will have been ablated
Question
How much adrenal tissue would have to be
destroyed before expecting adrenal insufficiency?
a) 30%
b) 50%
c) 70%
d) 90%
Question
How much adrenal tissue would have to be
destroyed before expecting adrenal insufficiency?
a) 30%
b) 50%
c) 70%
d) 90%
A
B
Patient presented approximately 1 year later (A, C, E)
with three new lesions in the right adrenal gland
(arrows). The treated lesion (arrow) is redemonstrated.
Three PR probes (B, D, F) were placed into the three
nodules and a 5 minute ablation cycle at 65 watts was
performed for each lesion.
C
D
E
F
Question
What is the likelihood of hypertensive crisis during
this ablation session?
Question
What is the likelihood of hypertensive crisis during
this ablation session?
Answer
Unlikely, as the adrenal gland has been previously
ablated.
Question
The right adrenal gland may have been initially
undertreated after the first ablation.
If the original metastatic lesion was 3 cm, what diameter
ablation zone would you aim to achieve?
a) 3 cm
b) 4 cm
c) 5 cm
d) 6 cm
Question
The right adrenal gland appeared to be initially
undertreated after the first ablation.
If the original metastatic lesion was 3 cm, what diameter
ablation zone would you aim to achieve?
a) 3 cm
b) 4 cm
c) 5 cm
d) 6 cm
For metastatic disease, 1 cm ablation
margins surrounding the lesion would
be ideal.
1 cm
3 cm
1 cm
5 cm
ablation
zone
Restaging non-contrast CT images show stable appearance of the
ablated adrenal lesions (arrows) without evidence of local or metastatic
disease progression for 3 years.
Patient currently follows regularly with endocrinology for hormone
replacement therapy for cortisol deficiency.
Background
• Adrenal tumors comprise 1% of all neoplasms and are
detected in 4-6% of patients undergoing imaging
• Select patients with isolated metastatic disease to an
adrenal gland reported to have a survival benefit from
adrenalectomy
• Ablation is an effective alternative to adrenalectomy for
non-surgical candidates
Indications
• Potential indicated adrenal lesions include:
– Non functioning and functioning adrenal tumors (cortisol
producing adenomas, aldosteronoma)
– Pheochromocytoma
– Adrenocortical carcinoma
– Metastases (most commonly lung, gastrointestinal tract,
renal cell carcinoma, and melanoma)
• Better results reported for lesions ≤ 5 cm
Pre-ablation Preparation
• CT or MRI for ablation planning
• For suspected functioning tumors
– Serum or urine assays for cortisol, aldosterone, and
catecholamines obtained prior to ablation (to evaluate
for change after treatment)
Pre-ablation Preparation
• Endocrinology consultation
– Necessary in management of functioning adrenal
tumors
– Can assist with pre-treatment blockade with ⍺-blocker
and β-blocker
– Can monitor hormone levels and manage hormone
replacement therapy after ablation
Question
What is a potentially harmful regimen for adrenergic
blockade?
a) β-blocker alone
b) β-blocker + ⍺-blocker
c) ⍺-blocker alone
Question
What is a potentially harmful regimen for adrenergic
blockade?
a) β-blocker alone
b) β-blocker + ⍺-blocker
c) ⍺-blocker alone
β-blockers are not administered
until adequate ⍺ blockade has
been established.
Unopposed ⍺-adrenergic receptor
stimulation can precipitate a
hypertensive crisis.
Pre-ablation Preparation
• Anesthesiology Consultation and Sedation
– Adrenal ablations generally performed under general
anesthesia (to preempt hypertensive crisis and prepare
for treatment should one occur)
– Brief anesthesiology team about risk of hypertensive
crisis to facilitate rapid administration of antihypertensive medications during procedure
Outcomes
• Functioning adenomas
– Similar outcomes between ablation modalities
– 75-100% success rate after single ablation
– 100% success after second ablation
• Malignant Tumors
– Thermal ablation rates of residual or recurrent
disease as low as 0 to 25%.
– Chemical ablation appears less efficacious for
controlling adrenal metastases
Complications
• Hypertensive Crisis (HC)
– Due to release of catecholamines from manipulation of the normal
non-tumorous adrenal gland
– No difference in risk between ablation modalities
– Generally occurs during heating for microwave and RF ablation, and
thawing for cryoablation
– Adrenergic blockade reported to decrease peak SBP in HC, although
may not actually decrease risk for developing HC
Greater risk of HC
• tumor diameter < 4.5 cm
• visualization of normal
adrenal tissue
Lower risk of HC
• tumor diameter > 4.5 cm
• gland replaced by tumor
• previously ablated or irradiated
gland
Complications
• Tips in mitigating hypertensive crisis
–
–
–
–
Pre-ablation adrenergic blockade
General anesthesia favored over moderate sedation
Invasive arterial blood pressure monitoring favored
During ablation, short acting anti-hypertensive agents favored over
long-acting agents (risk of hypotension with long acting agents
when catecholamine surge ends)
– Warn anesthesiology team prior to tissue heating (microwave &
RFA) and prior to thawing (cryoablation)
– Brief anesthesiology team about need for rapid administration of
anti-hypertensive medications
Complications
• Adrenal Insufficiency
– Exceedingly rare
– Reported that >90% of adrenal tissue must be destroyed to
compromise biochemical adrenal function
– Managed by hormone replacement therapy
•
•
•
•
Pneumothorax
Infection
Bleeding
Pain
Conclusions
• Ablation offers effective short-term local control of
primary and metastatic adrenal neoplasms
• Unique risks include hypertensive crisis (common) and
adrenal insufficiency (rare)
• Multidisciplinary approach with endocrinology and
anesthesiology important to safe and successful ablation
• Aim for 1 cm ablation margins for metastatic lesions
References
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Uppot, R. N. and D. A. Gervais (2013). "Imaging-guided adrenal tumor
ablation." AJR Am J Roentgenol 200(6): 1226-1233
Fintelmann, F. J., et al. (2015). "Catecholamine Surge during ImageGuided Ablation of Adrenal Gland Metastases: Predictors, Consequences,
and Recommendations for Management." J Vasc Interv Radiol.
Yamakado, K. (2014). "Image-guided ablation of adrenal lesions." Semin
Intervent Radiol 31(2): 149-156
Welch, B. T., et al. (2011). "Percutaneous image-guided adrenal
cryoablation: procedural considerations and technical success." Radiology
258(1): 301-307