UAE: Does the choice of embolic matter

1
UAE Does the choice of embolic matter?

• John C. Lipman, MD, FSIR
• Atlanta Interventional Institute
• Marietta, Georgia

2
In Conclusion

• Yes

3
Why does embolic choice matter?

• Successful long-term outcome is defined by
• Symptom control
• No recurrent growth of fibroids.
• Imaging documentation by contrast-enhanced MRI.
• Absence of re-interventions
• Fibroids need to completely infarct to avoid
  recurrence.
• Technical goal of UAE is to infarct all the
  fibroids.

4
Causes For UAE Failure

• 1. Technique issues
• 2. Collateral supply
• 3. Choice of embolic

5
Perfusion of fibroids after UAE predictor of
outcome

• DeSouza (Rad 2002 (2) 222 367-74) perfusion of
  myometrium dominant fibroids pre post UAE
  (1mo/4mo).
• Pelage (SIR 05 abstract)
• -79 women with MRI _at_ 24, 6m,12m, 24m.
• -Those completely infarcted _at_ 24 stayed
  infarcted.
• -This group had significant clinical improvement
  vs. incompletely infarcted group.
• -No difference in uterine dominant volume
  reduction between groups.

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No Symptom Recurrence Complete Fibroid Infarction
3 Months
1 Year
2 Years
3 years
Baseline
7
Early Recurrence Incomplete Fibroid
InfarctionRecurrent symptoms at 2.5 years
post-embolization (Radiology 2004230803-9).
Pre
3 mo
1 year
2 years
3 years
4 years
8
Late RecurrenceOld and New Fibroids
46 months
26 Months
4 Months
Baseline
9
Currently materials in use in United States and
Europe

• Particle PVA (Contour, other brands)
• Tris-acryl Gelatin Microspheres (Embospheres)
• Tris-acryl Gelatin Microspheres AU (Embogold)
• Spherical PVA (Contour SE)
• Spherical PVA hydrogel (Bead Block)
• Gelatin sponge (Gelfoam)

10
Particle PVA (Contour, others)

• Longest use of any product.
• Relatively inexpensive.
• Hard to inject, can easily clog microcatheters.
• Initial experience in UAE all based on particle
  PVA.
• Early suspicions that PVA caused more pain than
  necessary.

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Embosphere Microspheres

• First embolic to win FDA clearance specifically
  for uterine embolization.
• Easy to inject.
• Demonstrated effective in randomized comparison
  to particle PVA.
• More expensive than particle PVA.
• Allows easier control over endpoint (more gradual
  occlusion).
• Believed to cause less pain than PVA (anecdotal).
  Papers by Ryu, Spies showed no difference.

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Imaging Outcome after TAGM

• Banovac (Spies) JVIR 02 13 681-7.
• -61 fibroids, 23 pts.
• -Pre 3-4 month post MRI.
• -54/61 (89) 21/23 dominant (91) were
  completely devascularized.

13
PVA Particles vs Embospheres

• Randomized comparison study of embolics.
• 100 subjects (54 TAGM, 46 PVA)
• Outcome measures
• Short-term pain (VAS scale), recovery
• Symptom, quality of life change 3 months
• Imaging outcome at 3 months.

Spies JB, et al. Polyvinyl Alcohol Particles and
Tris-acryl gelatin Microspheres for Uterine
Artery Embolization for LeiomyomasResults of a
Randomized Comparative Study. J Vasc Intervent
Radiol 200415793-800.
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TAGM vs. PVA

• Statistically significant TAGM more cc used
  (9.4 vs 3 cc), PVA higher cath occlusion (28 vs
  4). TAGM had higher symptom score change
  (started off worse). PVA had more complete
  infarction of dominant fibroid (95 vs 82).
• Equivalent Spasm rate, pain scores 1wk 3m,
  narcotic requirements, symptom scores 1wk 3m.
  Qof L total score. Amenorrhea rate.
• Trend More uninfarcted nondominant fibroids with
  PVA (20 vs. 8).

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ResultsProcedure Details
16
ResultsShort-term Outcomes
17
Results3 Months
18
ResultsImaging Outcome
19
Contour SE

• Marketed as a Embospheres-like sphere made of
  PVA. Easy to inject.
• Specific-label approval by FDA for uterine
  embolization.
• Questions have arisen about effectiveness
• Repeated study for sPVA vs Embospheres
• Randomized to either embolic
• Patient, research nurse blinded to embolic
• Review of pre and post embo MRIs blinded to
  embolic.
• Spies JB, et al. Spherical Polyvinyl Alcohol
  versus Tris-acryl Gelatin Microspheres for
  Uterine Artery Embolization for Leiomyomas
  Results of a Limited Randomized Comparative
  Study. J Vasc Intervent Radiol, in press.

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Results

• 36 patients enrolled 17 with Contour SE and 19
  with Embospheres.
• Enrollment stopped based on initial findings.
• No difference in short-term measures.
• Embospheres advantage quality of life scores at 3
  months. (91.9 vs 78.1, p 0.02).
• Among 19 patients with imaging follow-up, Contour
  less likely to infarct all fibroids (1 of 14 for
  Contour vs 6 of 11 for Embospheres, P 0.02).
• Contour SE had greater percent unifarcted (mean
  48 for Contour SE vs 5 for Embospheres,
  Plt0.001).

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sPVA 90 uninfarcted
Pre
Post
22
Embosphere 30 uninfarcted
Pre
Post
23
sPVA vs. PVA

• Levin SIR 05 presentation
• -23 pts. 500-700 sPVA and 23 350-500 PVA.
• -Similar baseline ut. volumes, or size of
  fibroids.
• -?embo light or stasis.
• -sPVA 3.7 x more likely to have persistently
  enhancing fibroids than PVA.
• -(Ut. size avg. decrease of 16 sPVA 28 PVA)

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sPVA

• Siskin, SIR05 presentation
• -124 pts but only 69 had MRI.
• -500-700m sPVA to complete stasis.
• -100 infarction in only 35/69 (51).

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Initial Conclusions

• Short term imaging outcome shows frequent poor
  results from sPVA.
• Difference statistically significant (Spies
  data), although still a small sample.
• Likely mechanism is redistribution after
  embolization.
• Primary Contour size was 500-700. Larger size
  embolic may be more effective, although no
  published data to support (Pelage unpublished
  data).

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Refined Protocol for sPVA

• Unpublished data Pelage, SIR 05 presentation
  that followed Levin
• -2 groups of 23 pts.
• -Grp 1 sPVA, 500-700m, embo light
• -Grp 2 sPVA, 700-900m up, embo to stasis
• (Increase UA viz 5?10 cardiac beats leave
  catheter in place for 5 re-check)
• -19/23 (83) complete fibroid infarction in grp
  2 vs. only 2/23 (9) in grp 1.

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Bead Block

• Similar to spherical PVA.
• No clinical studies demonstrating its
  effectiveness compared to other materials.
• Terumo IR Survey 312 IR professionals polled _at_
  SIR 2005, 72 said that Bead Block is superior to
  other embolics (26 same, 2 inferior).

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Bead Block (cont)

• No published studies on its effectiveness.
• (Kroencke ISET 05 presentation 42 pts, 500-700m
  up to 6cc then upsize, embo light initially
  then extended study to increase infarction rate
  by changing to near stasis and upsizing. 74 had
  90-100 infarction).
• Given concerns regarding spherical PVA, careful
  assessment of the extent of fibroid infarction
  with contrast-enhanced MRI essential.

29
Gelfoam

• Essentially no published data on its
  effectiveness.
• Abstract by Katsumori et al SIR 05 in long-term
  outcomes. 85 pts (17 lost to f/u, similar symptom
  control, somewhat less failure _at_ 5 yr (11.5 vs.
  20).
• No data to support contention that since it is
  temporary agent it is better for patients
  interested in pregnancy (2 pts pregnant, both
  miscarried).
• May be as likely or more to result in uterine
  artery occlusion than other materials.
• Needs further study.

30
Embogold

• Essentially the same as Embospheres but with
  elemental gold added.
• Likely same effectiveness profile as Embospheres.
• Associated with recurrent pain, low grade fevers
  and rash in higher than expected number of UAE
  patients.
• No longer recommended by manufacturer for UAE.
• Should not be used for UAE.

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Conclusions

• In early years of UAE, there was little data to
  suggest that the embolic type impacted outcome.
• Recent experience with newer embolics suggests
  that embolic characteristics do impact
  effectiveness through incomplete fibroid
  infarction.
• Prior to acceptance of new embolics, need quality
  imaging data with follow-up contrast-enhanced MRI
  to insure complete fibroid infarction.