Strategies to Minimize Radiation Maculopathy
Yonah ZiembaSKMC, MS3
Radiotherapy for Uveal Melanoma:
OutlineI. Patient presentation
II. 3 Treatment Options: Plaque vs Proton Beam vs
Enucleation
III. 3 Clinical Questions, 3 Major Studies
IV. Back to the Patient
• US incidence 1,500 cases/year.• White >> Black, Men > Women • Melanoma is the most common primary
intraocular malignancy in adults, at 75%.• #2 = Retinoblastoma. Only 13%.
Epidemiology
Patient Presentation
• JK is a 51y/o gentleman presenting w 3 mo of intermittent photopsia in the left eye.
• Exposure to arc welding.• Choroidal lesion measuring 10 x 8 mm in
left eye noted on Fundus exam.• Visual acuity was 20/20.
Fundus Exam
Fluorescein Angiography Ultrasound
• Work-up: fundus exam, ultrasound and fluorescein angiography.
• Measurements: diameter by fundus exam, thickness by ultrasound
• Biopsy: not done until after radiation for risk of seeding.
Diagnosis
3 Treatment Options• Enucleation
Last resort
• Proton BeamUseful when > 5 mm thickness
• Plaque Brachytherapy Useful when < 5 mm
thickness
• prior to 1970
• refractory cases
Enucleation
Enucleation and Prosthesis
Proton Beam
Plaque
Plaque
• Most common form of treatment• Good for thin tumors, not thick tumors
Plaque
• Commonly Iodine-125 T1/2: 59.4 d
Av Energy: 35.5 keV
• Not possible over optic nerve due to anatomy
3 Clinical Questions
I. Is radiation effective?
II. Does radiation cause vision loss?
III. Can prophylaxis prevent vision loss?
• Question: Is Radiotherapy as effective as enucleation?
• Design: Randomized multi-center clinical trial of iodine 125 brachytherapy vs enucleation.
• Conclusion: No difference in survival betweenI-125 brachytherapy vs enucleation.
• Impact: Brachytherapy usually first line treatment.
JAMA Ophthalmology, Dec 2006
JAMA Ophthalmology, Sept 2000
J of Ophthalmology Vol 121, Jan 2014
Back to our patient…• JK’s melanoma was treated with iodine-125
plaque. 7185 cGy to the apex and 17,023 cGy to the base of the tumor.
• 3355 cGy was delivered to the fovea and4235 cGy to the optic disc.
• To minimize maculopathy, JK received anti-angiogenic treatment.
• Bevacizumab injections• Photocoagulation (laser)
• Lesion reduced to a 3 mm scar
Before After
2 Year Follow Up
• Patient retained perfect 20/20 vision!• Attributed to the anti-angiogenic treatment. • Case was published as a success story
in Retina Today.
Retina Today, March 2013
ConclusionsI. Wills Eye protocol for work-up of non-metastatic
melanoma differs from other tumors: - No biopsy, CT or MRI- Diagnosis via fundus exam- Thickness measured by ultrasound
II. Isodose patterns of Plaque vs Proton: - Plaque ➞ Steep gradient ➞ Thin tumors- Proton Beam ➞ Wide plateau ➞ Thick tumors.
III. Radiotherapy cures ocular tumors, yet causes maculopathy
IV. Bevacizumab expected minimize maculopathy- Too early for long term studies
Thank you!
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