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Choroidal Melanoma Treated With Cryotherapy
Arch Ophthalmol. 2002;120:393-395.
The treatment of small choroidal melanocytic tumors is evolving because
of the recognition of risk factors for growth and metastasis.1-3
Ideally, the treatment of small melanocytic tumors would completely eradicate
the tumor without compromising visual acuity. Cryotherapy has been used in
a limited fashion for the treatment of choroidal melanomas.4-6
Lincoff et al4 and Brovkina et al5 evaluated cryotherapy in small series of patients
with medium-sized and large melanomas, but exudative retinal detachment and
incomplete tumor destruction compromised treatment. We report the clinical
and histopathologic findings in a patient treated with cryotherapy for a small,
growing choroidal melanocytic tumor 125 months before death from unrelated
causes.
Report of a Case
The patient was initially seen in August 1988 for a routine eye examination
and was found to have a pigmented juxtapapillary choroidal lesion (Figure 1). By January 24, 1989, the lesion
had clearly enlarged. Examination at that time showed visual acuity of 20/20
and a normal anterior segment. A pigmented juxtapapillary lesion was located
inferonasal and adjacent to the optic nerve (Figure 2). Echography demonstrated that the tumor measured 1.8 mm
in thickness, 7.5 mm in longitudinal diameter, and 6.0 mm in transverse diameter.
The patient was enrolled in a trial of cryotherapy for treatment of small
choroidal melanocytic tumors, and the tumor was treated on March 15, 1989,
using a double freeze-thaw cryotherapy with a conventional retinal cryoprobe.
The optic nerve was included in the treatment. On the first postoperative
day, the patient's vision was no light perception. The tumor diminished in
thickness, but a small area of pigmentation remained in the center of the
treatment scar. This area of pigmentation was treated again on August 10,
1993. The tumor regressed to a flat chorioretinal scar after the second cryotherapy
treatment. Periodic liver function tests and chest x-ray films were obtained
and indicated no suggestion of metastatic disease. There was no clinical evidence
of recurrence of the tumor (Figure 3).
The patient died of cardiovascular disease 125 months after his initial treatment.
No autopsy was performed, but the eyes were obtained for histopathologic study.
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Figure 1. Funduscopic appearance of peripapillary
pigmented lesion in August 1988.
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Figure 2. Funduscopic appearance of lesion
in January 1989 demonstrating enlargement of tumor. Note extension of the
tumor beyond the adjacent retinal vein.
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Figure 3. Funduscopic photograph of the
retinal and choroidal scar 6 years after cryotherapy to lesion. Note the pallor
of the optic nerve head.
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The left globe was fixed in 10% neutral buffered formalin and processed
for light microscopy. Serial sections were prepared through the entire extent
of the chorioretinal scar and studied for evidence of residual tumor.
Microscopic examination showed near full-thickness atrophy of the retina
and choroid in the area of the cryotherapy (Figure 4). The retina in the area of cryotherapy consisted of a
thin layer of glial cells with some migration of hyperplastic retinal pigment
epithelium into the retina (Figure 5).
There was a thin monolayer of cells on the surface of the retina (epiretinal
membrane). A few large vessels were present in the choroid, but there was
atrophy of the small and medium-sized choroidal blood vessels. Occasional
pigment-containing macrophages were found within the choroid, but no tumor
cells were present, and no tumor cells were evident in the sclera or retina.
The optic nerve was atrophic, and loss of axons and myelin and thickening
of the pial septae were evident (Figure 6). The sclera in the area of cryotherapy was of normal thickness
(Figure 7).
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Figure 4. Microscopic examination shows
the junction (arrowhead) of the treated (left side of figure) and untreated
(right side of figure) retina and choroid. Note the loss of all retinal layers
in the area of treatment. Also apparent is the loss of most of the choroidal
vessels, with preservation of some of the large choroidal vessels. The retina
and choroid are artefactitiously detached from the sclera (hematoxylin-eosin,
original magnification x200).
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Figure 5. Microscopic appearance of the
retina and choroid in the center of the area of cryotherapy, showing no remaining
tumor cells. The retina is reduced to a thin layer of cells and fibrous tissue.
A few pigmented macrophages are present within the retina and choroid. The
small and medium-sized choroidal blood vessels are absent, but a large choroidal
vessel remains (asterisk) (hematoxylin-eosin, original magnification x400).
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Figure 6. Microscopic examination shows
that the optic nerve is markedly atrophic. Marked thickening of the pial septae
is apparent, and only a few areas of myelinated nerve fibers remain (arrowhead)
(hematoxylin-eosin, original magnification x200).
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Figure 7. Microscopic examination shows
that the sclera in the area of treatment is of normal thickness; however,
the retina and choroid are markedly thinned (between arrowheads) (hematoxylin-eosin,
original magnification x200).
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Comment
The results of our histopathologic study of this case are consistent
with complete destruction of this small, growing choroidal melanoma by freezing.
Careful study of serial sections failed to disclose any remaining tumor cells.
Hidayat et al6 have reported the mechanism
of cellular injury in rapid freezing of uveal melanomas to be plasmalemmal
breaks, dissolution of cytoplasmic matrix, and damage to cellular organelles,
suggesting a lethal effect on melanoma cells.6
Similar mechanisms of cell injury were undoubtedly responsible for the damage
evident to the optic nerve and the retina overlying the tumor.
Exudative complications of cryotherapy that have been observed in the
treatment of medium-sized and large melanomas were not found in this case.
The lack of these complications may be due to the smaller size of the tumor
and to the sequential application of less intense cryotherapy than was used
in the earlier studies. Also, no apparent damage to the sclera occurred as
a result of the cryotherapy.
The complete tumor destruction seen in this case indicates that cryotherapy
may be useful as a primary treatment for small, growing choroidal melanomas
or as an adjunct for treating recurrences of melanomas treated primarily with
radioactive plaque.
AUTHOR INFORMATION
This study was supported in part by an unrestricted grant from Research
to Prevent Blindness, New York, NY.
David J. Wilson, MD;
Michael L. Klein, MD
Portland, Ore
Corresponding author and reprints: David J. Wilson, MD, Casey Eye
Institute, Oregon Health & Science University, 3375 SW Terwilliger Blvd,
Portland, OR 97201-4197 (e-mail: wilsonda{at}ohsu.edu).
REFERENCES
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1. Shields CL, Shields JA, Kiratli H, De Potter P, Cater JR. Risk factors for growth and metastasis of small choroidal melanocytic
lesions. Ophthalmology. 1995;102:1351-1361.
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2. McLean IW. In discussion of: Shields CL, Shields JA, Kiratli H, De Potter P, Cater
JR. Risk factors for growth and metastasis of small choroidal melanocytic
lesions. Ophthalmology. 1995;102:1351-1361.
3. Collaborative Ocular Melanoma Study Group. Factors predictive of growth and treatment of small choroidal melanoma:
COMS Report No. 5. Arch Ophthalmol. 1997;115:1537-1544.
ABSTRACT
4. Lincoff H, McLean J, Long R. The cryosurgical treatment of intraocular tumors. Am J Ophthalmol. 1967;63:389-399.
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5. Brovkina AF, Ziangirova GG, Kornarov BA. Cryodestruction of choroidal melanomas [in Russian]. Vestn Oftalmol. March-April 1977:61-63.
6. Hidayat AA, LaPiana FG, Kramer KK, Whitmore PV, Wertz FD, Rao NA. The effect of rapid freezing on uveal melanomas. Am J Ophthalmol. 1987;103:66-80.
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SECTION EDITOR: W. RICHARD GREEN, MD
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