2020–2021 BCSC Basic and Clinical Science Course™
4 Ophthalmic Pathology and Intraocular Tumors
Part II: Intraocular Tumors: Clinical Aspects
Chapter 17: Melanocytic Tumors
Melanoma of the Choroid and Ciliary Body
Prognosis and Prognostic Factors
There are 6 main clinical risk factors for melanoma-related mortality:
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larger tumor size (part of AJCC staging)
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ciliary body extension (part of AJCC staging)
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extraocular extension (part of AJCC staging)
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older age
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faster tumor growth
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tumor regrowth after globe-conserving therapy, especially radiotherapy
The histologic and molecular features associated with a higher rate of metastases include the following:
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epithelioid melanoma cells
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high mitotic or cell proliferation index
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specific extravascular matrix patterns (loops and networks of loops) and high microvascular density
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mean diameter of the 10 largest nucleoli
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large numbers of tumor-infiltrating lymphocytes and histiocytes (macrophages)
The prognostic factors most strongly associated with risk of metastasis are genetic:
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monosomy 3, especially with gains in chromosome 8
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gene expression profiling class 2 and, to a lesser extent, class 1B
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BAP1 mutation within tumor tissue
See Table 17-4 (earlier in the chapter), which lists 10-year survival estimates according to the evidence-based staging system of the AJCC Cancer Staging Manual, 8th Edition. Stage IV implies that lymph node involvement or metastasis is present at the time of diagnosis of the primary tumor.
See Chapter 12 for a more detailed discussion of the histologic and molecular prognostic factors for uveal melanoma.
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Damato B, Eleuteri A, Taktak AF, Coupland SE. Estimating prognosis for survival after treatment of choroidal melanoma. Prog Retin Eye Res. 2011;30(5):285–295.
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Edge S, Byrd DR, Compton CC, Fritz AG, Greene FL, Trotti A, eds. Malignant melanoma of the uvea. In: AJCC Cancer Staging Manual. 7th ed. Springer; 2010:part X, pp 547–559.
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Harbour JW. Molecular prognostic testing and individualized patient care in uveal melanoma. Am J Ophthalmol. 2009;148(6):823–829.
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Shields CL, Furuta M, Thangappan A, et al. Metastasis of uveal melanoma millimeter-by-millimeter in 8033 consecutive eyes. Arch Ophthalmol. 2009;127(8):989–998.
Collaborative Ocular Melanoma Study
Data from the prospective, randomized, international COMS trial provide an additional framework for patient discussions concerning long-term survival and rates of globe conservation with enucleation and iodine 125 brachytherapy. See the sidebar on the following page for details.
Excerpted from BCSC 2020-2021 series: Section 4 - Ophthalmic Pathology and Intraocular Tumors. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.