Melanoma


Current Methods for the Diagnosis and Treatment of Choroidal Melanoma Vasileios Petousis, MD1


and Paul T Finger, MD2 1. Fellow; 2. Director, The New York Eye Cancer Center


Abstract


Choroidal melanoma is the most common primary intraocular malignancy. Diagnosis is performed by clinical evaluation: eye cancer specialists currently use multiple diagnostic techniques, including ophthalmoscopy, fundus autofluorescence imaging (FAF), fluorescein angiography (FA), and indocyanine green angiography (ICG), as well as optical coherence tomography (OCT). Tumor biopsy has recently become popular due to the availability of diagnostic cytogenetic features, touted as biomarkers for metastasis. Standard treatments include observation (select small melanomas and indeterminate tumors), radiation therapy (plaque, proton beam), eye wall resection, and removal of the eye. Of these, ophthalmic plaque radiation therapy has become the most common and widely available conservative treatment. Successful initial treatment offers the best chance to prevent subsequent metastasis. Metastatic choroidal melanoma is typically diagnosed by combinations of physical examination, hematologic surveys, abdominal radiographic imaging (ultrasound, magnetic resonance imaging, computed tomography), and positron emission tomography–computed tomography (PET/CT). Most often initially found in the liver, metastatic choroidal melanoma carries an unfavorable prognosis for life. Herein, we report on currently available methods of diagnosis and treatment for choroidal melanoma.


Keywords Choroid, melanoma, diagnosis, treatment, staging


Disclosure: Vasileios Petousis, MD, has received a fellowship grant from The Eye Cancer Foundation, Inc. Paul T Finger, MD, has no conflicts of interest to declare. Received: September 1, 2010 Accepted: September 1, 2011 Citation: US Ophthalmic Review, 2012;5(1):62–9 Correspondence: Paul T Finger, MD, The New York Eye Cancer Center, 115 East 61st Street, New York City, NY 10065. E: pfinger@eyecancer.com


Choroidal melanoma (CM) is both the most common form of uveal melanoma and the most frequent primary intraocular malignancy. There is a reported yearly incidence of 4–6 per million per year in the US and Europe. Of interest, Queensland, Australia (beneath the ozone hole) has the highest reported incidence (10 per million per year) worldwide.1 While ultraviolet (UV) radiation has been proved to play a role in the pathogenesis of cutaneous melanoma, the statistical link for CM has been less clear. Factors implicating UV radiation in the incidence of CM include an increased incidence in patients with blue irises, outdoor occupations, and that these tumors are most commonly found in the posterior uvea, the choroid.1


CMs can present with or without symptoms.2 Size, location, and


tumor-related secondary complications (e.g. detachment, hemorrhage, cataract, and glaucoma) are associated with a variety of clinical symptoms. Symptomless patients are typically discovered during the course of periodic ophthalmic examinations or incidentally when patients seek refraction. Once found, CMs are typically sent to regional referral centers where further evaluations include extended ophthalmoscopy and specialized photography (e.g. color imaging, fundus autofluorescent imaging [FAF], fluorescein angiography [FA], and indocyanine green angiography [ICG]), as well as optical coherence tomography (OCT).3–6 Each diagnostic method has been shown to offer unique capabilities to reveal the diagnostic characteristics of CM.


62


Radiographic studies, such as magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography–computed tomography (PET/CT) are also selectively employed to evaluate CM.7–11 However, these techniques are more commonly used for systemic screening for metastatic disease.12,13


CM treatment has evolved from primary enucleation and local resection to eye-, sight-, and vision-sparing radiotherapy techniques. Stallard introduced the first eye plaques.14


These first disk-shaped radiation


therapy devices contained cobalt-60 and were later replaced by ruthenium-106, iodine-125, and palladium-103 sources.15–17


Each


radionuclide offers a unique and different intraocular dose distribution. Select centers have also used external beam radiation therapy (EBRT). The most common eye- and vision-sparing EBRT is proton beam.18 forms of EBRT include the gamma-knife and stereotactic radiosurgery.19


More exotic


The Collaborative ocular melanoma study (COMS) was a three-arm trial that included two multicenter prospective randomized clinical studies. A 16-year effort, the COMS stands as the largest evidence-based study of CM. Of the three clinical arms, the small tumor study found that 31 % of small CMs were documented to grow over five years.20


The medium-sized


tumor trial found no survival benefit from enucleation (removal of the eye) versus episcleral iodine-125 plaque irradiation.16


The large CM study (an indirect test of the Zimmerman Hypothesis: that enucleation surgery © TOUCH BRIEFINGS 2012


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76