Skin Cancer of the Eye – Uveal Melanoma

MD Anderson Cancer Center
Date: 02-13-2012

 

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Lisa Garvin: Welcome to Cancer Newsline, a podcast series from the University of Texas M.D. Anderson Cancer Center. Cancer Newsline helps you stay current with the news on cancer research, diagnosis, treatment and prevention providing the latest information on reducing your family's cancer risk. I'm your host Lisa Garvin. Today we'll be talking about a particular type of eye cancer called uveal melanoma. Our guest to address this topic is Dr. Sapna Patel. She's an Assistant Professor of Melanoma Medical Oncology here at M.D. Anderson. Welcome Dr. Patel.

Dr. Sapna Patel: Thank you Lisa, thank you for having me.

Lisa Garvin: Let's start with an anatomy lesson, what is the uvea of the eye?

Dr. Sapna Patel: So the uvea of the eye makes up the back part of the eye that you cannot see. It's usually examined by a specialist known as a retinal ophthalmologist and the back most part of the uvea is the choroid. This lays behind the retina. Moving forward is the ciliary body and this is a group of muscles that controls dilation of the pupil. In the front of the eye is the iris which is also part of the uvea and this is the color portion of the person's eye.

Lisa Garvin: Now some people ask, how do you get cancer generally known for skin in the eye?

Dr. Sapna Patel: Well, that's actually a really controversial area. What we think is UV radiation may play a role in this type of cancer similar to skin cancer but it's a little bit unclear. What is seen is that uveal melanoma is--occurs in a higher frequency in the country of Australia. This is a country that also has a higher frequency of skin melanoma and they also happen to have a hole over their ozone layer, so possibly due to lack of sun protection from the ozone layer, UV radiation penetrates the eye and affects carcinogenesis in the eye.

Lisa Garvin: How--eye cancers taken as a whole are fairly rare, how rare is uveal melanoma in the spectrum of eye cancers?

Dr. Sapna Patel: That's a great question. Retinoblastoma is the most common pediatric malignancy in the eye and uveal melanoma is the most common intraocular malignancy in adults. It actually represents about 5 to 6 percent of all melanomas and as such is the second most common type of melanoma after cutaneous or skin melanoma.

Lisa Garvin: How do--it sounds like because we talked about Australia being a big risk group, are there known risk factors and are they similar to the skin, cutaneous melanoma?

Dr. Sapna Patel: Yeah, we think they probably are similar. Again, these are risk factors that puts you at a higher increased risked for skin cancer such as having light skin. Light-skinned patients usually have light irises or blue, green, light brown irises. These probably contain less melanocytes and therefore less protection from UV radiation. Also, people who are prone to freckles on their skin also interestingly have freckles in the back of their eye in the uvea. Again, these are usually only seen with the dilated ophthalmological exam not necessarily with an optometry exam.

Lisa Garvin: Obviously, because it's at the part of the eye that you can't see, we think that the symptoms are pretty cryptic. I mean, probably not very obvious.

Dr. Sapna Patel: Yeah, it's true, so a lot of these patients are just picked up on their yearly eye exam by an ophthalmologist who dilates the eye and watches a freckle overtime. A freckle is also known as a nevus whether it's in the skin or whether it's in the eye, so an ophthalmologist will often say you have a nevus and I'm gonna watch it. Certain ophthalmologists can do different measurements such as ultrasound or echography to define the characteristics of this nevus. If that nevus changes overtime then it's usually considered a melanoma. Other patients actually will have symptoms and they'll have flashes or floaters that will become more persistent. I think we all probably are used to that sensation of amoebas or floating little squigglies coming into our line of view but those are transient, usually intermittent and very rare, the episodes. If these become more frequent or more persistent that may be a reason to get your eyes checked out.

Lisa Garvin: Is there--are there symptoms like intraocular eye pressure that may cause the eye to bulge or be painful?

Dr. Sapna Patel: Usually, those occur with the more anterior uveal tumors or the ciliary body tumors. When you have a tumor at the ciliary body, which is the muscle that controls the dilation of the pupil, it can cause pressure and build up of pressure in the eye. So there are times that patients will present with that but those are exceedingly rare.

Lisa Garvin: Well, what about those people who don't wear glasses or don't require yearly eye exams, is there any way for them to know or--

Dr. Sapna Patel: You know I actually feel--I have a new way of thinking about this. My sister is the one person in our family who does not have glasses so she never has her eyes checked out but now I know there are many things that happen in the back of the eye that should be watched. Nevus or freckles, certainly, these melanomas and other things such as retinopathy or increased vascular proliferation, these are signs and symptom--these are conditions that may not have any signs or symptoms. So a yearly eye exam is probably a good thing to do just like the twice a year dental visit.

Lisa Garvin: Now when they come to M.D. Anderson are you catching them at all stages, do they tend to be more advanced or all across the spectrum?

Dr. Sapna Patel: By and large they're early stage so usually these patients touch base at M.D. Anderson with our ophthalmologists. It's very rare for uveal melanoma to be metastatic at the time the primary cancer is diagnosed so usually what they do is they come and see the ophthalmologist and have their eye treated and they then follow up with the medical oncologist to monitor to see if this cancer will spread.

Lisa Garvin: With melanoma, generally, surgery is the front line treatment. Obviously, you've got the site preservation to worry about, how do you treat uveal melanomas typically?

Dr. Sapna Patel: Well, surgery is actually still a mainstay of this type of cancer as well. Years ago there is a group of experts in this field known as the Collaborative Ocular Melanoma Society and they've performed numerous studies over the years regarding how to treat uveal melanoma. What they decided was based on size criteria, mostly how thick is the lesion and actually, this is the same criteria we use, similar criteria we use for skin melanoma. Based on thickness you're deemed as having either a small, medium or large uveal melanomas. Small uveal melanomas can be watched and observed overtime, they don't need emergent treatment. Medium uveal melanomas can be treated either with a nucleation or removal of the eye or they can be treated with what we call radiotherapy. Radiotherapy in this sense usually involves sewing or gold disc on to the eye that emits radiation slowly into the tumor bed for a period of about 5days. This occurs also with the ophthalmologist and the radiation therapist in conjunction. After that plaque or that gold disc is removed, the tumor slowly disintegrates over time and the eye can be preserved. Interestingly though, vision can often be compromised so in some cases removing the eye outright might be the right choice. For a large uveal melanoma a nucleation or removal of the eye is the standard therapy.

Lisa Garvin: And that requires taking everything out, the entire eyeball so the whole orbit of the skull is pretty much cleaned out?

Dr. Sapna Patel: Right. Essentially, the actual ball or the globe of the eye is removed. The eye socket is left in place, a conformer can then be put in and actually, Lisa, you would be amazed if you saw these patients, the work of ocularist who are the professionals who make the prosthetics is unbelievable, they're literally artists, and I often frankly find myself looking at a patient and saying which eye is your good eye and which eye is the prosthetic eye? You cannot tell. They matched the gradations on the iris to the other eye. They're really, really wonderful, wonderful professionals to have as part of the team.

Lisa Garvin: I mean the old joke and for those of us who remember Columbo, Peter Falk had a glass eye back in the '70s, are they glass?

Dr. Sapna Patel: You know that's a good question, I actually don't know the answer. I really don't know the answer. The ocularist would probably know that.

Lisa Garvin: But they could--obviously, they've lost the sight of that one eye so they lose the depth perception but isn't it at some point you can kind of train the muscles to kinda move the eye in conjunction with your good eye?

Dr. Sapna Patel: That usually the prosthetics do not move so a traditional ocularist will fit a prosthetic that does not have any muscle capabilities. There are some very advanced prosthetics though that are able to move with the good eye.

Lisa Garvin: In what instances are you able to preserve the eye?

Dr. Sapna Patel: Well, and generally--generally you preserve it for a medium or small uveal melanoma and depending on the anatomical location in the choroid or the uvea for some of these tumors, preservation of the eye can occur. If the tumor is occurring too close to the optic nerve, which comes out at the back of the eye, then usually eye preservation is difficult because you cannot appropriately radiate this area. You don't want radiation to touch your optic nerve because then you will lose vision anyway and so, if the tumor is too close to the optic nerve, eye preservation is more challenging.

Lisa Garvin: And when you say that when you do preserve the eye there are still visual issues or vision issues, what would those be?

Dr. Sapna Patel: Technically, they're known as radiation retinopathy and you can have some irritation to the macula, so what my patients usually complain about is persistent double vision or blurry vision and still persistent depth perception on the eye that's affected.

Lisa Garvin: So it sounds like the message here, Dr. Patel, is get those eyes examined.

Dr. Sapna Patel: I agree. I think that's really true. I think those of us that do wear glasses or corrective lenses should have them examined regularly but even those that do not, probably at some interval maybe yearly or every couple of years could use a dilated retinal exam.

Lisa Garvin: And of course we can't slap sun, you know, lotion on our eyes, do sunglasses help and do they need to be a particular type of sunglasses?

Dr. Sapna Patel: They do help actually, you know by blocking the UVA and UVB rays, good UV protective sunglasses help. There are fancy sunglasses that actually help to diminish--polarize the light and diminish the UVA and UVB but in general, any dark lenses will help do that.

Lisa Garvin: Thank you Dr. Patel for that good advice. If you have questions about anything you've heard today on Cancer Newsline, contact Ask M.D. Anderson at 1-877-MDA-6789 or online at www.mdanderson.org/ask. Thank you for listening to this episode of Cancer Newsline. Tune in for the next podcast in our series.

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