Does Saving the Eye Compromise Survival?
July 16, 2001 – Being diagnosed with cancer is scary enough. But when the treatment involves removing the cancerous tumor — as it often does — and that tumor is in the eye, the treatment, for some, can sound even more frightening than the diagnosis.
But thanks to the results of a new study, some patients with primary eye cancer have an alternative that has for the first time been shown to offer a similar survival rate to removing the eye.
“The study is looking at one of the most severe forms of cancers that can affect the visual system, called choroidal melanoma,” Paul A. Sieving MD, PhD, tells WebMD. “Melanoma is a pigment cancer that [is] active in the pigmented cells in the back of the eye, called choroidal cells. The health liability for cancer is that cancers can spread and ultimately kill the person,” meaning that left untreated, the person may lose more than just their eye. Sieving, who is not involved in the study, is the director of the NIH’s National Eye Institute, which helped fund the study.
“This disease is similar to malignant melanoma as most people know it, which occurs in the skin and soft tissues,” Barbara S. Hawkins, PhD, tells WebMD. Hawkins, a professor of ophthalmology and the director of the Clinical Trials and Biometry division in the department of ophthalmology at the Johns Hopkins Medical Institutions in Baltimore, is the principal investigator in the trial’s coordinating center.
“The study was comparing two treatments that have been used by ophthalmologists for taking care of patients,” she says. The two treatments are: removing the eye, called enucleation, and I-125 brachytherapy, which involves placing a radioactive plaque on the tumor to shrink it.
“As long as the cancer is confined to eye, the idea had always been that if you take out eye, you take out cancer. About 20 years ago people began using radiation to take care of these patients, because people don’t want to lose their eye,” says Hawkins. “Some people were very much in favor of radiation, others were worried that the radiation would make the patient’s life shorter because you would not be taking the cancer out. Physicians wanted to make sure they weren’t sacrificing length of life just to retain vision.”
To see which treatment offered better survival, over the course of 12 years researchers from 43 clinics around the country studied more than 1,300 patients with medium-sized choroidal melanomas. Patients were randomly assigned to either having their cancerous eye removed, or I-125 brachytherapy. Eighty percent of the patients were followed for at least five years, and about a third were followed for 10 years or longer.
The researchers showed that the result of each treatment was almost identical; the five-year survival rates were about 82%.
“Statistically and clinically there is no meaningful difference in survival between the two treatments. That is what the melanoma study has been able to show,” says Hawkins. “This is the first study where patients were … followed long enough to know whether their survival was threatened.”
But choosing radiation over enucleation was no guarantee of 20/20 vision — or even any vision in the cancerous eye, for that matter. Some patients who underwent radiation had a recurrence, and later underwent surgery to remove the eye. Other radiation patients experienced vision loss despite saving their eye.
“The best news from [this study] is that radiation treatment, at least as given [in the trial] … does not threaten the length of remaining lifetime,” says Hawkins. “The second good piece of news is …[that] this treatment is now available relatively close to patients all over North America. Now patients have equal access to both types of treatment, so it is the patient’s choice: some patients don’t like the idea of having a cancer in their body and they want the eye removed; others want to save their eye at all cost.”