New genetic test predicts risk of metastasis in patients with deadly eye cancer

Imagine being diagnosed with eye cancer – but your doctor can't tell whether you have the aggressive type that will swiftly spread, causing blindness and death in as early as a year.

A new procedure at UCLA's Jules Stein Eye Institute could reveal this valuable information to ocular melanoma patients and their physicians, providing a clear basis for making treatment and lifestyle choices. Researchers have pioneered the first technique to biopsy tissue from the living eye in order to predict which tumors possess high metastatic risk. The Nov. 15 online edition of the journal Ophthalmology reports the findings, which urge a new treatment strategy for physicians and offer huge medical and psychological benefits to patients.

“For the first time, we have demonstrated that it's safe and feasible to perform a biopsy in the living eye to obtain clear results about whether a tumor has metastatic potential or not,” explained Dr. Tara Young, assistant professor of ophthalmology at UCLA's Jules Stein Eye Institute and a Jonsson Comprehensive Cancer Center researcher. “Identifying patients at high risk for metastasis is an important first step toward reducing the death rate of this cancer, which kills nearly half of its patients.”

Ocular melanoma attacks the pigment cells in the retina. Earlier studies discovered that patients who are missing one copy of chromosome 3 in their tumor tissue are more likely to have highly aggressive cancers. Half of these patients die within five years, due to metastasis to the liver and other organs.

Using this genetic marker as the starting point for their research, UCLA scientists studied a group of patients who had been newly diagnosed with ocular melanoma. Each patient was scheduled for a standard eye surgery to temporarily implant a small disc designed to shrink the tumor with radiation and hopefully save the eye.

For the first time, UCLA surgeons used an ultra-fine needle to collect cells from the cancer before surgery and send the sample to the lab for culture. After growing the tumor cells, a geneticist analyzed them to determine whether they were missing a copy of chromosome 3.

Of the nine patients in the UCLA study who underwent biopsy, four had tumors identified as high-risk for aggressive metastasis, and five were identified as low-risk.

“When physicians know upfront which patient has a poor prognosis, they will monitor the person more closely to detect metastasis earlier and consider more aggressive treatments to increase their chance of survival,” Young emphasized. “Knowledge of metastatic risk will also help patients and their physicians decide whether to pursue clinical trials of experimental therapies that target metastasis.

“Patients understand that no good treatment exists after their cancer spreads — everyone wants to know what their metastasis risk is,” she added. “If the risk is low, it's a giant relief and emotional burden off their shoulders. If the risk is high, it enables them to plan arrangements for their family and finances, and make the most of their remaining time alive.”

Pioneered by UCLA ophthalmic pathologist Dr. Ben Glasgow, the technique of fine-needle aspiration for collecting cancer cells from the living eye has been the standard of care at the Jules Stein Eye Institute since 2004, but adopted by only a handful of other ophthalmic centers in the nation.

“Until now, there's been little we could do but radiate the patient's eye and ask them to return for a follow-up exam in six months,” observed Young. “But it's short-sighted to think of ocular melanoma as related only to the eyeball. Cancer can kill you, regardless of where it originates in the body.

“We've known for 10 years that this genetic marker is linked to fast-growing melanoma,” she added. “It's time for ophthalmologists to expand their surgical practice to include the biopsy procedure, and use it to obtain life-saving information for their patients. Only then will we be able to develop strategic approaches to treating the cancer's effect on the whole body.”

Although rare, ocular melanoma is the most common eye cancer to strike adults. The National Eye Institute reports some 2,000 newly diagnosed cases of the cancer – roughly seven in 1 million people — per year in the United States and Canada. The disease spans the age and ethnic spectrum, and is not hereditary.