Fine-needle aspiration biopsy may help determine metastasis risk in choroidal melanoma

Fine-needle aspiration biopsy and fluorescent in situ hybridization may provide important information for the management of patients with choroidal melanoma, a study suggests. The fine-needle biopsy was performed before placement of radioactive plaque for local treatment of the tumor.

The fluorescent in situ hybridization (FISH) technique is promising for detecting monosomy 3, a strong genetic marker for high risk of systemic metastasis, the study authors said. The genetic test may help predict patients' risk for metastasis.

Tara A. Young, MD, PhD, and colleagues at the Jules Stein Eye Institute in Los Angeles evaluated the feasibility of 30-gauge fine-needle aspiration biopsy in 18 eyes of 18 patients with choroidal melanoma. The biopsy specimens were subjected to FISH to determine patients' monosomy 3 status.

Previous studies have shown that choroidal melanoma patients who are missing one copy of chromosome 3 have up to a 70% chance of death from disease metastasis within 4 years after ocular treatment, according to the study authors.

"Until recently, determining the prognosis of patients receiving treatment for choroidal melanoma has relied upon the clinical and histopathologic characteristics of the tumor. However, these features ... are problematic, not only because enucleated specimens may be required, but also because their ability to identify patients at high risk for metastatic disease is limited," Dr. Young and colleagues said.

The biopsy technique, developed by an ocular pathologist at the university, has been performed at Jules Stein since 2004. In the current study, Dr. Young performed all 18 biopsies using a 30-gauge needle inserted via a tangential transscleral approach. Cells were aspirated into a 10 cm³ syringe.

The biopsies provided a cytologic diagnosis of melanoma in 14 of 18 patients (78%) and a diagnosis with respect to monosomy 3 in nine of the 18 patients (50%). Of those nine patients, four (44%) were positive for monosomy 3, the authors reported.

"Our preference remains a tangential transscleral approach without a scleral flap because it is direct, the tract is self-sealing, the sclera remains satisfactory for subsequent plaque placement, and it does not violate the retina as would a transvitreal intraocular approach," the authors said.

In a press release from UCLA, Dr. Young said, "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."

The study is published in the November 15 online edition of Ophthalmology.