New treatment for retinal tumor should be used with caution
Intra-arterial chemotherapy (IAC) for treatment of retinoblastoma demonstrated a variable response rate but also evidence of ocular complications in a recent study.
In IAC, a new but somewhat controversial treatment for retinoblastoma, medication is administered through the ophthalmic artery. According to a research team led by Ralph C. Eagle, Jr., MD, of the Wills Eye Institute in Philadelphia, Pennsylvania, the main goal of delivering treatment directly to the eye is to provide sufficient drugs to eradicate the retinoblastoma while avoiding the toxicities of systemic chemotherapy.
As the investigators reported in Archives of Ophthalmology, they studied eight eyes that had been treated with IAC but later removed due to a lack of response to therapy or because other medical problems developed, such as a certain type of glaucoma. Dissection and analysis of the eyes by an ophthalmic pathologist revealed minimal response to therapy in one eye, moderate response in one eye, extensive response in four eyes, and complete regression in two eyes.
However, the eyes also showed evidence of complications, including ischemic atrophy involving the outer retina and choroid in four eyes, and—in five cases—blood clots in blood vessels, and foreign material within those clots.
“Retinoblastoma can be controlled with IAC, but histopathology of [removed] eyes reveals that ocular complications including thromboembolic events can occur,” concluded the authors, who suggest that IAC therefore be used with caution despite evidence that the treatment can result in complete tumor regression.