According to a study report published online by Archives of Ophthalmology, one of the JAMA/Archives journals, eight eyes with retinoblastoma (a tumor of the retina of the eye) that were treated by intra-arterial chemotherapy (IAC), post-removal, showed evidence of ocular complications and variable response of the tumor to the treatment.

Intra-arterial chemotherapy (IAC) is a novel but controversial treatment for retinoblastoma (Rb), as stated in the background information in the article. In this kind of treatment, the medication is directly administered into the eye and its neighboring areas via ophthalmic artery.

The researchers explained:

“The main goal of this approach is to provide sufficient chemotherapy to eradicate the Rb and avoid the toxicities of systemic chemotherapy.”

Eight eyes treated with IAC but enucleated (removed) were examined by Ralph C. Eagle, Jr., M.D., Wills Eye Institute, Philadelphia and his colleagues. The enucleations were performed either because of serious medical problems such as glaucoma developed or because the tumors were not reacting to therapy.

After dissection and thoroughly studying each eye, the ophthalmic pathologists found out that the response of the eyes to therapy ranged from minimal (one eye), to moderate (one eye), to extensive (four eyes) to complete regression (two eyes).

It was also seen that ischemia, atrophy of the retina, blood clots in blood vessels and presence of foreign material within those clots, were among the other complications that were quite evident in most of the examined eyes.

The scientists wrote:

“In summary, histopathology of eyes with Rb following IAC showed evidence of complete tumor regression in eyes in which there was clinical tumor regression and also confirmed viable tumor in those in which tumor was suspected clinically.”

Although tumor regression was seen in the eyes, the authors have stressed upon the significance of the discovery of blockages within the blood vessels and the presence of foreign material in the clots of these vessels.

The investigators conclude:

“Retinoblastoma can be controlled with IAC, but histopathology of enucleated eyes reveals that ocular complications including thromboembolic events can occur.”

“Histopathologic Observations After Intra-arterial Chemotherapy for Retinoblastoma”
Ralph C. Eagle Jr, MD; Carol L. Shields, MD; Carlos Bianciotto, MD; Pascal Jabbour, MD; Jerry A. Shields, MD
Arch Ophthalmol. Published online July 11, 2011. doi:10.1001/archophthalmol.2011.223

Written by: Anne Hudsmith