NOV 20, 2018
This study retrospectively assessed the risk of ophthalmic vascular events following intra-arterial chemotherapy (IAC) for retinoblastoma.
Researchers reviewed patients who received at least 3 cycles of unilateral IAC as a primary treatment between January 2009 and November 2017.
Patients were divided into 2 groups due to a change in catheterization technique in 2010. Twenty-two eyes were treated between 2009 and 2011 (early IAC era) and 54 eyes were treated between 2012 and 2017 (recent IAC era). There were no significant difference in age, sex or tumor features between the two groups. Treatment during the early IAC era included melphalan, topotecan and carboplatin, but there were no carboplatin infusions during the recent IAC era.
Patients treated prior to 2012 received fewer infusions (2.6 vs. 3.4; P=0.02) and were more likely to receive either melphalan alone or with carboplatin (both P<0.01). Ophthalmic vascular events declined over time and were less frequent in patients treated after 2011 (59% vs. 9% per eye, 23% vs. 3% per infusion; P<0.01). Peripheral retinal nonperfusion, vitreous hemorrhage, subretinal hemorrhage, branch retinal vein occlusion and choroidal ischemia were all reduced in the recent IAC era, but only ophthalmic artery spasm/occlusion was statistically significantly different from the early IAC era (27% vs. 0%; P<0.01).
Vascular events did not correlate with patient age, tumor features, number of infusions or total cumulative infusion dosage of melphalan or topotecan. All 4 patients who received carboplatin experienced an event (choroidal ischemia or ophthalmic artery occlusion).
This study is limited in its retrospective design. Although the authors were selective and only assessed patients who received IAC as primary treatment, each individual may have received different focal therapies that could have confounded the results. This study highlights a very important decline in vascular events in the recent years but the reason remains unknown. As suggested, the change in technique in 2010 and reduced frequency of carboplatin use—which increases rate of vascular events—may have contributed to the decline. Other medical co-morbidities that may lead to hypercoagulable state have not been examined.
Despite a higher number of infusions and drug exposures, patients with unilateral retinoblastoma treated with primary IAC in recent years have a lower number of ophthalmic vascular events than those treated prior to 2012.