Intra-arterial chemotherapy for retinoblastoma treatment in Chile: Experience and results 2013-2020

OBJECTIVE

To establish the success rate of salvage intra-arterial chemotherapy (IAC), defined as the percentage of eyes that achieved tumoral remission and avoided enucleation. The second objective was the clinical characterization, catheterization results, and associated local and systemic complications.

METHODS

Retrospective, interventional case series of 29 patients (35 eyes) with persistent or recurrent retinoblastoma.

RESULTS

A total of 73 salvage IAC procedures with topotecan and melphalan were carried out. Success rate was 77% at a mean follow-up of 41.4 months. All patients with only one remaining eye avoided enucleation (10 cases). Catheterization was successful in 98.6% of cases. The types of catheterizations were as follows: 71.2% supraselective ophthalmic artery, 12.3% occlusion pump assisted supraselective ophthalmic artery, 16.4% selective external carotid with retrograde flow. 14% of patients suffered local adverse effects: 1 (2.8%) transitory ptosis, 1 (2.8%) transitory oculomotor nerve palsy, 2 (5.7%) aseptic cellulitis and 1 (2.8%) periorbitary pigmentation. 4.1% (3 cases) suffered neutropenia due to medullar chemosuppression. There were no cases of severe anemia or thrombocytopenia. There were no cerebral ischemic events or mortality associated to the procedure.

CONCLUSION

IAC with melphalan and topotecan is a safe and effective treatment option for persistent or recurrent retinoblastoma, able to reduce enucleation rates.

Intraluminal shunt for the thoracic aorta: blood flow and function in chronic studies

BACKGROUND

Aortic cross-clamping during operations on the thoracic aorta may result in paraplegia or kidney failure.

METHODS

A nonshunting method of repair was compared with intraluminal shunting in two groups of young pigs: the no-shunt group, which received simple aortic cross-clamping at the ligamentum for 15 minutes; and the shunt group, which received an aortic graft with a temporary intraluminal shunt and balloon occlusion of the inferior vena cava only during shunt insertion and removal. Blood flow to the spinal cord and viscera was measured with radiolabeled microspheres on days 1, 3, 5, and 7 after operation. Renal and neurologic function and histology also were studied.

RESULTS

In the no-shunt group, there was hyperemia of the lumbar cord compared with the shunt group. There were no significant differences in renal cortex blood flow or creatinine clearance. Seven of 10 animals in the no-shunt group had paraplegia, compared with none in the shunt group. Histologic studies of the lower lumbar cord showed bilateral central necrosis of gray matter in the no-shunt group, but no evidence of necrosis in the shunt group.

CONCLUSIONS

An intraluminal shunt allowed thoracic aorta reconstruction without paraplegia.

Intraluminal shunt for the thoracic aorta: spinal cord and visceral blood flow in acute studies

Aortic cross-clamping during surgery of the thoracic aorta may result in paraplegia or kidney failure. Difficulties associated with external shunts and bypasses have limited their use. Therefore we compared intraluminal shunting to the nonshunting method of repair in neonatal pigs. Blood flow to the spinal cord and viscera was measured with radiolabeled microspheres before, during, and after thoracic aortic cross-clamping or shunting. Two no-shunt groups were studied: One group was clamped distal to the left subclavian artery for 30 minutes and the other for 1 hour. In the intraluminal shunt group, a shunt was placed in the aorta just below the ligamentum arteriosum for 1 hour; it was then removed and the aorta repaired. In the no-shunt groups, there was virtually no blood flow to the lower cord and viscera during the cross-clamp period. Hyperemia of the lower thoracic and lumbar cord occurred in the no-shunt 30-minute group 15 minutes after clamp removal. In the no-shunt 60-minute group, flow initially returned to the lumbar cord but then declined; and after 1 hour of reperfusion it was significantly lower than baseline. Renal blood flow was even more severely affected in the no-shunt 60-minute group, with minimal recovery during the reperfusion period. In the intraluminal shunt group baseline spinal cord and visceral blood flow were maintained during thoracic aortic cross-clamping, without the problems associated with extracorporeal circulation.