Photodynamic therapy with verteporfin to induce regression of aggressive retinal astrocytomas

Purpose: To evaluate the effect of photodynamic therapy (PDT) with verteporfin on symptomatic, aggressive retinal astrocytomas. Methods: A prospective, interventional study in a tertiary referral centre. Two patients were treated with a single session of PDT using the standard parameters of the Verteporfin in Photodynamic Therapy (VIP) study: a 34-year-old man whose previously stationary juxtapapillary retinal astrocytoma, secondary to tuberous sclerosis, progressed within 7 months to involve the foveola; and a 68-year-old man whose acquired retinal astrocytoma progressed over 18 months in spite of standard photocoagulation. Both tumours were vascularized and had caused secondary lipid exudation and an exudative retinal detachment. Outcome measures were visual acuity, resorption of subretinal fluid, tumour height and fluorescein angiography. Results: The progressing, vascularized part of both retinal astrocytomas regressed, with little change in the poorly vascularized, stationary part of the congenital hamartoma. Visual acuity improved in the first patient and was unchanged in the second by 3 months, with stable vision in both and no sign of recurrence at 2 years. The exudative retinal detachments resolved completely. Tumour height reduced a median of 30%. Regression was associated with obliteration of tumour vessels within the progressing part of the lesion, with closure of some of the dilated retinal capillaries over the tumour. Intraretinal microvascular abnormalities and scattered haemorrhages appeared outside the treated area in the first patient. Conclusion: PDT with verteporfin can induce regression of progressive, vascularized, aggressive retinal astrocytomas and may prevent typical progression to total retinal detachment and enucleation, whether the astrocytoma is associated with tuberous sclerosis or not. PDT may be considered a first-line treatment for aggressive retinal astrocytomas.