Retinal Astrocytic Hamartoma in a Child With Neurofibromatosis Type 1 Treated With Selumetinib.

Retinal astrocytic hamartoma (RAH) is a rare benign retinal tumor most commonly associated with tuberous sclerosis complex and is typically stable. RAH may also rarely occur in neurofibromatosis type 1 (NF1), an autosomal dominant disorder characterized by skin pigmentation abnormalities and multiple neurofibromas. We present a case of a child with NF1 and symptomatic, inoperable plexiform neurofibromas, for which selumetinib was initiated. Incidentally, the patient also had a progressive RAH involving the optic disc, leading to severe exudative retinal detachment. Following selumetinib therapy, the RAH showed measurable reduction in size (from 5.51 × 10.69 mm to 5.46 × 5.23 mm on ocular ultrasonography) and resolution of associated retinal detachment This case highlights a novel observation of selumetinib-associated RAH regression in an a patient with NF1. Although selumetinib was not prescribed for ocular disease, these findings suggest a potential off-target benefit and support further exploration of mitogen-activated protein kinase inhibitors in managing vision-threatening RAH in NF1.