Orbital leiomyosarcoma after radiation therapy for bilateral retinoblastoma

Leiomyosarcoma rarely occurs in the orbit and is seldom encountered as a postirradiation sarcoma in any anatomic location. Three patients with bilateral retinoblastoma who had received radiation therapy are known to have orbital leiomyosarcoma develop in their third decade of life. The clinical and pathological data pertaining to two of these patients are given and discussed herein.