Botryoid Rhabdomyosarcoma of the Conjunctiva in a Young Boy.

Primary conjunctival rhabdomyosarcoma (RMS) is a rare entity that can present with or without papillomatous features. A 5-year-old Asian boy was referred for a rapidly growing conjunctival tumor in the superior fornix of the left eye. Surgical excision yielded a 28 mm multilobulated papillomatous specimen that exhibited histopathologic and immunohistochemical features consistent with embryonal (botryoid) RMS. Molecular analysis revealed the absence of the PAX3/FOXO1 fusion gene, indicating favorable prognosis. After surgery, he was promptly treated with systemic chemotherapy and proton beam radiotherapy.