Abstract
OBJECTIVE: Retinoblastoma (Rb) and Langerhans cell histiocytosis (LCH) are rare and distinct diseases that can coexist in a patient. We present a case report of a 5-year-old male who was diagnosed with bilateral retinoblastoma and LCH involving the skull and spine. METHODS: The patient underwent a detailed clinical evaluation, including a complete ophthalmic examination, neuroimaging studies, and bone marrow biopsy. A genetic test confirmed the presence of the BRAF V600E mutation in the LCH lesion. Treatment with BRAF inhibitors was initiated for LCH, followed by chemotherapy and left eye enucleation for retinoblastoma. The patient was monitored closely during treatment and at follow-up visits. RESULTS: The patient responded well to therapy, with no evidence of disease recurrence at 12-month follow-up and the enucleated eye was replaced with a prosthesis. The BRAF inhibitor was found to be an effective therapeutic option for the patient with BRAF-positive LCH. CONCLUSION: Our case highlights the importance of early diagnosis and prompt treatment in managing complex cases with coexisting retinoblastoma and LCH. Treatment with BRAF inhibitors could be a promising therapeutic option for patients with BRAF-positive LCH. Further studies are needed to evaluate the efficacy and safety of BRAF inhibitors in the treatment of LCH. The long-term outcome and potential late effects of combined therapy for coexisting retinoblastoma and LCH should also be monitored closely.