Complete reversal of bilateral optic nerve infiltration from lymphoblastic leukemia using chemotherapy without adjuvant radiotherapy.

Background: Leukemic involvement of the eyes is rare, therefore, treatment relies on previous case reports. The treatment of ocular complications poses additional difficulties, because the eye is considered as a pharmacological "sanctuary" for patients with acute lymphoblastic leukemia (ALL). Therefore, radiotherapy is the main therapeutic choice; however, it might lead to many important side effects. To the best of our knowledge, this is the first case report of a bilateral leukemic optic nerve infiltration that remitted with chemotherapy without adjuvant radiotherapy.

Case Presentation: A 30-year-old female patient with previous history of remitted ALL presented with a one-week history of floaters in her right eye. Her ophthalmological exam showed remarkable optic disc swelling, in both eyes. She was diagnosed with ALL relapse presenting as a bilateral optic nerve leukemic infiltration. Local radiotherapy was planned for both eyes, however, due to efficient recovery with chemotherapy, it was cancelled. Allogenic bone marrow transplantation was subsequently performed. The patient is being followed up and ALL remitted.

Conclusion: Leukemia relapse on central nervous system, despite rare, is a sign of poor prognosis and requires prompt treatment. Its occurrence on ocular tissues is even rarer. It is hypothesized that the blood-brain barrier limits the delivery of chemotherapeutic drugs to the eye and infiltration of the optic nerve by leukemic cells might prejudice the flow of cerebrospinal fluid between the cranial space and the optic disc.