An autopsied case with orbital infiltration of leukemic cells after optic nerve invasion by acute T-cell leukemia

Purpose: To report a case of T-cell acute lymphoblastic leukemia (T-ALL) with optic nerve and orbital invasion. Case: A 46-year-old man was diagnosed as T-ALL in 2014, received chemotherapy, and obtained complete remission (CR). T-ALL relapsed with blurring vision of right eye 7months after diagnosis. He lost vision in the right eye due to central retinal artery occlusion. 2nd CR was achieved, then peripheral blood stem cell transfusion (PBSCT) was operated. However 2nd relapse was detected in meninges only 3 months after the PBSCT, presenting paropsia of left eye was progressed to proptosis and ophthalmalgia. Orbital MRI scan showed contrast enhancement in bilateral extraocular muscle, left orbital fat, and left optic nerve. After treatment, proptosis was regressed transiently. Despite he died by disease progress 19 months after diagnosis. Findings: Autopsy revealed systemic T-ALL involvement including eyeball and orbit. The immunostaining pattern was positive for CD3, MIC2, negative for CD20. Coagulation necrosis of optic nerve and involvement of T-ALL in orbital fat, uvea, retina and extraocular muscle were observed. Conclusion: An autopsy report indicating involvement of orbital mass with T-ALL is extremely rare, and regarded as worthy information.