Intravitreal chemotherapy for the treatment of recurrent intraocular lymphoma

Aim-To develop and assess a protocol for the treatment of intraocular lymph oma by intravitreal injection of methotrexate and thiotepa. Methods-A patient with intraocular non-Hodgkin's lymphoma which recurred af ter radiotherapy and repeated systemic chemotherapeutic regimens underwent repeated intravitreal injections of methotrexate and thiotepa. The patient was closely monitored by cytology, anterior chamber flare measurements, IL- 10 and IL-6 levels. Methotrexate drug clearance studies were performed on v itreous samples taken before each injection. Results-Complete tumour clearance was achieved by the third week of therapy . IL-10 and IL-6 levels quickly dropped to barely detectable levels as the tumour was cleared from the eye. Flare measurements decreased from 500 to 1 5 photons/s over the same time. A plot of the methotrexate levels over time revealed a first order kinetic rate of elimination with an effective tumor icidal intravitreal dose persisting for 5 days after injection. Conclusion-Intravitreal chemotherapy for the treatment of recurrent intraoc ular lymphoma appears effective in prolonging local remission of ocular dis ease even in the presence of an aggressively growing tumour. A single intra vitreal injection of methotrexate can lead to a prolonged tumoricidal conce ntration lasting for a longer period than that achieved by systemic adminis tration.