Primary intraocular lymphoma (PIOL) is a subtype of primary central nervous system lymphoma, and is usually a diffuse, large B-cell non-Hodgkin's lymphoma in which malignant lymphoid cells invade the vitreous body, retina, or optic nerve head. The most common symptoms are floaters and blurred vision. It can masquerade as chronic uveitis or vitritis. When uveitis presents with unknown origin in elderly patients, or is refractory to steroid treatment, IOL should be considered.
Systemic chemotherapy, such as intravenous injections of high doses of methotrexate (MTX) or radiation therapy, or both, was formerly the standard treatment for PIOL. However, systemic chemotherapy can cause delayed neurotoxic effects, and an intravitreal injection of lower concentrations of chemotherapy agents after intravenous MTX may facilliate persistent PIOL. Orbital radiation can often lead to a prolonged disease-free state, but ocular recurrences can occur, and many side effects such as radiation retinopathy, optic neuropathy, and dry eye syndrome can develop. In addition, orbital radiation cannot be repeated if PIOL recurs.
In the late 1990s, intravitreal injection of MTX was suggested and has been used as an alternative local therapy for PIOL. It is also efficacious in obtaining ocular remission without serious adverse events in most (91 percent) patients, and is repeatable for recurrent cases.
In order to prevent central nervous system (CNS) involvement and improve the PIOL, we prospectively evaluated the efficacy of combined therapy using intravitreal MTX and systemic high-dose MTX on treatment-PIOL.
Patients with diagnosed PIOL were recruited between April 2014 and February 2017. Eleven patients were enrolled in this study, including four men and seven women, with a median age of 69 years (27-88 years).
The registration pace was 4 in 2014, 3 in 2015, and 4 in 2016, achieving the initial 2-3 cases per year, but there were no registered patients since 2017.
Sufficient cases were not collected for evaluation, and it had to be canceled.
We prospectively evaluated the efficacy of combined therapy using intravitreal MTX and systemic high-dose MTX in 11 patients with confirmed diagnosis of PIOL. During treatment with intravitreal MTX injection, no patients experienced adverse event after the injection.
The patient was recruited unsuccessfully, treatment was interrupted frequently, and the study was discontinued.