Treatment of Ocular Adnexal Lymphoma with Intralesional Injection of Anti-CD20 Monoclonal Antibody: Preliminary Results

Abstract

Purpose: : in this pilot study we evaluated the efficacy of intralesional anti-CD20 monoclonal antibody (Rituximab) injection in five patients affected by histologically proven ocular adnexal lymphoma (OAL).

Methods: : five consecutive patients with OAL diagnosed at the Ocular Oncology Service of Scientific Institute San Raffaele,Milan were treated with intralesional Rituximab injection as a single therapeutic agent. Two patients had monolateral conjunctival MALT lymphoma, two had monolateral conjunctival follicular lymphoma and one had follicular lymphoma of the eyelid. The treatment protocol consisted of one intralesional Rituximab injection every week for four consecutive weeks, followed by one injection every month for six consecutive months. After topical anesthesia, we slowly injected 1.5ml of undiluted Rituximab (10mg/mL) into the conjunctival lesion. We followed the patients for six months after the treatment course to evaluate its efficacy. During the treatment protocol steps and every three months during the follow-up each patient underwent complete clinical ophthalmological evaluation and slit-lamp high-resolution digital pictures of the lesion were obtained. Outcome assessments were based on the macroscopic reduction of the lesion and on the presence or absence of recurrence.

Results: : we achieved a complete clinical remission in two patients with conjunctival MALT lymphoma and in one patient with follicular lymphoma of the eyelid. Two patients with follicular lymphoma of the conjunctiva only achieved partial clinical remission. All patients completed the planned treatment without local or systemic side effects.

Conclusions: : our pilot study demonstrates that intralesional Rituximab injection is an effective single-agent therapy for OALs, with a better response for those with conjunctival MALT lymphoma and with follicular lymphoma of the eyelid than for those with conjunctival follicular lymphoma. We recognize that our short disease-free follow-up period (6 months) is a limiting factor of this study. Duration of response and potential late effects remain to be defined, and a large prospective trial to address this promising approach is warranted.

Keywords: tumors • conjunctiva