Conjunctival Tumors: Pharmacotherapy

Medical therapy for ocular malignancies is an expanding field with increasing options for ocular surface malignancies. Epithelial, lymphoproliferative, and pigmented lesions of the conjunctiva now all have pharmacologic therapeutic options at the clinician’s disposal. Topical chemotherapy drops of interferon alpha-2b (IFNα-2b), 5-fluorouracil (5-FU), and mitomycin C (MMC) have shown promising results as a primary therapy for ocular surface squamous neoplasia (OSSN). They have also been used as adjuvants to surgical excision. While these agents are the main medical agents for OSSN, retinoic acid, aloe vera, cidofovir, and anti-vascular endothelial growth factor have been tried with some success in small cohorts. Pharmacological therapy for ocular and adnexal lymphoma is dependent on whether the disease is localized (unilateral or bilateral) or systemic. Local therapy has traditionally been radiotherapy, but local injections of rituximab and interferon have shown some success in small series. Systemic disease is treated with systemic chemotherapies, including monoclonal antibodies and radio-tagged monoclonal agents. Conjunctival melanomas are life-threatening, and surgery remains the mainstay of treatment. In cases of unresectable disease, and as adjuvants, medical therapies are needed. Mitomycin C has an effect on pigmented cells. While imperfect, it reduces ocular surface pigmentation and atypia. The use of IFNα-2b has been reported with less success and only limited series. Novel checkpoint inhibitors targeting programmed cell death 1 (PD-1), such as pembrolizumab, have shown early potential for pigmented lesions of the ocular surface, and additional data is needed to elucidate their role in conjunctival melanoma.