MONDAY, Dec. 1, 2025 (HealthDay News) -- Compounded imiquimod 5 percent ointment may be safe and effective for diffuse conjunctival melanoma in situ (MIS) or ocular surface squamous neoplasia (OSSN), according to a case series study published online Nov. 26 in JAMA Ophthalmology.R. Christopher Bowen, M.D., from the Northwestern University Feinberg School of Medicine in Chicago, and colleagues examined the outcomes of compounded imiquimod 5 percent ointment for diffuse conjunctival MIS or OSSN in an interventional case series study. The case series included five patients with a histological diagnosis of conjunctival intraepithelial neoplasia (CIN), conjunctival squamous cell carcinoma, conjunctival MIS, or conjunctival melanoma with adjacent clinical primary acquired melanosis (PAM), who received compounded imiquimod ointment applied to the conjunctival surface five days a week for at least 12 weeks.The researchers observed complete clinical and histological response of CIN with moderate dysplasia, partial histological response, and no histological recurrence of positive margins of squamous cell carcinoma excision at 12 weeks of treatment. Partial clinical response of diffuse MIS with mild persistence of epithelial pigmentation at the corneal limbus at the 7-o'clock position was seen at 12 weeks of treatment; however, in the areas of initial map biopsy, there was complete histological response. Complete clinical and histological response of PAM was seen at 15 weeks of treatment. All five patients experienced ophthalmic adverse events, only affecting the ocular surface and eyelids; within one to two weeks of drug holiday or completing treatment, all ocular surface adverse events resolved."Further studies with prospective follow-up, controls, and larger numbers are needed to assess longer-term risks and benefits of this therapy," the authors write.One author disclosed ties to Elsevier.Abstract/Full Text (subscription or payment may be required)Editorial (subscription or payment may be required).Sign up for our weekly HealthDay newsletter