Abstract
BACKGROUND: Mucoepidermoid carcinoma of the conjunctiva is a rare, aggressive variant of squamous cell carcinoma, with limited reports of systemic metastasis. CASE PRESENTATION: An 86-year-old man presented with a suspicious conjunctival lesion. Initial biopsy was inconclusive, but excision confirmed moderately differentiated mucoepidermoid carcinoma. Despite treatment, the tumor showed rapid orbital invasion. Imaging later revealed bilateral lung and liver metastases. Cytology confirmed metastatic spread. The patient died two months later. DISCUSSION: Mucoepidermoid carcinoma of the conjunctiva is an uncommon and particularly aggressive variant of ocular surface squamous neoplasia, often underdiagnosed due to its mixed histological components. Compared with classic squamous cell carcinoma, it demonstrates higher rates of local recurrence, deeper orbital invasion, and a greater potential for regional spread. Although distant metastasis is exceedingly rare, our case illustrates that this subtype may disseminate rapidly and extensively despite early intervention. These findings highlight the importance of performing deep biopsies to avoid sampling error, ensuring complete histopathological assessment, and considering early systemic imaging when tumor behavior appears unusually aggressive. CONCLUSION: Conjunctival mucoepidermoid carcinoma may exhibit aggressive local and systemic behavior. Early deep biopsy, complete histological analysis, and systemic imaging are essential to guide appropriate management and detect rare but fatal metastases.