Retrograde metastasis of cutaneous melanoma to conjunctival lymphatics.

Report of a Case. A 61-year-old man developed cutaneous melanoma in the right preauricular skin. It was managed by surgical resections, skin grafts, irradiation, chemotherapy, and laser for local recurrences and cervical node metastasis. After 18 months, he was referred for progressive ipsilateral conjunctival pigmentation. Examination disclosed cutaneous pigmentation and scarring in the right preauricular area (Figure 1A). The ipsilateral conjunctiva showed a peculiar widespread linear network of pigment (Figure 1B and C). The branching pattern was suggestive of lymphatic infiltration, and nearby conjunctival blood vessels were normal. Our clinical diagnosis was retrograde spread of cutaneous melanoma to conjunctival lymphatics. Histopathologic analysis of a conjunctival biopsy disclosed epithelioid melanoma cells within lumina of dilated channels lined by endothelial cells, consistent with lymphatics (Figure 2A). Adjacent blood vessels contained erythrocytes but no tumor cells. The overlying conjunctival epithelium was normal without junctional activity. Immunohistochemically, the endothelium of the tumor-containing vessels was reactive to monoclonal antibody D2-40, a specific marker for lymphatic endothelial cells. In contrast, the adjacent nontumor-containing blood vessels stained positive for CD34 and negative for D2-40 (Figure 2B and C). The histopathologic diagnosis was retrograde conjunctival intralymphatic metastasis from cutaneous melanoma. The patient was treated with an iodine I 125 plaque delivering 60 Gy to the entire conjunctiva over 7 days. Despite a favorable local response to irradiation, the patient died of disseminated melanoma after 16 months.