Clinicopathologic features and behavior of cutaneous eyelid melanoma.

Objective: To study the clinical and histopathologic features of cutaneous eyelid melanomas and identify prognostic factors in the behavior of such tumors.

Design: Retrospective observational case series.

Participants: Twenty-three patients with cutaneous eyelid melanomas without conjunctival involvement.

Methods: Patients' charts were reviewed for clinical information, treatment procedure, and disease course (updated at the time of study). Histopathologic sections from all surgical procedures were reviewed.

Main Outcome Measures: Histologic type of melanoma, tumor growth phase, Clark's level of invasion, tumor thickness, and other microscopic features were evaluated in each case. The width of excision margins was considered and measured histologically when possible.

Results: There was no gender predilection. The lower eyelid was more frequently involved than the upper eyelid or canthi. Seventeen cases (74%) were invasive, and six (26%) were in situ melanomas. Lentigo maligna melanoma was the most common histologic type, accounting for 61% (14 cases) of all melanomas and 53% (9 cases) of invasive melanomas. Superficial spreading melanoma accounted for 22% (5 cases) and nodular melanoma for 17% (4 cases) of all melanomas. Surgical excision, as the treatment of choice, was incomplete in nine cases, two thirds of which were lentigo maligna melanoma (in situ or invasive). Tumor reappeared in 77.8% of these cases. Fourteen patients had initial narrow excisions, and three of them (21.4%) had local recurrences. Although recurrence occurred in one each of our "in situ," "thin," and "thick" melanomas, it proceeded to distant metastases and death only in the "thin" one. Adjuvant radiotherapy was used in six patients with successful disease control in two cases.

Conclusions: Eyelid skin melanomas have a relatively good clinical prognosis. The histologic type and thickness of the primary melanoma were not clearly related to the clinical behavior once they were completely excised. The use of very narrow excisions of 5 mm or less was associated with greater frequency of local recurrence. Lentigo maligna melanomas were the largest tumors at presentation and, despite being thinner, were a greater surgical challenge. This type of melanoma is almost certainly underdiagnosed by ophthalmologists.