Advances in the management of conjunctival melanoma

Abstract

Malignant melanoma of the conjunctiva is a rare but serious condition. Over the last several years, there have been important advances in the classification, diagnosis, and treatment of this condition. Recent cytogenetic and immunohistochemical studies are increasing understanding of its tumorigenesis. Diagnosis, although still made via histopathology, has been aided with imaging techniques such as ultrasound biomicroscopy and anterior segment optical coherence tomography. Primary treatment consists of surgical excision. But adjuvant treatments with cryotherapy, topical chemotherapy, and radiation therapy have shown increased success. Sentinel lymph node biopsy has shown early promise of detecting micro-metastasis. Long term follow-up of patients with conjunctival melanoma with systemic surveillance is necessary to detect recurrences and metastases.

Keywords: conjunctival melanoma; malignant melanoma of the conjunctiva.

Figure 1

Color photograph of conjunctival melanoma. Red arrows indicate malignant melanoma arising from primary acquired melanosis. The white asterisk indicates primary acquired melanosis that was found to have severe atypia.

Figure 2

Anterior Segment OCT image of an amelanotic melanoma

Figure 3

Ultrasound biomicroscopy image of conjunctival melanoma

Figure 4

Pump-probe imaging of conjunctival melanoma 4a. Pump probe image of conjunctival melanoma demonstrating distribution of melanin components. 4b. Corresponding H&E and unstained section of lesion. (Courtesy of Warren Laboratory, Duke University)

Figure 5

Surgical excision of a limbal conjunctival melanoma. 5a. A careful corneal epitheliectomy of the corneal part of the lesion is done without disruption of Bowman's membrane. 5b. The conjunctival part of the tumor is excised with at least a 2 mm margin. 5c. After full excision, the lesion is carefully oriented on filter paper. A specified corner has been pre-tagged with a suture. 5d. After a double freeze-thaw, overlapping pattern of cryotherapy to the conjunctival margin is done, the ocular surface is reconstructed with reapposition of the conjunctiva and amniotic membrane grafting.

Figure 6

Sentinel lymph node biopsy 6a. Identifying the lymph node with γ-probe localization. 6b/c. Excision of the identified sentinel lymph node. 6d. The excised lymph node.