Objective: To investigate the feasibility and safety of preoperative lymphoscintigraphy and sentinel lymph node (SLN) biopsy for conjunctival melanoma.
Methods: A 49-year-old man with a biopsy-proven malignant melanoma of the conjunctiva (caruncle) underwent preoperative lymphoscintigraphy and SLN biopsy using a technique in which both isosulfan blue dye and technetium Tc 99 m sulfur colloid were injected in the subconjunctival space around the primary lesion. The conjunctival melanoma was excised just before identification and removal of the SLNs. The SLNs were excised along with concomitant dissection of their associated lymph node basins. The SLNs were evaluated histologically using serial sectioning and immunohistochemical staining with antisera against the S-100 protein and the melanoma antigen HMB-45.
Results: Three SLNs were identified in the left submandibular and the left upper and middle jugular lymph node basins during the preoperative lymphoscintigraphy. The same three SLNs were successfully identified in the operating room. The SLNs were histologically negative, and the immunohistochemical staining against S-100 and HMB-45 was also negative. We did not observe any immediate adverse effects on the globe or the periocular structures from lymphatic mapping and SLN biopsy. By 24 hours after injection of blue dye, only a faint trace of blue was visible on the ocular surface.
Conclusions: Preoperative lymphoscintigraphy and SLN biopsy can be performed safely in patients with conjunctival melanoma. A larger study is planned to determine the sensitivity of this technique for the detection of occult regional nodal disease in patients with conjunctival melanoma.