Ocular surface squamous neoplasia: outcomes following primary excision with 2 mm margin and cryotherapy

Purpose To assess margins and the rate of local recurrence of ocular surface squamous neoplasia after excision with a 2 mm margin and cryotherapy at a single ophthalmic oncology center. Outcome measures (1) Conjunctival margin were assessed as positive, negative, or indeterminate margins. (2) Feasibility of repair without a graft. (3) Local recurrence. Methods Retrospective chart review of histologically proven conjunctival intraepithelial neoplasia and invasive squamous cell carcinoma cases that underwent excision with a 2 mm margin and cryotherapy. Results Eighty cases met inclusion criteria for the quantitative analysis. The margin was positive in six cases (7.5%), four of which were treated with post-op topical immunotherapy/chemotherapy. Of the six positive margin cases, there was one recurrence which occurred in the patient who did not receive post-op topical adjuvant therapy, however resolved after starting topical treatment. Conjunctival repair without use of a graft was feasible in 74 (93%) cases with a mean basal diameter of 6.4 mm. Total number of local recurrence was seen in three cases (4%), which were successfully treated with adjuvant topical treatment (one positive margin case, one indeterminate margin case) or repeat resection followed by episcleral plaque brachytherapy (one negative margin case). Conclusion Excision with 2 mm margin of OSSN is not associated with high rates of positive surgical margins. Even those with positive margins, when treated with adjuvant topical therapy did not develop recurrence. While achieving low rates of local recurrence, the conjunctiva is conserved, thereby minimizing the need for amniotic membrane or free conjunctival grafts for conjunctival repair.