Evaluation of interferon alpha 2b as adjunctive therapy for conjunctival melanoma

Abstract

Purpose Interferon alpha 2b (IFN-α2b) has been used as an adjunctive agent to treat conjunctival melanoma (CM), however its efficacy is unproved due to a paucity of data. We present 5 cases of incompletely excised CM lesions to inform clinical decision making regarding the adjunctive use of IFN-α2b. Observations We identified all biopsy proven CM cases treated between 1997 and 2017 at the University of Iowa. Of these, we analyzed cases in which topical IFN-α2b drops were prescribed after the initial excision to treat surgical margins that were positive for primary acquired melanosis [PAM] with or without atypia or invasive CM. We noted the origin of CM (nevus, PAM, or de novo), presence and location of margins positive for residual melanoma, duration of IFN-α2b treatment, recurrences, time to recurrence, and outcome at last follow-up. Topical IFN-α2b drops (1 million IU/mL 4 times daily for 3–6 months) were used as adjunctive therapy in 5 cases following incomplete surgical excision of CM. The preceding lesion was PAM in 4 cases and compound nevus in 1 case. In 2 cases, margins were positive for PAM with atypia and both resulted in remission of melanoma at 54 and 33 months, respectively. However, in 3 cases, margins were positive for invasive melanoma and all 3 developed recurrence of melanoma despite IFN-α2b use. Conclusions and Importance There are limited data regarding the efficacy of IFN-α2b as adjunctive therapy for incomplete excision of CM lesions. In this series, adjunctive topical IFN-α2b did not prevent recurrence in cases with surgical margins positive for invasive melanoma. Our results indicate that caution should be exercised when considering adjunctive IFN-α2b to treat CM lesions not excised completely.

Management Issues in Conjunctival Tumours: Conjunctival Melanoma and Primary Acquired Melanosis

“…Evidence for the use of topical interferon-α2b (IFN-α2b) and 5-fluorouracil, which are commonly applied in the management of ocular surface squamous neoplasia, is limited. Topical IFN-α2b has been used as an adjuvant after surgical resection and cryotherapy with or without positive histopathological margins, if patients have been intolerant to, or failed, topical MMC [46–48]. However, the case series are small and the indications for its use vary.…”

Structural Protein Analysis of Driver Gene Mutations in Conjunctival Melanoma

“…Wide excision with a "no touch technique" in combination with cryotherapy is the modern approach for managing CM [1,[6][7][8][9][10][11]. Limitations of this technique include the concern for extensive insult to the ocular surface with excisional biopsy and the potential for residual neoplastic cells.…”

“…Limitations of this technique include the concern for extensive insult to the ocular surface with excisional biopsy and the potential for residual neoplastic cells. To help reduce the rates of recurrence, most surgeons will add adjuvant brachytherapy and/or topical chemotherapy (mitomycin C, topical interferon alpha 2b) to the primary excision with cryotherapy [1,[6][7][8][9][10][11][12][13][14][15][16][17]. Despite the use of adjuvant therapies, the cumulative rates of local recurrence at 10 years are 36.9% (CI: 26.5-49.9%) [6].…”

Current Management of Conjunctival Melanoma Part 2: Treatment and Future Directions

“…In addition, at the immunohistochemical level, CMs and to a certain extent PAM, express NAD(P)H:quinone oxidoreductase, which promotes bioactivation of mitomycin C. 21 Table 1 lists the studies in which mitomycin C was used as primary or adjuvant treatment for CM. 5 , 16 , 17 , 18 , 19 …”

“…A review of the literature involving topical IFN-α2b eye drops for CM is summarized in Table 1 . 5 , 16 , 17 , 18 , 19 …”