An audit of conjunctival melanoma treatment in Liverpool

Abstract

Purpose To evaluate treatment of conjunctival melanomas at the Ocular Oncology Service in Liverpool. Methods We included 40 patients initially treated at our centre for invasive conjunctival melanoma and 36 patients referred for salvage therapy after surgery elsewhere. Patients underwent local excision or radiotherapy. Adjunctive cryotherapy for invasive and intra-epithelial neoplasia was abandoned in favour of ruthenium brachytherapy and mitomycin C chemotherapy, respectively. Tumours were staged according to circumferential spread, basal diameter, and histological thickness. Results The 40 previously-untreated tumours were confined to bulbar conjunctiva in 31 patients and involved extrabulbar conjunctiva in 9, affecting caruncle in 6 of these. All eyes were conserved, most retaining initial visual acuity. Invasive conjunctival recurrence, which occurred in six patients, was more likely with medial tumours (Log-rank, P ¼ 0.004) and if treatment did not include radiotherapy (Logrank, P ¼ 0.03). Four patients died of metastases, all with caruncular involvement. Of the 36 patients referred for salvage therapy after previous surgery, 11 had no visible tumour, 9 had only intra-epithelial neoplasia, and 16 had invasive melanoma, which was recurrent in seven. After salvage therapy, five patients died, all of whom were referred with recurrent invasive tumour and only one of whom had caruncular involvement. Conclusions Excision of invasive melanoma with adjunctive brachytherapy and topical chemotherapy achieved high rates of local tumour control with little ocular morbidity. Without caruncular involvement, diseasespecific mortality was rare unless the patient was referred after a surgical procedure. Our results suggest that inadequate surgical intervention increases risks of local recurrence and metastatic death.

Conjunctival melanoma and melanocytic intra-epithelial neoplasia

“…The brachytherapy is administered even if histology suggests complete surgical clearance, as conventional sectioning may have missed the deepest part of the tumour. If the tumour involves the fornix or caruncular area, then we administer proton-beam radiotherapy 5 (Figure 8).…”

“…5,27 Local tumour recurrence is reported to occur in more than 50% of these cases. 23,38,39 Risk factors for recurrence are reported to be: multifocal disease, non-limbal position of the tumour, involvement of the surgical margin, and surgical excision without adjunctive treatment.…”

“…5 Our surgical approach has been described previously 5 ( Figure 7). First, the conjunctival incision lines are marked on the conjunctiva with bipolar diathermy, which also prevents haemorrhage.…”

“…This has enabled audits, which indicate that medial tumours, especially those involving the caruncle, carry a relatively poor prognosis. 5 We have also devised a system for histological scoring for conjunctival melanocytic intraepithelial neoplasia (C-MIN), which in our institution has replaced the term primary acquired melanosis (PAM) with varying (subjectively evaluated) degrees of atypia. 4 Our data have contributed to the development of the 7th edition of the tumour-nodemetastasis (TNM) staging systemic compiled by the American Joint Committee on Cancer (AJCC).…”

“…1,4 Furthermore, our understanding of the biology of these neoplasms is hampered by a lack of adequate correlation between clinical, histological, and genetic features of the disease. 5 We have developed methods for clinical mapping of conjunctival tumours 6 (Figure 1). This has enabled audits, which indicate that medial tumours, especially those involving the caruncle, carry a relatively poor prognosis.…”