Prognostic factors in primary malignant melanoma of the conjunctiva: a clinicopathological study of 256 cases.

Abstract

A series of 256 consecutive cases of invasive primary conjunctival malignant melanomas was examined to identify clinical and histopathological prognostic factors. The follow up period varied between 0*3 and 45 9 years (mean 9 years, median 6*3 years). The 5 year survival rate was estimated at 82.9%, the 10 year survival rate at 69.3%. Multiple regression analysis with the Cox proportional hazards model was used to assess sex, age, and a number of baseline features of conjunctival malignant melanoma as possible prognostic factors influencing melanoma related mortality. In assessing each potential prognostic factor, the effects of all other factors were taken into account in the modelling process. Tumours in unfavourable locations -that is, those involving the palpebral conjunctiva, fornices, plica, caruncle, and lid margins, were associated with 2*2 times higher mortality compared with (epi)bulbar melanomas. Patients with mixed cell type tumours had about three times higher mortality compared with those with pure spindle cell melanomas, and histological evidence of lymphatic invasion by tumour cells was also a prognostic feature, carrying a fourfold increase in the death rate. Multifocal tumours were associated with a fivefold increase in mortality among those with tumours in favourable (epi)bulbar locations, but were not prognostic in patients with melanomas in unfavourable sites. The death rate was significantly higher in those with initial tumour thickness of more than 4 mm, but only among patients with unfavourably located melanomas. Sex, age, and clinical origin of the tumour (primary acquired melanosis, pre-existing naevus, or de novo) were not useful prognostic indicators in this study. (BrJ Ophthalmol 1994; 78: 252-259)

Conjunctival melanoma and melanocytic intra-epithelial neoplasia

“…40 The estimated 5-years mortality of CoM is 12-19%, whereas the 10-years mortality rate is B30%. 1,23,25,27,42 Genetic abnormalities of CoM CoMs show mutation of BRAF (7q34). 45,46,[49][50][51][52]55 This gene encodes a serine/threonine kinase in the 45 We now test all CoMs routinely for the BRAF V600E mutation, which may predict responsiveness to Vemurafenib should the patient develop metastatic disease.…”

“…8,27,39,41 Clinical risk factors include: disease recurrence, involvement of non-bulbar conjunctiva, medial bulbar conjunctiva, caruncle and plica semilunaris, and tumour thickness of more than 2 mm. 23,27,30,35,39,42 Clinically, CoMs are staged according to the 7th edition of TNM system developed by the AJCC and the International Union for Cancer Control (UICC). 7 Poor prognostic histopathological features comprise high mitotic count, presence of epithelioid cells, diffuse intraepithelial disease, extravascular matrix pattern, lymphatic invasion/microvascular density, lymphocytic/macrophage infiltration, and surface ulceration.…”

Malignant Melanoma of the Conjunctiva

“…Patients with multifocal tumors, orbital invasion, recurrent disease, and involvement of the caruncle, plica semilunaris, eyelid margins, and the palpebral and forniceal conjunctiva have a worse prognosis for survival. 1,5,16,[53][54][55][56][57] The mortality rate has been shown to be approximately equal in patients with conjunctival melanoma in association with and without PAM with atypia. 13,16 Histopathologic findings associated with a poor prognosis include a tumor thickness of greater than 0.8 mm (in contrast to 1.5 mm or 2 mm in different studies) and involvement of the surgical margin.…”

“…1,5,16,[53][54][55][56][57] Prognostic factors include clinical features, with tumor location and extent being of major importance. Patients with multifocal tumors, orbital invasion, recurrent disease, and involvement of the caruncle, plica semilunaris, eyelid margins, and the palpebral and forniceal conjunctiva have a worse prognosis for survival.…”

“…1 It is identified most frequently in the perilimbal interpalpebral bulbar conjunctiva with tumors located in the palpebral or fornical conjunctiva or caruncle, plica semilunaris or eyelid margins having a worse prognosis for survival. 1,5 Conjunctival melanoma has no sexual predilection, and it is found predominately in middle-aged …”