High-risk uveal melanoma: A prospective study evaluating the role of magnetic resonance imaging of the liver.

Abstract

8564 Background: Almost 50% of uveal melanomas are fatal. Metastatic death occurs almost exclusively with tumours showing chromosome 3 loss and 8q gain. Metastases, which almost always involve the liver, are resectable in some patients. They are rarely detectable when the patient presents with the primary ocular tumour. Screening is therefore necessary, but there is no consensus as to who should be screened, how often, and for how long. Methods: Uveal melanoma patients with ECOG performance status 0-2 were eligible if their risk of metastatic death at 5 years exceeded 50%. Survival probability was estimated by multivariate analysis of tumour stage, histological grade and genetic tumour type. Patients underwent screening 6monthly, clinical examination, non-contrast liver MRI and liver function tests for at least five years. Results: Between Jan 2000 and November 2010, 279 high-risk patients were referred for screening. Of these, 188 (84 male, 104 female) accepted screening and underwent as least 1 MRI. The median age was 63 years (IQR 16.5). Median basal tumour diameter was 16.5mm (IQR 5.25). Chromosome 3 loss was detected in 175 tumours. Median follow up time was 28.8 months (IQR 29.1). Median relapse-free survival was 33 months (95% CI 28-38) with a 35% relapse-free survival at 5 years. After a median of 18 months (IQR 20), screening detected metastases in 90/188 (48%), 83 of whom were asymptomatic. 12 patients underwent R0 liver resection, which increased the median survival from 10 (95% CI 8.1 - 11.9) to 24 (95% CI 20.2- 27.8) months. The screening programme stimulated a UK NCRI portfolio of clinical trials in which 23 of these patients were subsequently treated. Conclusions: Six-monthly liver MRI detects metastases from uveal melanoma at an early stage, thereby enhancing opportunities for surgical metastatectomy, clinical trial participation and prolonging life.