Abstract 5749
Background
Metastatic primary UM (MUM) is a rare cancer with a poor prognosis and a median overall survival (OS) of about 6 months in historical datasets. Despite the significant improvements produced by ICPIs in metastatic cutaneous melanoma, pts with MUM have been excluded from most trials of ICPIs thus causing an almost complete lack of prospective clinical data.
Methods
An analysis of all pts with MUM included in our institutional prospectively accrued database of all primary UM pts. OS was calculated from date of first diagnosis of metastatic disease to date of death or last follow up.
Results
Out of 169 pts registered between April 2008 and April 2018, 39 pts had MUM. Pts characteristics: males 20 (51%), median age 63 years (range 34-85), median tumour thickness at diagnosis 9mm (range 2-22), tumour location: choroidal 19 (49%) ciliochoroidal 8 (20%), undefined/unknown 12 (31%). Primary therapy (PTx): enucleation 22 (56%), brachytherapy 15 (38%), both 2 (5%). Sites of metastases: liver only 29 (74%), liver + other sites 7 (18%), extra-hepatic only 3 (8%). Median follow-up is 37.9mos. 11 pts had resectable disease at diagnosis and underwent primary metastatectomies, 28 patients underwent: immunotherapy (15), other systemic therapies (5), locoregional Tx (3), best supportive care (5). Median OS is 14.25 mos. At the database lock-out (April 30th 2018), 27 pts (70%) have died of MUM. Pts without hepatic involvement tend to have longer median OS (25.9mos) vs those with liver only disease (16.6mos) or liver + other sites (OS 8.9 mos). Overall, 32/39 pts (82%) received ICPIs during the course of their disease: ipilimumab 13 (40%), single agent anti-PD1 5 (16%), sequential/concomitant ipilimumab and anti-PD1 14 (44%). Median OS is 23.7 mos (sequential Ipilimumab and anti-PD1) vs and single-agent ipilimumab (13.8mos) vs single-agent PD-1 (14.7mos).
Conclusions
In our single-institution experience of nonresectable MUM pts, sequential/concomitant ICPIs produced a longer median OS than single-agent ipilimumab or anti-PD1 and should be considered the preferred treatment option. A more indolent disease could have contributed to more prolonged OS in a subgroup of pts without hepatic involvement.
Clinical trial identification
Legal entity responsible for the study
St Vincents' Hospitals, Dublin, Ireland.
Funding
Has not received any funding.
Editorial Acknowledgement
Disclosure
All authors have declared no conflicts of interest.