About 30% of pts with UM develop metastatic disease (MUM) despite PTx. MUM has poor prognosis and no systemic treatment (STx) has been proven to improve overall survival (OS). The role of active surveillance after PTx is still controversial.
We performed an outcome analysis of all UM pts prospectively registered onto our active surveillance programme after PTx. All pts had systemic staging at diagnosis and then 6-monthly liver imaging (CT triple-phase, MRI, ultrasound) and clinical review for the first 5 years and 12-monthly afterwards. Progression-free survival (PFS) was calculated from time of first systemic relapse to first disease progression, OS from time of first systemic relapse to death or latest FU.
Out of 169 pts registered between April 2008 and April 2018, 32 (19%) developed MUM during surveillance: 14 pts (44%) relapsed <2 yrs, 14 (44%) >2 and <5 yrs, 4 (12%) >5 yrs from PTx. Median FU is 46.8 mos. MUM pts characteristics: males 17 (53%); median age 59yrs (range 31-86); median tumour thickness at diagnosis 9mm (range 3-22); sites of metastases: liver only 10 (31%), liver + other sites 19 (60%), extra-hepatic only 3 (9%). Relapses were asymptomatic and detected on surveillance imaging in 25 (78%) pts. Median duration to relapse after PTx is 27.4 mos. Eight pts (25%) were upfront resectable (PRx) and underwent radical hepatic metastasectomies, 24 pts (75%) were non-resectable (NRx) and underwent immunotherapy (n = 12), other systemic therapies (n = 5) [4 chemotherapy, 1 BRAF inhibitor], locoregional Tx (n = 3) [2 Delcath, 1 RFA], best supportive care (n = 4). At median FU of 46.8 mos (0-120 mos), 27 pts have died and the median OS is 13.5mos. PFS was longer in PRx pts compared to NRx pts (PFS: 9.8 vs 4.4 mos / OS: 20.7 vs 39.3 mos). All 8 resectable pts developed further disease relapse [median time to hepatic relapse 9.8 mons (range 5.2 -13.1)].
Our data indicate that active surveillance after PTx of UM can allow detection of asymptomatic potentially resectable liver metastases, especially in pts with high risk UM (i.e. thickness >5mm). Although durable remission after hepatic metastasectomy is rare, PFS and OS may be meaningfully prolonged.
Clinical trial identification
Legal entity responsible for the study
St Vincents' Hospitals, Dublin, Ireland.
Has not received any funding.
All authors have declared no conflicts of interest.