Impact of an active surveillance programme on outcome of patients (pts) with uveal melanoma (UM) after primary curative therapy (PTx): results of a single-institution experience

Abstract

Background: About 30% of pts withUMdevelop metastatic disease (MUM) despite PTx. Liver is by far the commonest site of metastases. MUM has poor prognosis and no systemic treatment (STx) has been proven to improve overall survival (OS). However, the role of active surveillance for metastatic disease is still controversial. Method(s): We performed an outcome analysis of allUMpts prospectively registered onto our active surveillance programme after PTx. All pts had systemic staging at initial diagnosis of UMand then 6-monthly liver imaging (CT triple-phase or 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. Result(s): Out of 166 pts registered between April 2009 and April 2017, 36 (22%) developed MUM: 14 pts relapsed<2 yrs, 17 between 2 and 5 yrs, 5 >5 yrs from PTx. MUMpts characteristics: males 19 (53%); median age 58 (range 34-85); median tumour thickness at diagnosis 9mm (2-22); sites of metastases: liver only 13 (36%), liver + other sites 21 (58%), extra-hepatic only 2 (6%). Relapses were asymptomatic and detected on surveillance imaging in 29 (80%) pts. Nine pts (7 detected from surveillance) underwent primary hepatic metastasectomy (HM), 27 (75%) pts were non-resectable (NR) and underwent STx (n=18), locoregional Tx (n=4), best supportive care (n=5). Overall, 29/36MUMpts received immunotherapy with either ipilimumab or nivolumab/pembrolizumab. At a median FU of 36.5 mos (1-103), 27 pts have died and the median OS is 16.6mos (95%CI: 7.8-25.3). Both PFS and OS were statistically significantly longer forHMpts compared to NR pts (PFS: 10.8 vs 4.4mos, p=0.01/OS: 24.9 vs 13.4mos, p=0.04). Eight out of 9 pts developed further disease relapse after HM. Conclusion(s): Our data indicate that active surveillance after PTx of UMcan allow detection of asymptomatic potentially resectable liver metastases, especially in pts with high riskUM(i.e. tumour thickness>5mm). Although durable remission after HMis rare PFS and OS may be significantly prolonged.