It has been a very worrisome time for Dmitri Hvorostovsky. The baritone, who has been battling illness, has now pulled out of his upcoming Dublin concerts “due to a change in the schedule of his cancer treatments.”

The concert was originally scheduled for April 29, 2017, and was among just a few performances that the Russian star was giving after having pulled out of all opera engagements for the foreseeable future.

He is still slated to perform in a hotly anticipated concert alongside his close friend Anna Netrebko and her husband Yusif Eyvazov.

Hvorostovsky was first diagnosed with a  brain tumor in the summer of 2015. Despite getting medical treatment, he continued performing and made a massive comeback at the Metropolitan Opera in a production of Verdi’s “Il Trovatore.” However, in late September 2016, the singer was forced to withdraw from scheduled performances in Verdi’s “Simon Boccanegra” at the Vienna State Opera and in December 2016, he canceled his planned debut performances of Verdi’s “Don Carlo” at Moscow’s Bolshoi Theater.

He then went on to cancel all opera engagements for the foreseeable future. Despite that, some opera companies, such as the Teatro Liceu, noted that the baritone would be performing during the 2017-18 season.