The 23-year-old has admitted he is attracted to the possibility of playing in England should Palace firm up their interest.
“In Bergamo I feel great, I have never hidden that," Castagne told Gazzetta dello Sport.
“Now we are negotiating a contract renewal and I think it was right to start talking about it once the season had ended. I am calm, we will see what the owners' plans will be.
“Serie A is a very competitive legue, I like it, but one day I would like to compete in the Premier League.
“As for the offers, I will be honest, in general there isn't a lack of them, but the priority is Atalanta."