The Ligue 1 Champions signed the Brazil international from Sao Paulo at the start of the 2012/13 season before the playmaker joined up with his new team-mates six months later.
Lucas has scored five goals for PSG – all of which came last season – and the midfielder has also played a role in helping the squad to win back-to-back Ligue 1 titles.
Although the club’s owners see the 21-year-old as a key player for the future, recent reports have linked Lucas with a move away from Ligue 1 as PSG step up their attempts to bring Chelsea midfielder Eden Hazard back to France.
It is thought PSG could be ready to cash in on Lucas in order to finance a big-money move for the Belgium international this summer and balance the books after agreeing a €60 million deal for Blues defender David Luiz.
However, the Brazilian, who was left out of the Selecao's World Cup squad, has insisted that despite rumours of his departure, he is content with life at PSG.
"I did not always play this season, but I've been in big games and I scored decisive goals. We won three titles and I consider myself to be fully involved [in the team],” he told Le Parisien.
“I am part of this adventure in this fantastic club with an ambitious generation. I am very happy at Paris.”
He added: "We're starting to see more and more kids with the PSG jersey. The reputation of the club has crossed the Atlantic and Paris will soon reap the benefits.
“With all the work and investment of our leaders, PSG will become one of the best clubs in the world.”