The 22-year-old moved to White Hart Lane on the back of goal-laden spells at Almere City and AZ Alkmaar.
His one season in the Eredivisie saw him net 27 times in the Dutch top-flight and on 31 occasions in all competitions.
Those efforts were enough to earn senior international recognition, with the target found four times in nine appearances for the Netherlands.
Janssen has, however, struggled to reproduce that form in England, with the Premier League proving to be a tough nut to crack.
He has just three goals for Spurs in 23 outings, with his solitary strike in the league coming from the penalty spot in a 1-1 draw with Leicester.
His difficulties have sparked talk of a possible move during the January transfer window, with Galatasaray making a formal bid.
Janssen’s agent has, however, sought to distance his client from the exit talk by reiterating his determination to prove his worth with Spurs.
Patrick van Diermen told Omroep Brabant: “He decided to turn down all interest.
“Galatasaray came with an offer but Vincent will stay with Tottenham Hotspur. He decided to turn down Galatasaray.
“Vincent chose Tottenham Hotspur in the summer fully aware of what his chances would be to play.
“He signed a long-term contract with a good club with fantastic facilities and a good coach.
“Before he got injured he got playing time every week. He is enjoying his time and wants to fight for his chance.”
Part of the problem for Janssen is that his direct competition for a starting berth at Spurs is Harry Kane, with the England international having already netted 15 times this season.