The 17-cap Holland international joined Spurs in 2016 from AZ but he failed to reproduce the kind of form he showed for the Dutch club.
He has managed only 31 Premier League appearances in three seasons and scored six goals in all competitions.
The Dutchman, who is on £34k-per-week, according to Spotrac.com, is surplus to requirements at the club, and Mauricio Pochettino is keen to offload him.
He enjoyed a decent 2017-18 campaign on loan at Fenerbahce, but struggled for regular opportunities last season at Spurs.
It is almost certain that he will leave the club this summer. He has no long term future under Pochettino, and should move elsewhere to seek regular opportunities.
The report claims that Anderlecht are keen to sign the 25-year-old striker.
Spurs will probably let him go if they get a decent offer for him.
Janssen could finally end his nightmare spell with Tottenham this summer should the deal materialise.