It was only the second time PSV had conceded six goals at home in the Eredivisie and there was little warning of events to come at half-time with the score at 1-1, Vitesse having taken the lead through Lucas Piazon before the hosts equalised through Memphis Depay.
Mike Havenaar and Kelvin Leerdam gave the visitors a 3-1 lead with 15 minutes remaining before Karim Rekik pulled one back with six minutes to go.
Two goals from Davy Propper sandwiched Patrick van Aanholt's strike as Vitesse sealed their fifth successive win in style.
Two points behind Peter Bosz's side in second are Ajax, who kept a sixth clean sheet in their past nine Eredivisie home games. Davy Klaassen was the hero for the hosts against NAC Breda with two first-half goals before completing his hat-trick in the 64th minute.
Bojan Krkic came off the bench to add the fourth just four minutes later and Breda saw Joey Suk dismissed two minutes from the end as Ajax sealed their fourth consecutive league victory to stay in touch with the leaders.
Twente are a point further back in third after coming from behind to win 2-1 win at AZ.
Roy Beerens gave the hosts the perfect start in the third minute, but Youness Mokhtar levelled the scores in the 39th minute before stealing all three points with a last minute winner.
Elsewhere, RKC Waalwijk drew 2-2 at home with Cambuur.
Robert Braber gave RKC the lead after 16 minutes before two goals in four minutes from Michiel Hemmen turned the match around.
The hosts equalised nine minutes into the second half through Sander Duits' penalty before they saw Damiano Schet sent off for a second bookable offence with seven minutes to go.
