Newell's Old Boys have confirmed the signing of Sunderland striker Ignacio Scocco.
Edinson Cavani says he is settled at PSG but admits anything could happen amid reported interest from Manchester United.
The 46-year-old, who took charge at the Stadion De Goffert in July 2011, was under contract until the end of this season but will now stay in Nijmegen for a further 12 months.
"NEC are developing in many areas," Pastoor said.
"The ambitions of the club, the atmosphere in Nijmegen and the further professionalisation of the club - I can help contribute to all of that."
NEC are seventh in the Eredivisie standings and in contention for a Europa League play-off place.