Pools boss Colin Cooper had been hoping to keep the 20-year-old midfielder, who has spent the last four months at Victoria Park, and was expecting to finalise an extension agreement with his parent club.
But new Middlesbrough boss Aitor Karanka wants to assess all the players in his Riverside squad and Dolan has been recalled by his parent club.
"We thought we had a deal in place but Middlesbrough have changed tack a little bit and they want their new manager to have a look at all of their players," Cooper told Pools' official website.
"It is disappointing, but we'll get on with things. We have competition for places and this gives someone else an opportunity."
The club added: "(Owners) IOR (Increased Oil Recovery) fully understand Middlesbrough's request and hope that, in the next two weeks, the position will be clarified following their assessment of Dolan."