Cameron, who has a history of concussions, suffered the injury in the second quarter of the Dolphins' 30-24 overtime victory over the Cleveland Browns.
Gase also said Monday that running back Arian Foster, who missed Sunday's victory with a groin injury, is unlikely to play Thursday night. Kenyan Drake started in place of Foster on Sunday, while running back Jay Ajayi scored the winning touchdown in overtime.
Gase also wouldn't commit to center Mike Pouncey making his season debut Thursday, despite the fact center Anthony Steen is likely out with a high ankle sprain. Steen has been starting for Pouncey, who has been out with a hip injury. Kraig Urbik is expected to start at center Thursday.
Cameron missed five games due to concussion issues in 2014, his last season with the Browns. He signed a two-year contract with the Dolphins in 2015 and played in all 16 games last season.
This season, he has eight catches for 60 yards and a touchdown in three games.