The 35-year-old has scored 32 goals in 75 games for the Italian outfit since joining from Bayern Munich in 2011, but his current deal expires at the end of the season.
"With how I feel at the moment, I am certain I can play one or two more years," Klose told NDR.
"However, this will be a decision that I will make year by year, month by month. Now let's see how this season goes.
"I still have a contract until next June. Then there will be the World Cup and we shall see what I will do. My decision will undoubtedly be very spontaneous."
Klose has been widely linked with a return to Germany next summer.