Krispy Kreme Doughnuts Inc. cut its adjusted earnings forecast for the full year as it expects a rise in costs related to technology upgrades and management changes, sending its shares down sharply in extended trading Monday.

The company cut its fiscal 2015 adjusted earnings forecast to 69-74 cents per share from 73-79 cents.

Analysts on average were expecting earning of 78 cents per share, according to Thomson Reuters I/B/E/S.

Krispy Kreme, best known for its glazed doughnuts, said revenue for the first quarter ended May 4 rose 0.79 percent to $121.58 million.

At about 5:30 p.m. in New York, Krispy Kreme's shares were down 10 percent at $17.09, after gaining less than 1 percent during the regular New York Stock Exchange session to close at $19.