NEW YORK - Hospital operator Tenet Healthcare Corp boosted its full-year profit forecast on Monday, citing a stronger-than-expected performance over the summer, and its shares jumped more than 10 percent.

Tenet now expects adjusted earnings before interest, taxes, depreciation and amortization of $900 million to $950 million. It previously projected $810 million to $875 million.

Our third-quarter results through August were stronger than anticipated and extended the improving trend evident in our second quarter, Chief Executive Officer Trevor Fetter said in a statement.

Dallas-based Tenet, the third-largest hospital chain behind privately held HCA Inc and Community Health Systems Inc, said hospital outpatient visits grew 3.8 percent while bad debt expense trends improved.

Tenet shares rose to $6.01 in morning trading on the New York Stock Exchange, up 10.28 percent. (Reporting by Lewis Krauskopf in New York and Susan Kelly in Chicago; Editing by John Wallace, Dave Zimmerman)