Softbank Hawks manager Sadaharu Oh has undergone a successful operation to remove his stomach after he was diagnosed with the early stages of stomach cancer, Keio University professor Masaki Kitajima said Tuesday.

News photoSadaharu Oh KYODO PHOTO

The surgery took place from 9:40 a.m. to 6:47 p.m. on Monday at Keio University Hospital. The surgical team found that the cancer had spread to one lymph node which they removed as well. Oh left the intensive care unit the same day and moved back to his hospital room.

Kitajima told a press conference that a patient like Oh would usually be able to leave the hospital within about 10 days, but added that his family will decide on the issue. Oh apparently said after the surgery that he is not in much pain.

"The surgery took about seven hours. He only lost about 72 cc of blood. This was good because his immune system could have weakened if we had given him a transfusion. There could be some aftereffects since he is missing the stomach, and we will explain how he should take his meals before he leaves the hospital."

Kitajima said that the cancer had not spread to any other areas.

The 66-year-old home run king announced that he would undergo surgery for a stomach tumor after a game between Softbank and the Seibu Lions at Yahoo Dome in Fukuoka on July 5.