A joint statement issued by the Vatican and the Gemelli hospital in Rome said that the tumour was removed from the Pope's colon during an operation yesterday morning lasting nearly four hours.
Corrado Manni, the anaesthetist, said that the Pope's body responded to the operation 'not like a 72-year-old but like a 20-year-old'.
According to Dr Manni, a piece of intestine between six and eight inches long had to be cut in the sigmoid tract of the large intestine, the area where the colon bends before the intestine ends in the rectum.
The statement said the Pope's gall bladder was removed after doctors found stones in it. Removal of the gall bladder is one of the most common major operations. People can live fairly normal lives without a gall bladder, which stores bile which aids in the digestion of fats. The Vatican spokesman, Joaquin Navarro, said a biopsy performed before the operation and another during surgery showed that the tumour was benign.
The statement said further tests on the tumour would be carried out as is customary. Examination of intestinal tissue removed for further diagnostic tests would take three days.
The cardiologist, Attilio Maseri, said after the operation that the tumour appeared to be about '99 per cent benign', apparently leaving open the possibility that there may have been the beginnings of malignant cell growth.
But Mr Navarro, asked at a news conference if he could confirm that no malignancy was found, said: 'Yes, it is confirmed 100 per cent.'
Dr Francesco Crucitti, who headed the surgical team, also said the tumour was 'absolutely benign'. He said that the Pope should be able to recover fully and not have to cut back on his gruelling schedule.
The hospital had the air of being under siege yesterday, with rows of praying nuns in the courtyard, crowds of journalists in the hall and lines of ambassadors' limousines outside.
But corridors were kept clear and the running of the clinic, part of the Roman Catholic Sacred Heart university, was not disturbed, a spokesman said. The 1,706-bed clinic is one of Rome's largest and most modern hospitals.
The Pope is expected to make his next international trip in October, when he is due to visit the Dominican Republic and other countries to commemorate the 500th anniversary of Columbus's discovery of America.
Whirlwind of change, page 13