But in 2022, Alberto became unwell and tests showed he had a rare cancerous tumour growing on his duodenum, which is at the top of the small intestine.

In 1994 he performed the world’s first six-organ transplant, replacing a patient’s stomach, small intestine, duodenum, pancreas, liver and kidney in a single operation.

The other substance, called intrinsic factor, mixes with the stomach's contents and travels with them into the first part of the small intestine — the duodenum.

In 1996, he received a five-organ transplant at the University of Pittsburgh that replaced his stomach, duodenum, pancreas, intestine and liver after suffering intestinal failure due to a hereditary defect.

The tube is inserted through the patient’s mouth and stomach, then into the first part of the small intestine, called the duodenum.