James Potten, 37, got a grisly shock when he received a FedEx package emblazoned "patient tumor - specimen enclosed" when he was expecting the Amazon ebook reader.
The parcel he received was supposed to go to the Royal Free Hospital in London but ended up on his doorstep instead after a delivery mix-up.
Mr Potten, of Clifton, Bristol, said he had received a parcel from an address in California.
"When I opened it I had quite a shock," he told the BBC.He said FedEx had contacted him on Thursday, January 7 to inform him they had attempted to deliver a parcel but were unable as he wasn't home. The driver then returned to his house later on that day.
Mr Potten, an environmental consultant, said:
"My name was on the outside, but the contents weren't what I expected. "I haven't opened the sealed box, which says exempt patient tissue, as it doesn't belong to me. “I don't know where my Kindle is, but if it is at the Royal Free I'd be happy to do an exchange."