This is a drug study. One where the OP was aware of a small risk of a certain type of cancer. Not that the drug causes that cancer, but that there seems a non-random correlation between those who take the drug and those who get the cancer. OP was warned of this and all other side effects found in the first phases of the study and still chose to participate.
Where do you think the risk statistics come from?
While there are some evil drug companies who violate ethical protocols of drug testing for profit, that does not seem what has happened here. (Absent anything more.) There is no negligence as far as we can tell, we're just thinking of a strict liability under product liability. But, like a knife, some things can't be made safely. I'm thinking experimental drugs would fall under that as well as the warning of known risks. C'mon. If adverse results cause huge liability, we might as well forget about any new drugs ever coming on line.