A miner develops cancer of the esophagus. Ten years before, he had been exposed to radiation when he worked for a year in a mine. He had also smoked cigarettes for a number of years, but had quit five

A miner develops cancer of the esophagus. Ten years before, he had been exposed to radiation when he worked for a year in a mine. He had also smoked cigarettes for a number of years, but had quit five years ago. Which statement best describes the miner’s condition? Tests can determine whether the cancer was caused by exposure at the mine or by compounds in cigarette smoke so that a treatment can be determined. Cancer caused by exposure at the mine would have appeared while he was at the mine, so smoking is the more likely cause. The cancer is likely the result of natural exposure to radiation in the environment and not related to either the mine or smoking. It is unlikely that a specific cause can be determined, but the treatment would likely be the same in either case.