Causes of throat cancer can be unclear, a health professional has suggested.
Martin Ledwick, head cancer information nurse at Cancer Research UK, said that there doesn't always seem to be an "obvious cause" as to why a person develops the disease.
The comment comes as Oscar-winning actor Michael Douglas has been diagnosed with throat cancer.
Douglas' spokesperson told People magazine that the 65-year-old star is to undergo eight weeks of radiation and chemotherapy.
However, his doctors are expecting him to make a full recovery, the representative added, noting that the actor himself is "very optimistic" about the situation.
Mr Ledwick added: "There are a number of different types of cancer that can affect the throat. Smoking increases the risk of developing most of them, but there could also be other causes depending on the exact type of throat cancer."
Cancer Research UK noted that throat cancer can refer to a number of different areas and as such it is not a precise medical term.