Hi Koala, is this the 'forgotten cancers' study? My husband and I both participated (my husband has no family in Aus, so I did the study as someone who has had a similar lifestyle to him). It will not immediately benefit anyone, but will provide more information about people who developed the less well known cancers, and so may lead to some useful conclusions in the future. It's completely voluntary, so fee free to do whatever you like.
Emily