My dad died of non-Hodgkin's lymphoma. Not one of the hereditary ones, as far as I know. They thought, in his case, it may have been down to agricultural labor when he was younger; some of the older pesticides were heavily carcinogenic and aren't now used any more. But most cancers have multiple causes. (I work in cancer registry, and I have some awareness of how complicated this all is...the lymphomas and leukemias are especially complicated as there are so many different sub-types, all with slightly different risk factors and prognoses.)
Generally speaking, the time to be wary is if you have several close relatives on the same side of the family who all died of cancer. Particularly if it was the same one, but there are certain familial syndromes that lead to clusters of various different types. The risk is greater the younger they died, as cancers in younger people tend to be more aggressive. Also, women should look at their aunts and grandma on their father's side for breast and ovarian cancers; commonly women with clusters of these in their mother's family get checked out for the BRCA gene mutations, but you can also inherit them from your dad.
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"Grunge? Isn't that some gross shade of greenish orange?"