They have called numerous times. I answered today and a female voice said hello after I did and waited for me to say something else. Since she called me I didn't say anything and hung up. This is obviously a scam of some form.
Caller ID says "Cancer Research" and they hang up when answer machine starts. Calls are from early morning until about 9:00 at night, usually 2-3 times per day. After some internet searching I found it was actually from "The American Institute for Cancer Research." Unless they have changed since a previous in-depth look they do a lot of direct mail soliciting and insert a bit of educational material with the pitch, allowing them to claim a large part of the soliciting expense as "cancer education." That greatly increases the portion of their income that can be claimed as going to "programs" rather than fund-raising expense but it's deceptive. I went to www.aicr.org and sent an e-mail asking to be taken off off their call list immediately. You can also try the telephone menu tip mentioned in a recent post. Good luck!