I had symptoms of non-Hodgkin lymphoma in the spring of 2008, though I didn’t recognize them at the time. The first was a severe headache, which was initially diagnosed as a migraine. The second was a persistent dry cough, which was diagnosed as asthma.

Later, I started losing weight and sweating profusely at night. But it didn’t occur to me to mention these things to my doctors. I just thought my new diet was finally working....