The ongoing debate....was it the chicken or the egg? In my opinion, it depends what you are counting exactly...but I use my dx date to count anniversaries. My onc would count chemo (and the surgeon would count surgery!)...if I want to discuss how long I have been a survivor, I mention dx date. It was the first date I knew I had cancer and also the last known date I had cancer. But if my onc wants to measure progress for statistics or protocol, he'll measure time out from chemo tx.
Whatever it is, any anniversary is good!!
Im coming up on TEN for diagnosis, which is just mind boggling! Congrats to you too!