[StephN]

These can be very problematic.
When I was looking like NED was near when beating back my liver mets, my med onc said he wanted me to have 3 more weekly treatments of the Taxol/Navelbine/Herceptin then we would do the PET to corroberate the CT scan. By the time we did the PET there were NO hot spots and my liver was pronounced free of tumors. There were a couple of places that were then read as scars, as there had been one especially stubborn lesion on a main hepatic vein. This finally reduced to a tiny spot and has not been visible since about 3 months after that PET.

Now for my BEST "false positive" story. You may recall that I had a brain surgery in January. The brain MRI and brain PET were really bright in the old tumor bed where a large tumor had been gamma knifed a year earlier. The tumor board was really sure that the spot had all the earmarks of tumor regrowing. The tissue removed was "100% necrosis" (meaning NO tumor), to quote my brain surgeon. If the bright spot had been smaller we would have waited to check for changes in a month or two, but it was quite large and they all panicked - causing me to let them rush me into the surgery.

This disease will teach us patience, and we HER2s tend to learn that THE HARD WAY! Spots appear, we freak out, our emotions get the better of us, we can't sleep, etc. Eventually it does get easier, if, like in my case, the spots are manageable or turn out to be false positives.