I wouldn’t be surprised if your husband’s current troubles are the result of the treatments, rather than a cancer recurrence. Chemo, radiation,PCI and a lobectomy in half a year is a lot to handle. This was the worst period for my wife, but eventually she got her energy back. She’s still dealing with effects 3 years out of treatment, but is very glad she was able to use all those treatments. Hey, if the docs say the tests look good, you have good reason to keep hopeful. I hope things will turn around for you two soon.