99.9% sure from Pet Scan

My father went into the hospital Christmas Eve for A-Fib,  He was admitted.  The doctors did a cat-scan and found the mass in his left lung.  On Monday they did a pet scan and on Tuesday and Wednesday they tried to do a biopsie but was unsuccessful.  The results from the pet scan came back on New Year's Eve,  they said they were 99.9% sure he had cancer.  The limp-nods along his esphogas was possibly stage 4.  Today my dad had surgery.  They went in took some limp-nods and then opened his left side and remove the part of the lung with the mass.  The doctor said he doesn't have cancer and not sure why the pet scan showed what it did.  I'm so confused.  How does that happen?  Not saying I'm not happy but is this the calm before the storm???

[juliabaroff]

iam sure youve already figured it out by know but a biopsy is the only way to know 100% if its cancer or not.