My aunt's blood work revealed wbc 17,400 when she was in the hospital awaiting an ellected surgery procedure. should the surgery have been cancelled?

Not necessarily: The high white count usually is due to infection and some infections require surgery, e.g., appendicitis, abscess, tissue necrosis with infection etc.

Hard to say: What was the surgery, did she have any signs or symptoms of infection? What else did her blood work show? There is too much information lacking here to make the call. We perform elective surgeries all the time with slightly elevated white counts depending on the circumstances.