[sexobon]

You raised a red flag:

"Unexplained weight loss is cancer unless proven not," she says. It could, of course, turn out to be another condition, such as an overactive thyroid.

Expect your doctor to run tests to check the thyroid and perhaps order a CT scan of different organs. The doctor needs to "rule out the possibilities, one by one," Mishori says.

Search parameter "unexplained weight loss and cancer" for related info.