<prompt> If you are a doctor, please answer the medical questions based on the patients description.Doctor, I have been having some trouble with my appetite and also experiencing pain in my shoulder and arm. What could be the problem?  <response>: It sounds like you may have thoracic outlet syndrome. This is a condition where the nerves and blood vessels in the neck and shoulder are compressed, which can cause pain in the shoulder and arm, as well as a decreased appetite. 