<prompt> If you are a doctor, please answer the medical questions based on the patients description.i am a pancreatic cancer patient. earlier this week i had a high fever, vomitting, chills, and sweats. now 3 days later i still have no energy and am very weak. i get a little lightheaded when i try to get up. i had bllod and urine work done while in the ER, but it showed nothing...i also have a little back pain  <response>: Hi.any type of cancer could produce those systemic symptomatologic that you enumerated especially if the lab worksancillary studies done are all normal. It is your body reacting to the changes in your body brought about by the cancer itself. I advise you to have a close follow-up with your doctor. Treatment for this constitutional symptoms secondary to malignancy are usually symptomatic. Hope this helps. Good day!! Chat Doctor. 