Fever in patients with advanced pancreatic cancer may be caused by the tumor itself, also known as cancer fever. Patients may have fever every day, and their body temperature may rise at a fixed period of time, such as in the afternoon or morning every day. It may be caused by necrosis inside the tumor or shedding of tumor cells. In addition, patients with advanced cancer may have comorbidities, such as lung infection, and they may have fever, which is mainly caused by lung inflammation, most of which is caused by bacterial infection. It may also be caused by infection inside the abdominal cavity of the patient, such as pancreatic tumors that lead to the spread of abdominal implants and secondary abdominal infections, and the patient may also have fever and signs of peritonitis, and if necessary, abdominal CT or blood tests should be performed.