Abstract Neoplastic fever (NF) is a paraneoplastic syndrome that is encountered in a significant proportion of patients with cancer. We present the case of a 37 year old female with matastatic renal transitional cell carcinoma. She was hospitalized with fever, constitutional symptoms, and worsening performance status. There was no identifiable infection source. In the third week of hospitalization, she was started on naproxen, resulting in complete lysis of fever, control of constitutional symptoms and improvement in performance status. She was discharged the next day and died of advanced disease within two months. Workup of NF can lead to unnecessary and prolonged hospitalization in patients near the end of their life, resulting in significant suffering. While it is important to rule out infection, an early trial of naproxen is inexpensive and, in patients who can tolerate NSAIDs, may provide good control for NF.