A 70-year-old woman was admitted to the Internal Medicine Division of an academic hospital because of persistent fever. She had a history of follicular lymphoma, diagnosed in 2001 and since then under remission, and of myelodisplastic syndrome. Review of systems did not reveal organ-specific complaints; moreover, chest X-rays and abdominal ultrasound did not show abnormal findings. Cultures and serology for common viruses were negative; renal function was normal. On the third hospital day, 24 h after a contrast-enhanced CT scan of thorax and abdomen (also reported as negative), the patient noticed a painful swelling in her upper neck region, worsened by swallowing.