Transient elevation of squamous cell carcinoma antigen levels with influenza virus infection

We report a case of squamous cell carcinoma antigen (SCCA) elevation due to influenza B infection. A 78‐year‐old male had undergone right middle lobectomy and lymphadenectomy for lung squamous cell carcinoma two years and four months previously. His SCCA level ranged from 0.8 ng/mL to 1.9 ng/mL after the surgery. He underwent blood testing, including SCCA, as part of a regular check‐up three days after the diagnosis of the influenza B infection. His SCCA level was 17.1 ng/mL; no recurrences were found on computed tomography. One month later, his SCCA level had decreased to 1.6 ng/mL. We should keep in mind that influenza infection may cause transient elevations in SCCA levels.