Hypereosinophilia‐related liver pseudotumor with elevated interleukin‐5 levels preceding T‐cell lymphoma

A 61‐year‐old woman with hypereosinophilia and elevated interleukin (IL)‐5 level was admitted to our hospital after detection of multiple liver tumors. Liver biopsy demonstrated that the tumor consisted of scar tissue with remnants of eosinophilic infiltration, suggesting that it had formed by massive eosinophilic infiltration. The hypereosinophilia was treated mainly by prednisolone, and thereafter, the liver tumors disappeared. However, 10 months postadmission, CD4+ T‐cell lymphoma, which can produce IL‐5, was detected in the nasopharynx and oropharynx. Therefore, we believe that this is a rare case of hypereosinophilia‐related liver pseudotumor induced by presumed by IL‐5 elevation.