Rapidly progressive squamous lung cancer with peripheral blood eosinophilia in a 25-year-old woman: first young case report

Solid tumors combined with eosinophilia are a rare clinical presentation. To the best of our knowledge, the present report is the first to describe a case of a 25-year-old female patient diagnosed with squamous carcinoma of the lung who developed peripheral blood eosinophilia during the same period of her rapidly deteriorating condition without any obvious clinical symptoms of eosinophilia. The current case favored the diagnosis of paraneoplastic eosinophilia after excluding multiple secondary and noncancerous factors. However, the lack of bone marrow aspiration results to rule out leukemia posed a clinical diagnostic challenge. The application of glucocorticoids in combination with antineoplastic agents led to a marked decrease in peripheral blood eosinophils. The present case report emphasizes the importance of early recognition of the potential role of eosinophils in squamous lung cancer. The current report aims to provide a reference for the clinical management of similar cases.