[Malignant solid tumor associated with hypereosinophilic syndrome].

Hypereosinophilic syndrome is characterized by chronic eosinophil overproduction, resulting in multiple organ damages due to eosinophil infiltration and mediator release. According to the etiology, we distinguish between myeloproliferative disorders, parasitic infections, solid tumors, T-cell lymphomas and idiopathic forms. In our case report, the 49-year-old man was hospitalized with weight loss, leg edema and tachycardia. In his laboratory tests increased biliary obstructive parameters as well as extreme leukocytosis and eosinophilia had been highlighted. We started our evaluation with a strong suspicion of hematologic malignancy. The CT scan of the thorax, abdomen and pelvis described hepatosplenomegaly, multiple intrahepatic lesions and an uncertain solitary cystic lesion in the tail of the pancreas with abnormal lymph nodes and pleural fluid. The described CT image and the other clinical parameters were primarily consistent with the manifestation of chronic myeloid leukemia. However, the diagnosis was not confirmed by peripheral blood smear, flow cytometry, bone marrow biopsy or genetic tests. After these results, we continued the assessment towards solid tumor associated leukemoid reaction, core biopsy was performed to verify the liver lesions. The biopsy confirmed the infiltration of a poorly differentiated epithelial tumor as a metastasis of pancreatobiliary carcinoma. To the best of our knowledge, this is the first case report on hypereosinophilic syndrome associated with gastrointestinal solid tumors in the Hungarian medical literature. It draws attention to the differential diagnosis of extreme leukocytosis and eosinophil ratios and by the absence of confirmed hematological disease the importance of early biopsy sampling of solid lesions.