2024 Volume 39 Issue 6 Pages 361-367
A 79-year-old man with fever and jaundice derived from acute cholangitis due to biliary obstruction by a pancreatic head tumor was admitted to our hospital. The patient was diagnosed with pancreatic head carcinoma and underwent pancreaticoduodenectomy after biliary drainage. Histological findings showed a solid proliferation of strongly atypical cells with conspicuous mitotic figures and pseudopapillary structures. Immunostaining showed nuclear-positive β-catenin and positive CD10, vimentin, and a high level of Ki-67 (80%); therefore, the tumor was diagnosed as a malignant solid pseudopapillary neoplasm (SPN). Multiple liver metastases occurred 2 months later, and the patient died of multiple organ failure 3 months later. SPNs are usually low-grade malignant tumors in young women; however, only a few high-grade malignant transformation SPNs have been reported. Malignant SPNs have no consistent clinical or histopathological findings. We considered the features of malignant SPN based on literature reports and the patient case.
