Introduction:
Solid pseudopapillary neoplasm (SPN) of the pancreas is an exceedingly rare tumor, accounting for 0.2% to 2.7% of all pancreatic neoplasms, predominantly affecting young females.

Aim:
The aim of this study is to highlight a rare presentation of SPN as persistent fever of unknown origin (FUO) without other significant symptoms, emphasizing the need to include pancreatic neoplasms in FUO differential diagnosis.

Case Study:
An 18-year-old female presented with persistent FUO without other significant symptoms. Initial laboratory tests were largely unremarkable except for mild anemia. Imaging studies revealed a well-defined mass in the tail of the pancreas measuring 5 × 5 × 6 cm. An ultrasound-guided core needle biopsy suggested SPN, characterized by monomorphic cells with minimal atypia and a specific immunophenotype. The patient underwent a distal pancreatectomy with splenectomy. Histopathological examination confirmed the diagnosis of SPN (pT3 pN0 LVI− PNI+), with clear surgical margins and no lymph node involvement. The postoperative course was uneventful, and follow-up examinations showed no signs of recurrence.

Results and Discussion:
This case underscores the importance of considering pancreatic neoplasms in the differential diagnosis of FUO, even in young patients. Early detection and surgical intervention are crucial for favorable outcomes.

Conclusions:
SPN is a rare low-grade malignant tumor with good prognosis following surgical resection. Increased clinical awareness of its atypical presentations is essential for timely diagnosis and treatment.