S3253 Incidental Finding of Solid Pseudopapillary Neoplasm (SPN) Following a Motor Vehicle Accident: A Case Study

Introduction: Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare, low-grade malignant tumor predominantly affecting non-White women in their 30s–40s. It features pseudopapillary structures and is often found incidentally. While generally indolent with excellent prognosis after resection, SPN can show local invasion or metastasis. We report an 18-year-old African American woman diagnosed with SPN after a motor vehicle accident, highlighting its underreported incidence in the United States and importance in differential diagnoses. Case Description/Methods: An 18-year-old African American woman with no significant medical history presented after a high-speed motor vehicle accident, reporting cervical tenderness. Initial trauma evaluation and FAST ultrasound were unremarkable. However, a pan-scan, including contrast-enhanced abdominal computed tomography revealed a 1.4 cm low-attenuating mass in the pancreatic head. Eight months later, esophagogastroduodenoscopy with endoscopic ultrasound (EUS) identified a 2.0 × 2.9 cm oval mass in the uncinate process without local invasion. Fine-needle aspiration confirmed a low-grade neoplasm consistent with SPN. Immunohistochemistry was positive for β-catenin. The patient is currently awaiting surgical consultation. Discussion: SPN is classified by the World Health Organization as a low-grade malignant pancreatic tumor primarily affecting young non-White women. It accounts for 0.2%–2.7% of all pancreatic neoplasms. Though 5 times more common in women, SPN may follow a more aggressive course in men. Most SPNs are discovered incidentally—such as during trauma work-ups. Symptoms may include abdominal pain, nausea, palpable mass, or jaundice. Diagnosis often involves endoscopic ultrasound-guided fine needle aspiration. Histologic features include pseudopapillary structures with fibrovascular cores, nuclear grooves, and eosinophilic cytoplasmic globules. A key molecular feature is mutation of the CTNNB1 gene, causing nuclear β-catenin accumulation—confirmable by immunohistochemistry and essential for distinguishing SPN from other pancreatic tumors. Surgical resection is the preferred treatment, achieving 5-year survival rates above 90%. Around 15% of cases may exhibit high-grade features, including vascular invasion or liver metastases. In such cases, targeted therapies show promise, though more research is needed. As imaging becomes more prevalent, SPN incidence may rise. This case highlights the need for awareness, particularly among underrepresented groups such as African American women in the United States.