Supplementary Material for: Solid pseudopapillary neoplasm of the pancreatic head in an 18-year-old presenting with chronic intermittent abdominal pain: A case report

Background: Solid pseudopapillary neoplasm (SPN) is an uncommon pancreatic epithelial tumour of low malignant potential, seen predominantly in adolescent and young adult females. Imaging typically shows a well-circumscribed heterogeneous mass; complete resection is usually curative.
Case Presentation: An 18-year-old woman presented with ~1 year of intermittent colicky epigastric pain, vomiting, and poor oral intake, without jaundice, fever, or weight loss. Examination and routine laboratories, including liver enzymes and bilirubin, were unremarkable. Ultrasonography revealed a 4.3×4.2×6.0 cm heterogeneous lesion inferior to the pancreatic head, abutting the third part of the duodenum and contacting the superior mesenteric vein. Contrast-enhanced CT demonstrated a 4.3×5.1×4.9 cm low-attenuation, heterogeneously enhancing mass impressing the pancreatic head, compressing the third part of the duodenum, and closely related to the superior mesenteric vein; small para-aortic nodes (≤6 mm) were present. Ultrasound-guided biopsy suggested SPN. She underwent standard pancreatoduodenectomy. Gross pathology showed an encapsulated 5.5 cm tumour within the pancreatic head. Histology confirmed SPN with negative margins, no vascular or perineural invasion, and no nodal metastasis (0/1).
Case Discussion: The patient’s age, sex, and imaging features were characteristic of SPN. Head-site disease may produce duodenal compression without cholestasis. R0 resection is definitive; adverse features were absent, supporting an excellent prognosis, though structured surveillance is advisable.
Conclusion: SPN should be considered in young females with a heterogeneous pancreatic mass and non-specific upper-abdominal symptoms. Multimodal imaging, selective biopsy, and complete resection optimize outcomes.