P0102 - Solid Pseudopapillary Neoplasm: Case Report of a Rare Pancreatic Tumor

Maan El Halabi, MD¹, Jamila Wynter, MD², Marcus Konner, DO¹, John D. Paulsen, MD³, David Greenwald, MD^2
1Mount Sinai St. Luke's and Mount Sinai Roosevelt, New York, NY; ²Mount Sinai Hospital, New York, NY; ³Icahn School of Medicine at Mount Sinai, New York, NY

Introduction: Solid pseudo-papillary neoplasm (SPN) is a rare low-grade malignant cystic exocrine neoplasm of the pancreas with a distinctive pathologic architecture. It is usually diagnosed incidentally, and complete resection is mainly curative with excellent long-term prognosis despite a small malignant potential.

Case Description/Methods: A 28 yo female with history of lumbar disc herniation and subsequent micro-discectomy, presented to the emergency department with a 1-day history of severe left upper quadrant abdominal pain, nausea, and vomiting. She denied any other symptom or previous trauma. On physical examination, the abdomen was soft with mild tenderness in LUQ, and no rebound or palpable mass. Lab evaluation showed a mild leukocytosis (16.5K), but otherwise liver tests and pancreatic enzymes were within normal limits.

CT scan showed an obstructing ureteral calculus and a large 7.1 cm incidental mass in the pancreatic tail with chronic splenic vein occlusion. MRCP later confirmed a 6.8 x 7.5 x 7.7 cm heterogeneous but well defined/encapsulated arising from the pancreatic tail/distal body. The lesion had heterogeneous enhancement, diffusion restriction, and areas of T1 hyperintensity.

The patient successfully underwent a laparoscopic distal pancreatectomy and splenectomy and was discharged home after 3 days. Pathology confirmed the suspected diagnosis of SPN of the pancreas with samples negative for foci of malignancy. Immuno-histochemical stains revealed tumor cells to be positive for beta-catenin, cyclin D1, CD10 and synaptophysin, while negative for chromogranin.


Discussion: SPN is considered a low-grade malignant pancreatic tumor according to the WHO Classification of Digestive System Tumors, with reported malignant transformation of around 15-16%. Despite this, SPN still has a generally excellent long-term prognosis.

SPNs have a characteristic appearance on cross-sectional imaging, appearing as a mixed solid and cystic pancreatic lesion, however cytologic analysis is usually done for confirmation of the diagnosis. The use of pre-operative biopsy or EUS-FNA has been controversial and is felt to be of limited benefit. In our patient, the post-operative cytologic diagnosis after surgery proved valuable for establishing the diagnosis with no need for pre-operative EUS-FNA.

Treatment usually is surgical resection, which is curative; appropriate clinical follow-up is warranted due to risk of local recurrence. There is no clear role for systemic chemotherapy, hormonal therapy, or radiotherapy.



Disclosures:


Maan El Halabi, MD¹, Jamila Wynter, MD², Marcus Konner, DO¹, John D. Paulsen, MD³, David Greenwald, MD². P0102 - Solid Pseudopapillary Neoplasm: Case Report of a Rare Pancreatic Tumor, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.