Pancreatic Solitary Fibrous Tumor as Result of Extracranial Metastatic Disease

Case Report

Austin J Gastroenterol. 2022; 9(1): 1119.

Pancreatic Solitary Fibrous Tumor as Result of Extracranial Metastatic Disease

López-Marte P¹* and Torres-Ortíz V²

¹University of Puerto Rico-School of Medicine, Division of Gastroenterology Research, San Juan, Puerto Rico

²Ponce Health Sciences University-School of Medicine, Division of Gastroenterology, Ponce, Puerto Rico

*Corresponding author: López-Marte P, Division of Gastroenterology Research, University of Puerto Rico-School of Medicine, PB-365067, San Juan, Puerto Rico

Received: March 02, 2022; Accepted: March 22, 2022; Published: March 29, 2022

Abstract

Solitary fibrous tumors and hemangiopericytomas (SFT/HPC) are an uncommon cause of pancreatic mass, and given its rarity data is limited. In this report, we present the case of a 61-year-old Female with history of SFT/HPC brain tumor, which was evaluated with abdominal imaging after presenting with an epigastric abdominal pain. A pancreatic mass was found and after endoscopic ultrasound- fine needle aspiration biopsy, she was found with extracranial metastatic disease. Our case adds clinical awareness and knowledge to this rare entity that needs to be considered when a pancreatic mass is found.

Keywords: Solitary fibrous tumor; Hemangiopericytomas; Pancreas; Endoscopic ultrasound; Extracranial metastatic disease

Introduction

Solitary fibrous tumors and hemangiopericytomas (SFT/HPC) are rare mesenchymal neoplasms that were thought to be different identities but during recent years it was found that both share the same etiology [1-5]. This type of tumor is caused by a fusion gene between NGFI-A Binding Protein 2 gene (NAB2) and signal transducer and activator of transcription 6 gene (STAT6) fusion gene that causes expression and accumulation of STAT6 protein in the cell nuclei [2,5]. STAT6 staining of tumor cell nuclei is known to be a very reliable marker and it has been used for definitive diagnosis [6,7]. SFT/HPC’s tumors are uncommon and represent less than 1% of all central nervous system (CNS) tumors [4]. Extracranial metastatic disease is rare [8-11]. In this report we describe a case of brain SFT/HPC with metastases to pancreas diagnosed using endoscopic ultrasound guided fine needle aspiration (EUS-FNA).

Case Presentation

A 61-year-old Female with prior history of brain SFT/HPC grade 3 with recurrence presents to the clinic complaining of epigastric abdominal pain. Family medical history was non-contributory. She denied any toxic habits. Physical examination was unrevealing. On further evaluation, her laboratory work-up including cell blood count, complete metabolic panel, pancreatic enzymes and CA 19-9 level were unremarkable. She did not have any history of pancreatic disorders. Abdominal enhanced CT scan showed a large heterogeneously enhancing mass in the pancreatic body with low density areas suggestive of necrosis measuring 7.8 cm x 6.7 cm as shown in Fig.2 on coronal (a) and axial views (b). For further assessment, the patient underwent EUS- guided FNA using a 22-gauge needle. Pathology description showed a paucicellular sample with patternless pattern of cells separated by thick collagenous material (Figure 1a). Immunohistochemistry (IHC) revealed a positive result for CD34 and STAT6 (Figure 1b and 1c). These results were consistent with previous brain histological and IHC results confirming metastatic disease to pancreas. After this diagnosis, an F-18 fluorodeoxyglucose (18-FDG) PET/CT scan demonstrated an area of 7.3 x 7.0 x 7.1cm of moderately hypermetabolic mass of the body of pancreas with SUV max of 7.91. There was no evidence of other organ involvement. Since the disease was limited to the pancreas, she underwent distal pancreatectomy. The pancreas neoplasm was described as pink-tan slightly lobulated mass covered by a capsule. The margins of resection were negative for neoplasia. The patient made an uneventful recovery and currently continues with imaging and clinical surveillance.

Citation: López-Marte P and Torres-Ortíz V. Pancreatic Solitary Fibrous Tumor as Result of Extracranial Metastatic Disease. Austin J Gastroenterol. 2022; 9(1): 1119.