Pancreatic Elastofibromatosis: First Case Report: 243

Introduction: Elastofibroma is a benign tumor identified by the presence of characteristic elastinophilic fibers. It was originally described as a subscapular connective tissue tumor. Over the years, it has been seen to involve other musculoskeletal sites like ischial tuberosity, greater trochanter and deltoid. It has been rarely described in GI tract (stomach and colon) as case reports but to our knowledge has never been described in pancreas. Case report: 45-year-old female with history of joint pains (HLA B27 positive, seronegative inflammatory arthritis) presented with intermittent abdominal pain of few years duration. Routine physical exam and serum chemistry were unremarkable. CT scan of abdomen revealed 1.4 by 1.4 cm hypodense lesion in the pancreatic neck, anterior to portal confluence, with no vascular involvement. Another 6 mm nodule located adjacent to it was seen, and was thought to represent a lobulation vs. a new lesion. No peri-pancreatic lymphadenopathy was seen. Subsequently, endoscopic ultrasound (EUS) was done which showed a 2.5 x 1.2 cm hypoechoic mass in the neck of pancreas (Figure 1). FNA of the pancreatic mass was non-diagnostic. Repeat EUS-FNA was reported negative for malignancy. But, since appearance of the lesion was concerning for malignancy, surgical resection was performed with central pancreatectomy. Histopathology of the resected specimen showed three well demarcated nodules of hypocellular collagen with abundant elastic fibers (highlighted by a Verhoeff's Van Gieson or VVG stain), and admixed bland spindle to stellate cells without necrosis or mitotic activity. Immunostaining of spindle cells was negative for epithelial membrane antigen (EMA), H-caldesmon, pankeratin, CD117, S100, desmin, and beta catenin nuclear stain. Hence, a diagnosis of pancreatic elastofibroma was made.Figure 1Discussion: Elastofibroma is a relatively uncommon benign tumor classically found in the musculoskeletal system. It is characterized by abnormal accumulation of elastin fibers, pathogenesis of which is unclear. Treatment is not needed unless symptomatic and surgical resection is the preferred therapeutic option. It has been rarely reported in GI tract but never in the pancreas. This case adds another entity to the differential diagnosis of pancreatic mass lesions.