Computed tomography features of acinar cell carcinoma of the pancreas

Abstract

It was with great interest reading Raman et al.’s article [1] on depicting computed tomography (CT) findings of pancreatic acinar cell carcinoma (ACC). The article significantly expands our current knowledge on the CT imaging characteristics of this very rare pancreatic malignancy. The diagnosis of ACC is typically difficult and is usually suspected based on the CT imaging characteristics of the lesion. Therefore, we wanted to discuss a patient with ACC using CT and endoscopic ultrasound (EUS) findings that expand on the data presented by Raman et al. Our patient is a 58-year-old man who developed bleeding from isolated gastric varices. The bleeding was spontaneously resolved. CT of the abdomen showed large (9 cm) hypodense pancreatic mass, which occupied most of the body and tail of the pancreas. There was splenic and portal vein involvement and extensive collateral circulation (Fig. 1). CA 19-9 level was normal. EUS showed hypoechoic, heterogeneous pancreatic mass, and portal vein thrombosis (Fig. 2). EUS-guided fine needle aspiration (FNA) revealed acinar-like cells consistent with ACC. The patient underwent subtotal distal pancreatectomy with splenectomy and en-bloc resection of a portion of the portal vein, portal vein thrombectomy, and veno-venous bypass. All removed lymph nodes were negative for malignancy. The patient has been doing well with no evidence of recurrence over a follow-up period of 7 months. In our case, none of CT imaging characteristics suggesting ACC reported by Raman et al. [1] were present except for the large size of the mass. Specifically, there was no evidence of exophytic, cystic or necrotic component or enhancing tumor capsule. Indeed, these findings are not universally present in all cases (73 % exophytic lesion, 53 % cystic or necrotic component, and 53 % enhancing capsule) [1]. Therefore, based on CT imaging characteristics alone it might be impossible to distinguish ACC from the much more common pancreatic ductal adenocarcinoma. Our case concurs with the conclusion Correspondence to: Disaya Chavalitdhamrong; email: disaya@gicapsule. com Fig. 1. Computed tomography of the abdomen shows large hypodense pancreatic mass.