Pancreatic somatostatinoma is a rare pancreatic endocrine neoplasm representing as little as 1% of pancreatic endocrine neoplasms (PENs). The histologic features of this tumor are like those of other PENs. except that it commonly forms acinar structures and often has cells with abundant, granular cytoplasm. We have recently encountered two of these neoplasms sampled by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA). We discuss the cytologic and immunohistochemical findings of these two cases and the cytologie similarities these neoplasms share with pancreatic acinar-cell carcinoma (PACC). We review the cytologic features of PEN and PACC and discuss the importance of cell block irnmunohistochemistry in the diagnosis of pancreatic neoplasia sampled by EUS-guided FNA.
- Acinar-cell carcinoma
- Endoscopic ultrasound
- Fine-needle aspiration
- Islet cell tumor
- Pancreatic endocrine neoplasm