COMPARATIVE CYTOLOGIC FEATURES OF PANCREATIC ACINAR CELL-CARCINOMA AND ISLET-CELL TUMOR

Acinar cell carcinoma (ACC) and islet cell tumor (ICT), both rare panc reatic neoplasms, can be diagnosed accurately and rapidly with the use of imaging-guided fine-needle aspiration biopsies. The specific cytol ogic features of these tumors are described in a series of 17 patients , and histologic and immunocytochemical correlations ar-e discussed. I mportant cytologic findings in ACC are loosely cohesive clusters with cells having uniform nuclei and prominent nucleoli, cytoplasm is finel y granular and eosinophilic. Islet cell tumors show many single cells, occasional rosettes, uniform nuclei, sometimes binucleate, dense baso philic cytoplasm. Chromogranin is often positive (80%) in ICT. Trypsin and chymotrypsin were often positive (71%) in ACC. Histology was conf irmatory in all cytology cases. The recognition of cytologic features in conjunction with immunocytochemical studies can increase the diagno stic sensitivity for these neo rare tumors. (C) 1997 Wiley-Liss, Inc.