Deepika Savant1, Lili Lee, Kasturi Das. 1. Department of Pathology and Laboratory Medicine, Hofstra Northwell School of Medicine, New Hyde Park, N.Y., USA.
Abstract
BACKGROUND: Intraductal tubulopapillary neoplasm of the pancreas (ITPN) is a rare tumor which was first described in 2009. We report a case with cytologic and histologic findings and discuss the pitfalls in diagnosing this entity on cytology. CASE: An 82-year-old female presented with a pancreatic body mass measuring 3.3 cm. Endoscopic ultrasound-guided fine-needle aspiration showed cells in cohesive clusters with high-grade nuclear atypia. Immunohistochemistry (IHC) showed the neoplastic cells to be positive for CK19, CD56 and chromogranin (focal). Ki-67 was high at 50-60%, and chymotrypsin was negative. On the basis of this pattern of staining, the cytologic diagnosis rendered was 'favors high-grade neuroendocrine carcinoma'. Distal pancreatic resection revealed a cystic 4-cm mass. Histologically, the tumor was seen arising from the duct with a solid growth pattern, tubule formation and papillary structures. IHC showed the tumor to be negative for chromogranin, synaptophysin, CD56, trypsin and chymotrypsin. The Ki-67 index was 70%. The final diagnosis was noninvasive ITPN. CONCLUSION: We review the literature and discuss the cytomorphologic features and IHC patterns characteristic of this new entity on cytology material in addition to the pitfalls of the cytologic diagnosis.
BACKGROUND: Intraductal tubulopapillary neoplasm of the pancreas (ITPN) is a rare tumor which was first described in 2009. We report a case with cytologic and histologic findings and discuss the pitfalls in diagnosing this entity on cytology. CASE: An 82-year-old female presented with a pancreatic body mass measuring 3.3 cm. Endoscopic ultrasound-guided fine-needle aspiration showed cells in cohesive clusters with high-grade nuclear atypia. Immunohistochemistry (IHC) showed the neoplastic cells to be positive for CK19, CD56 and chromogranin (focal). Ki-67 was high at 50-60%, and chymotrypsin was negative. On the basis of this pattern of staining, the cytologic diagnosis rendered was 'favors high-grade neuroendocrine carcinoma'. Distal pancreatic resection revealed a cystic 4-cm mass. Histologically, the tumor was seen arising from the duct with a solid growth pattern, tubule formation and papillary structures. IHC showed the tumor to be negative for chromogranin, synaptophysin, CD56, trypsin and chymotrypsin. The Ki-67 index was 70%. The final diagnosis was noninvasive ITPN. CONCLUSION: We review the literature and discuss the cytomorphologic features and IHC patterns characteristic of this new entity on cytology material in addition to the pitfalls of the cytologic diagnosis.