TY - JOUR
T1 - Intraductal tubulopapillary neoplasms of the pancreas distinct from pancreatic intraepithelial neoplasia and intraductal papillary mucinous neoplasms
AU - Yamaguchi, Hiroshi
AU - Shimizu, Michio
AU - Ban, Shinichi
AU - Koyama, Isamu
AU - Hatori, Takashi
AU - Fujita, Izumi
AU - Yamamoto, Masakazu
AU - Kawamura, Shunji
AU - Kobayashi, Makio
AU - Ishida, Kazuyuki
AU - Morikawa, Takanori
AU - Motoi, Fuyuhiko
AU - Unno, Michiaki
AU - Kanno, Atsushi
AU - Satoh, Kennichi
AU - Shimosegawa, Tooru
AU - Orikasa, Hideki
AU - Watanabe, Tomoo
AU - Nishimura, Kazuhiko
AU - Ebihara, Yoshiro
AU - Koike, Naoto
AU - Furukawa, Toru
PY - 2009/8
Y1 - 2009/8
N2 - We have encountered cases of unusual intraductal pancreatic neoplasms with predominant tubulopapillary growth. We collected data on 10 similar cases of "intraductal tubulopapillary neoplasms (ITPNs)" and analyzed their clinicopathologic and molecular features. Tumor specimens were obtained from 5 men and 5 women with a mean age of 58 years. ITPNs were solid and nodular tumors obstructing dilated pancreatic ducts and did not contain any visible mucin. The tumor cells formed tubulopapillae and contained little cytoplasmic mucin. The tumors exhibited uniform high-grade atypia. Necrotic foci were frequently observed, and invasion was observed in some cases. The ITPNs were immunohistochemically positive for cytokeratin 7 and/or cytokeratin 19 and negative for trypsin, MUC2, MUC5AC, and fascin. Molecular studies revealed abnormal expressions of TP53 and SMAD4 in 1 case, but aberrant expression of β-catenin was not observed. No mutations in KRAS and BRAF were observed in the 8 cases that were examined. Eight patients are alive without recurrence, 1 patient died of liver metastases, and 1 patient is alive but had a recurrence and underwent additional pancreatectomy. The mitotic count and Ki-67 labeling index were significantly associated with invasion. All the features of ITPN were distinct from those of other known intraductal pancreatic neoplasms, including pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasm, and the intraductal variant of acinar cell carcinoma. Intraductal tubular carcinomas showed several features that were similar to those of ITPN, except for the tubulopapillary growth pattern. In conclusion, ITPNs can be considered to represent a new disease entity encompassing intraductal tubular carcinoma as a morphologic variant.
AB - We have encountered cases of unusual intraductal pancreatic neoplasms with predominant tubulopapillary growth. We collected data on 10 similar cases of "intraductal tubulopapillary neoplasms (ITPNs)" and analyzed their clinicopathologic and molecular features. Tumor specimens were obtained from 5 men and 5 women with a mean age of 58 years. ITPNs were solid and nodular tumors obstructing dilated pancreatic ducts and did not contain any visible mucin. The tumor cells formed tubulopapillae and contained little cytoplasmic mucin. The tumors exhibited uniform high-grade atypia. Necrotic foci were frequently observed, and invasion was observed in some cases. The ITPNs were immunohistochemically positive for cytokeratin 7 and/or cytokeratin 19 and negative for trypsin, MUC2, MUC5AC, and fascin. Molecular studies revealed abnormal expressions of TP53 and SMAD4 in 1 case, but aberrant expression of β-catenin was not observed. No mutations in KRAS and BRAF were observed in the 8 cases that were examined. Eight patients are alive without recurrence, 1 patient died of liver metastases, and 1 patient is alive but had a recurrence and underwent additional pancreatectomy. The mitotic count and Ki-67 labeling index were significantly associated with invasion. All the features of ITPN were distinct from those of other known intraductal pancreatic neoplasms, including pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasm, and the intraductal variant of acinar cell carcinoma. Intraductal tubular carcinomas showed several features that were similar to those of ITPN, except for the tubulopapillary growth pattern. In conclusion, ITPNs can be considered to represent a new disease entity encompassing intraductal tubular carcinoma as a morphologic variant.
KW - IPMN
KW - Intraductal tubular neoplasm
KW - Intraductal tubulopapillary neoplasm
KW - PanIN
KW - Pancreatic cancer
UR - http://www.scopus.com/inward/record.url?scp=68249090042&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=68249090042&partnerID=8YFLogxK
U2 - 10.1097/PAS.0b013e3181a162e5
DO - 10.1097/PAS.0b013e3181a162e5
M3 - Article
C2 - 19440145
AN - SCOPUS:68249090042
SN - 0147-5185
VL - 33
SP - 1164
EP - 1172
JO - American Journal of Surgical Pathology
JF - American Journal of Surgical Pathology
IS - 8
ER -