Gastric- and intestinal-type marker expression in invasive ductal adenocarcinoma of the pancreas.
BACKGROUND
Although invasive ductal adenocarcinoma of the pancreas (PDAC) manifests as a relatively uniform histomorphological feature of the pancreatobiliary type, it may be complicated by metaplastic changes and heterogeneous gastric and intestinal elements. This study aimed to investigate the complication rate and clinicopathological significance of such heterogeneous elements.


METHODS
Fifty-nine patients who underwent resection of PDAC were examined in this study. Immunohistochemically, tumors showing high expression (>25%) of the intestinal-type (INT) marker CDX2 were classified as PDAC with INT. Those with high expression (>25%) of the gastric-type (GAS) marker MUC5AC were classified as PDAC with GAS, while those with high expression of both markers were classified as PDAC with INT/GAS. These patients were compared with those with PDAC of the negative group in which neither markers was highly expressed to examine their clinicopathological significance.


RESULTS
In the 59 patients, 31 (52.5%) showed high CDX2 or MUC5AC expression. Twenty-eight patients (47.5%) belonged to a negative group, 11 (18.6%) to a PDAC with INT group, 15 (25.4%) to a PDAC with GAS group, and 5 (8.5%) to a PDAC with INT/GAS group. No significant differences were observed for age, gender, size, localization, T classification, or prognosis among the four groups. Although the PDAC with GAS group had well differentiated types significantly more than the other groups, the rate of lymph node metastasis in this group was significantly higher (PDAC with GAS: 73%; other groups: 36%).


CONCLUSIONS
Complications with heterogeneous elements are not uncommon in PDAC, and this should be considered during the diagnosis and treatment of PDAC along with histogenesis of the disease.
First Department of Pathology, Showa University School of Medicine, Tokyo 142-8555, Japan. yuichitakano1028@yahoo.co.jp
Yuichi
Y
Takano
Nobuyuki
N
Ohike
Takuma
T
Tajiri
Kunio
K
Asonuma
Kenji
K
Harada
Hiroshi
H
Takahashi
Toshio
T
Morohoshi
D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D000071616:CDX2 Transcription Factor; D021441:Carcinoma, Pancreatic Ductal / Q000737:chemistry* / Q000401:mortality / Q000556:secondary / Q000601:surgery; D016009:Chi-Square Distribution; D005260:Female; D018398:Homeodomain Proteins / Q000032:analysis*; D006801:Humans; D007150:Immunohistochemistry; D007564:Japan; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D055271:Mucin 5AC / Q000032:analysis*; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D011379:Prognosis; D013997:Time Factors; D047368:Tumor Burden; D015854:Up-Regulation
D014408:Biomarkers, Tumor; D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; D018398:Homeodomain Proteins; C524678:MUC5AC protein, human; D055271:Mucin 5AC