Prognostic significance of the labeling of Adnab-9 in pancreatic intraductal papillary mucinous neoplasms.
BACKGROUND
Pancreatic intraductal papillary mucinous neoplasms (IPMN), morphologically resembling colonic adenomas, often have an indefinable malignant potential. We used a monoclonal antibody (MAb) raised against colonic adenomas, Adnab-9, to identify patients with a better prognosis.


METHODS
We assessed Adnab-9-labeled sections of these neoplasms from 50 patients, 13 pancreatic adenocarcinomas, and 32 colonic adenomas using standard immunohistochemical techniques.


RESULTS
26% of the IPMNs labeled with Adnab-9 as compared to 0% of pancreatic ductal cancers or surrounding benign tissues, (p < 0.001) and 53% of adenomas (p < 0.025). Labeling in IPMNs was usually seen in the noninvasive epithelium suggesting that Adnab-9 is a premalignant marker in these lesions. Labeling of invasive IPMN's identified a group of patients with a superior overall survival (p = 0.027).


CONCLUSIONS
Adnab-9 labeling-characteristics appear similar for both IPMNs and adenomatous polyps, suggesting that they are analogous lesions. Adnab-9 labeling may also be a useful prognostic marker for invasive intraductal papillary mucinous neoplasms.
Tobi
M
M
Department of Medicine and Pathology, John D. Dingell Veterans Affairs Medical Center, Detroit, Michigan 48201, USA. martin.tobi@med.va.gov
Hatfield
J
J
Adsay
V
V
Galagan
K
K
Kozarek
R
R
Inagaki
M
M
Kasai
S
S
Tokusashi
Y
Y
Obara
T
T
Hruban
R H
RH
Lough
J
J
Barkun
A N
AN
Jabbari
M
M
Sheikh
R
R
Ruebner
B
B
Lawson
M J
MJ
Ben-Josef
E
E
Fligiel
S
S
D002288:Adenocarcinoma, Mucinous / Q000378:metabolism* / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal; D023082:Defensins / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000378:metabolism* / Q000473:pathology*; D011379:Prognosis
D000911:Antibodies, Monoclonal; D023082:Defensins