title: Loss of PTEN expression in neuroendocrine pancreatic tumors.
abstract: PTEN (phosphatase and tensin homologue deleted from chromosome 10) is a well established tumor suppressor gene, which was cloned to chromosome 10q23. PTEN plays an important role in controlling cell growth, apoptosis, cell adhesion, and cell migration. In various studies, a genetic change as well as loss of PTEN expression by different carcinomas has been described. To date, the role of PTEN as a differentiation marker for neuroendocrine tumors (NET) and for the loss of PTEN expression is still unknown. It is assumed that loss of PTEN expression is important for tumor progression of NETs. We hypothesize that PTEN might be used as a new prognostic marker. We report 38 patients with a NET of the pancreas. Tumor tissues were surgically resected, fixed in formalin, and embedded in paraffin. PTEN expression was evaluated by immunohistochemistry and was correlated with several clinical and pathological parameters of each individual tumor. After evaluation of our immunohistochemistry data using a modified Remmele Score, a widely accepted method for categorizing staining results for reports and statistical evaluation, staining results of PTEN expression were correlated with the clinical and pathological parameters of each individual tumor. Our data demonstrates a significant difference in survival with existence of lymph node or distant metastases. Negative patients show a significant better survival compared with positive patients. Furthermore, we show a significant difference between PTEN expression and WHO or TNM classification. Taken together, our data shows a positive correlation between WHO classification and the new TNM classification of NETs, and loss of PTEN expression as well as survival. These results strongly implicate that PTEN might be helpful as a new prognostic factor.
authors: Department of General, Visceral and Pediatric Surgery, Heinrich-Heine University of Düsseldorf, Germany. krausch@med.uni-duesseldorf.de
authors: M
authors: M
authors: Krausch
authors: A
authors: A
authors: Raffel
authors: M
authors: M
authors: Anlauf
authors: M
authors: M
authors: Schott
authors: H
authors: H
authors: Willenberg
authors: N
authors: N
authors: Lehwald
authors: D
authors: D
authors: Hafner
authors: K
authors: K
authors: Cupisti
authors: C F
authors: CF
authors: Eisenberger
authors: W T
authors: WT
authors: Knoefel
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018358:Neuroendocrine Tumors / Q000145:classification / Q000201:enzymology* / Q000473:pathology; D051059:PTEN Phosphohydrolase / Q000172:deficiency* / Q000378:metabolism; D010190:Pancreatic Neoplasms / Q000145:classification / Q000201:enzymology* / Q000473:pathology; D016019:Survival Analysis; D014944:World Health Organization; D055815:Young Adult
chemical_list: D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human