The significance of CD44 expression in gastrointestinal neuroendocrine tumors.
OBJECTIVE
Expression of CD44 and its isoforms has been demonstrated to be a prognostic marker in many neoplasms. Gastrointestinal neuroendocrine tumor is a slow-growing neoplasm, whose behavior is determined by site of occurrence, size or specific histologic growth pattern. In this study, the feasibility of using CD44 as a prognostic marker in gastrointestinal neuroendocrine tumor is evaluated.


METHODS
Representative paraffin-embedded sections of gastrointestinal neuroendocrine tumor from 22 patients were studied by immunohistochemical staining using monoclonal antibodies against CD44, Ki-67, and p53 retrospectively. The correlation between these markers and clinical behavior of the tumors was analyzed.


RESULTS
Positive expression of CD44 was observed in 15 cases (68%) of gastrointestinal neuroendocrine tumor. Expression of CD44 showed significant inverse correlation with lymph node status (P=0.049), distant metastasis (p<0.001) and mortality (p=0.002). Neither p53 nor Ki-67 correlated with lymph node status, distant metastasis and overall survival. Both lymph node status and distant metastasis showed strong correlation to survival after multivariate analysis. Patients with the tumor growing from the hindgut had better survival (p=0.024). The patients with stronger CD44 immunoreactivity (> or = 2+) tumors had significantly favorable survival (p=0.004) compared with those with weaker immunoreactivity (< or = 1+) tumors.


CONCLUSIONS
Expression of CD44 in gastrointestinal neuroendocrine tumor inversely correlates with tumor metastasis, associates with a favorable outcome and may serve as one of the prognostic indicators.
Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Chao-Han
CH
Lai
Yan-Shen
YS
Shan
Edgar D
ED
Sy
Yu-Hsiang
YH
Hsieh
Hung-Wen
HW
Tsai
Jenq-Chang
JC
Lee
Pin-Wen
PW
Lin
D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D005770:Gastrointestinal Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D006801:Humans; D018960:Hyaluronan Receptors / Q000378:metabolism*; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D018358:Neuroendocrine Tumors / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
D018960:Hyaluronan Receptors; D019394:Ki-67 Antigen; D016159:Tumor Suppressor Protein p53