title: High expression of tumor-associated antigen RCAS1 in pancreatic ductal adenocarcinoma is an unfavorable prognostic marker.
abstract: RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is a recently identified human tumor-associated antigen expressed on various cancer cells. It is thought that tumor cells evade immune surveillance by expression of RCAS1, which induces apoptotic cell death in receptor-positive immune cells. The purpose of our study was to investigate the relation between RCAS1 expression and the clinicopathological variables and clinical outcome in patients with pancreatic adenocarcinoma. Immunohistochemical analysis for RCAS1 was performed on paraffin-embedded specimens of 80 patients (mean age, 62 years) who underwent surgical resection for pancreatic adenocarcinoma. Of the 80 specimens, 77 (96%) were positive for RCAS1. No significant correlation was found between RCAS1 expression and age, gender, depth of invasion, tumor diameter, surgical margin, lymphatic invasion, venous invasion or histopathological grading. Borderline correlations between RCAS1 expression were noted for lymph node metastasis and stage (p = 0.0608 and 0.0934, respectively). RCAS1 expression was very frequently observed and the survival of patients with high RCAS1 expression was significantly shorter than that of those with low expression (p = 0.0012). Multivariate analysis using the Cox regression model indicated that high RCAS1 expression was an independent prognostic factor (risk ratio, 3.090; p = 0.0090). These results suggested that RCAS1 might be a significant tumor marker for pancreatic adenocarcinoma and an unfavorable predictor for prognosis of patients who have undergone surgical resection.
authors: Surgical Oncology, Cancer Medicine, Division of Cancer Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan. hiraoka@med.hokudai.ac.jp
authors: Kei
authors: K
authors: Hiraoka
authors: Yasuhiro
authors: Y
authors: Hida
authors: Masaki
authors: M
authors: Miyamoto
authors: Taro
authors: T
authors: Oshikiri
authors: Masato
authors: M
authors: Suzuoki
authors: Yoshihiro
authors: Y
authors: Nakakubo
authors: Toshiya
authors: T
authors: Shinohara
authors: Tomoo
authors: T
authors: Itoh
authors: Toshiaki
authors: T
authors: Shichinohe
authors: Satoshi
authors: S
authors: Kondo
authors: Noriyuki
authors: N
authors: Kasahara
authors: Hiroyuki
authors: H
authors: Katoh
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000378:metabolism*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000951:Antigens, Neoplasm; D000954:Antigens, Surface / Q000096:biosynthesis*; D021441:Carcinoma, Pancreatic Ductal / Q000175:diagnosis / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000378:metabolism*; D011379:Prognosis; D016016:Proportional Hazards Models; D013997:Time Factors
chemical_list: D000951:Antigens, Neoplasm; D000954:Antigens, Surface; C120762:EBAG9 protein, human