carbohydrate antigen 19 - 9 ( ca 19 - 9 ) has recently been developed of digestive tract malignancies . the ca 19 - 9 antibody has been obtained by immunizing mice with human colorectal cell line . the tumor marker ca 19 - 9 is a sensitive marker for pancreatic and hepatobiliary malignacies . the highest frequency of elevated serum ca 19 - 9 level is found in patients with pancreatic cancer . occasionally reported in other primary neoplasms , it is most often associated with the gastrointestinal tract . to the best of our knowledge , no patient with an extremely high serum ca 19 - 9 level resulting from a gastric adenocarcinoma has been reported previously . a 76-year - old man presented with right upper abdominal pain and loss of appetite . on admission , laboratory findings for white and red blood cells and platelet count were normal ; the biochemical parameters were also within normal limits . the serum level of carcinoembryonic antigen was 3.3 ng / ml ( cut - off 5.0 ng / ml ) , and the serum level of ca 19 - 9 was extremely high at 7,080 u / ml ( cut - off 37 u / ml ) . abdominal computed tomography scan showed a 5  6 cm tumor occupying the antrum and no liver metastasis . multiple biopsies showed moderately differentiated tubular adenocarcinoma of the stomach . during laparotomy , no ascites , evidence of enlargement , the tumor was removed by sharp dissection and a distal gastrectomy with d2 lymph node dissection was performed ( fig . pathological review of the resected specimen showed a poorly differentiated non - solid - type adenocarcinoma of the stomach with positive lymph node metastasis for all lymph nodes ( 21/21 lymph nodes ) ( fig . the resected specimen was evaluated as borrmann type iii , stage iiib ( pt3 , pn2 , pm0 ) . immunohistochemical study showed that ca 19 - 9-positive cells were present in the tumor ( fig . 2c , d ) . the patient was treated with 4 courses of systematic chemotherapy with cddp and ts-1 . the serum ca 19 - 9 level decreased to 4,070 ng / ml 2 months after surgery . eight months later , ascites in the abdominal cavity was observed on an abdominal computed tomography image . the serum ca 19 - 9 concentration increases to the greatest extent in patients with pancreatic cancer or cholangiocarcinoma . ca 19 - 9 resembles carcinoembryonic antigen in colorectal carcinoma and various different gastrointestinal adenocarcinomas . the expression of ca 19 - 9 has been studied in normal and malignant gastrointestinal tissues . the antigen was found by immunoperoxidase staining in 4080% of carcinomas from the gallbladder , stomach , pancreas , and colon . the association of elevated ca 19 - 9 levels with gastric carcinoma has been presented in a case report and in other studies . elevated serum levels of ca 19 - 9 have been described in 1530% of patients with gastric cancers , but these patients had multiple liver metastases . elevated ca 19 - 9 levels have been significantly correlated with lymph node metastasis , vascular invasion and liver metastasis . our patient had an exceptionally elevated ca 19 - 9 level , with a serum level over 7,000 ng / ml , and a stomach cancer without liver metastasis or peritoneal dissemination as determined by laparotomy ; at the time of death , the patient 's serum ca 19 - 9 was over 120,000 ng / ml . a high serum ca 19 - 9 level in a patient with gastric cancer is extremely rare .
carbohydrate antigen 19 - 9 ( ca 19 - 9 ) is a sensitive marker for pancreatic and hepatobiliary malignancies . 
 the highest frequency of elevated serum ca 19 - 9 levels is found among patients with pancreatic cancer . 
 ca 19 - 9 has recently been demonstrated to be a marker of digestive tract malignancies . 
 we report the case of a patient with a gastric cancer and a very high serum ca 19 - 9 level . during laparotomy 
 , a large mass was found in the antrum . 
 a distal gastrectomy with d2 dissection of the lymph nodes was performed . 
 histological examination , including immunohistochemistry , revealed an adenocarcinoma of the stomach producing ca 19 - 9 . to the best of our knowledge , 
 no patient with an extremely high serum ca 19 - 9 level resulting from a gastric adenocarcinoma has been reported previously .