Clinical Pathological Features And Prognosis Of Patients With Serum AFP Positive Gastric Cancer

BackgroundAlpha-fetoprotein(AFP)is mainly produced by yolk sac epithelium and embryonic liver,which belongs to embryonic serum protein.And it is a specific tumor marker for diagnosing hepatocellular carcinoma and reproductive system malignancy.In addition,elevated serum AFP is also found in other malignant tumors of endoderm origin,including gastric cancer.In particular,Boureill et al.first reported in 1970 that serum AFP was elevated in a patient with gastric cancer accompanied with liver metastases,and the concept of alpha-fetoprotein-producing gastric cancer(AFPGC)emerged.With case reports and further studies on AFP-positive gastric cancer,AFPGC patients have the poor characteristics such as high rate of liver metastases,high incidence of lymphatic infiltration,higher clinical staging,worse prognosis and so on.At present,studies on this kind of gastric cancer are mainly based on case reports.And clinical pathological features and prognostic factors of AFPGC have been few studied.Meanwhile,the specific pathway for AFPGC liver metastasis and the reasons for its low survival rate have not been fully clarified.ObjectiveClinically,AFPGC is a rare subtype of gastric cancer.The clinicopathological features of 16 patients with serum AFP-positive gastric cancer from January 2013 to March 2016 in the Jinan Central Hospital Affiliated to Shandong University were retrospectively analyzed.To explore the clinicopathological features and prognostic features,and to analyze the specific pathways of liver metastasis of gastric cancer and the role of AFP in predicting the location of gastric cancer.Methods251 patients with gastric cancer admitted to the Department of Gastroenterology,Gastrointestinal Surgery and Oncology Department,Jinan Central Hospital Affiliated to Shandong University,were respectively collected from January 2013 to March 2016.1n accordance with inclusion and exclusion criteria,preoperative serum levels and excluding AFP-increased diseases such as primary liver cancer,embryonal tumor,and active hepatitis,there are a total of 139 remaining cases.In accordance with whether the AFP level was normal or not,they were divided into AFP positive group(ie,AFPGC group)and AFP negative group(ie,non-AFPGC group).Pretreatment variables were analyzed,including age,sex,tumor site,tumor size,peripheral lymph node metastasis,depth of invasion,clinical stage,surgical methods,Helicobacter pylori(Hp)infection,and follow-up of patients in both groups.To compare the relationship between the positive rate of serum AFP in patients with gastric cancer(ie,AFPGC patients vs non-AFPGC patients)and various clinical characteristics and pathological features,and to observe AFP,these clinical or pathological factors’influence on patients’ prognosis.The TNM staging of gastric cancer patients adopts the Union for International Cancer Control/American Joint Committee on Cancer(UICC/AJCC)Gastric Cancer TNM Staging Standard(2010).SPSS 20.0 statistical software was applied for statistical analysis of the data.The significance test of count data was performed using X2 test or Fisher exact test.Survival analysis was performed using Kaplan-Meier method and log-rank significant test.Multivariate analysis was conducted by using Cox proportional hazards model.Two-sided test,P<0.05 was fully considered to be statistically significant.ResultsAmong 139 cases of included gastric cancer,16 cases(11.5%)were AFP-producing gastric cancer(AFPGC)patients.Compared with AFP-negative(non-AFPGC)group,AFPGC patients are prone to have distant organ metastasis(57.1%vs26.5%,P=0.043),particularly the liver and abdominal metastasis accounted for 79.4%(27/34).Patients who distant organ metastasis in the abdominal or liver are all accompanied by peripheral lymph node metastasis,so we speculate that the pathways of peritoneal and hepatic metastases in patients with gastric cancer are metastasized by peripheral lymph nodes,and AFPGC patients are more likely to occur in stomach bottom and cardia in the tumor location(43.8%vs12.8%,P=0.006),later clinical stage(57.1%vs26.6%,P=0.018),and younger patients(≤60 years)in age(56.3%vs30.9%,P=0.044).However,there were no significant differences in gender,tumor size,depth of invasion,degree of differentiation,surgical procedures,and H.pylori infection between two groups.Kaplan-Meier survival analysis showed that the median overall survival(mOS)of patients with AFPGC was significant less than that of non-AFPGC patients(40 months vs 55 months,P = 0.042)and the mOS of patients that age≤60 years was significant less than that of patients that age>60 years(39months vs 42 months,P=0.024).Multivariate analysis have suggested that age is an independent risk factor of gastric cancer patients(P<0.05).ConclusionAFPGC patients have a worse prognosis,and age is an independent factor affecting the survival of patients,which is more prone to have higher incidence rates in younger age(≤60 years)and in the gastric cardia location.So young patients need routine serum AFP testing and clinical doctors should pay more attention to gastric cardia site when gastroscopy.AFPGC patients are more likely to metastasize to the liver and peritoneal space through peripheral lymph nodes,suggesting that a more severe intraoperative lymph node dissection is needed.