The Prognostic Value Of Serum Alpha Fetoprotein's Biological Half-life In Tumor Recurrence After Liver Transplantation For Hepatocellular Carcinoma

Hepatocellular carcinoma(HCC)is one of the most common cancer in the world and account for an estimated 500,000 new patients.HCC causes one million deaths in China annually,the mortality rate of HCC is 42%.The cardinal curative therapy is surgical resection,however,many patients have the conditions such as liver cirrhosis, poor liver function,special location,which ususlly restrict surgical resection.The progress of orthotopic liver transplantation(OLT)make it possible for those patients' therapy.Recently,HCC has become one of the indications for liver transplantation.Liver transplantation(LT)can remove whole liver included the tumor lession and the soil for HCC growth.LT is benefit to the liver function's recovery and improve the live quality.However,the higher tumor recurrence after the liver transplantation causes lower survival of recipients.Especially in the early times,the operation were carried out for mang patients which were not suitable liver resection.The liver transplantation once became the contraindication because the the higher tumor recurrence and lower survival of recipients.With the development of the LT technique, renew of the anti-immune medicines,and the accumulation of the experiences of multi-centers,strict inclusion criteria applied for selecting HCC recipients,such Milan and UCSF.Recently,it reports that HCC recurrence rate of different transplantation centers is about 25%～67%,the tumor recurrence has become the most important issue in liver transplantation field,and need to resolve.So it is very important to look after for prognostic index to predict the HCC's recurrence,which is significant to the patient long-term prognosis. Alpha fetoprotein(AFP)remains a most useful tumor marker in screening HCC patients,because the serum AFP is elevated in HCC sensitivity,which is useful in early diagnosis,estimate curative effect and prognosis of HCC.More than 70%of HCC patients have a high serum concentration of AFP because of the tumor excretion. After liver transplantation,most time serum AFP concentration will become normal post-operation.Furthermore the persistent high AFP levels or the long time that serum AFP reduces to normal range may indicates the intra-or extrahepatic cancer spread and be associated with poor prognosis.However the serum AFP after the liver transplantation is ususlly affected by the pre-operation AFP levels and liver cirrhosis, so the value of the AFP reduces to normal range or not is knocked down to forecast the HCC recurrence.It reports that the serum AFP biological half life after the liver transplantation will not be affected by the pre-operation AFP levels and liver cirrhosis, this study apply the serum AFP's biological half-life to forecast the HCC recurrence in order to discuss the prognostic value of AFP's biological half-life in tumor recurrence after liver transplantation for hepatocellular carcinoma to improve the patients' prognosis.[Materials and methods]:1.Clinic materials:From Jan.2005 to Dec.2005,the liver transplantation department in general hospital of armed police force,carried out 58 liver transplantation operations for 58 patients whose preoperative serum AFP are positive (AFP＞25 ng/ml).There are 51 male patients and 7 female patients with the average age of 51(34-71years);included 47 patients who have HBV hepatocirrhosis with primary liver carcinoma and 5 patients have HCV hepatocirrhosis with primary liver carcinoma.There are 6 patients who were diagnosed as alcoholic hepatocirrhosis with primary liver carcinoma.There are 9 patients who received trans-arterial chemotherapy and embolization(TACE)and 15 patients received the surgical resection before operation.There are 13 patients have portal vein cancer embolus,and 22 patients have the cancer diameter beyond 5cm.2.Methods (1)Follow up 58 patients,monitor the serum AFP,ultrasonic,Chest X-ray, ECT,and study the HCC recurrence of the patients.(2)According to the the follow-up result,58 patients were devided into recurrence group and non-recurrence group,compare the differerces of two groups' AFP T_1/2.(3)Choose one serum AFP T_1/2point which the yonden's index is the largest,and the serum AFP T_1/2will be used to predict the HCC recurrence,the point was name for P.(4)Accordiong to the AFP T_1/2,58 patients are devided into two groups.One group AFP T_1/2＜P,Second group AFP T_1/2≥P,investigate the differences of the HCC recurrence of two groups.(5)According to the the postoperative dynamic changes of serum AFP,patients are divided into three groups,group A(post-LT AFP levels decreased under 25 ng/ml within 1 month),group B(post-LT AFP levels decreased under 25 ng/ml within 2 months)and group C(post-LT AFP levels never decreased under 25 ng/ml).Analyze the differences of the recurrence rate of three groups,in order to estimate the value of dynamic changes of serum AFP to the HCC recurrence after liver transplantation.[Results]:(1)The biological half-life time of serum AFP of recurrence group(8.92±4.41d)is obvious longer than the non-recurrence group(5.09±2.42d).the differences between two groups were significant.(2)The group which biological half-life of serum AFP is below 6.5 has lower HCC recurrence(25.0%),and the prognosis is better;while the group which biological half-life of serum AFP is more than 6.5 days has higher recurrence rate(77.8%),the recurrence rates between two groups were significantly different.(3)According to the the postoperative dynamic changes of serum AFP,patients divided into three groups.The recurrence rate in group C(70.6%)was higher than in group A(28.1%)and group B(33.3%),the recurrence rate between group A and group B was not significantly different.[Conclusion]: (1)The postoperative dynamic changes of serum AFP level have close correlation with tumor recurrence,the delay of serum AFP reduces to normal range may predict the higher HCC recurrence.The biological half-life time of serum AFP of recurrence group is obvious longer than the non-recurrence group.(p＜0.01)(2)The biologica half-life of serum AFP is a useful monitor for the prognosis of patients with HCC after liver transplantation.That AFP T_1/2beyond 6.5days indicates higher HCC recurrence and worse prognosis.(3)The serum AFP's biological half-life has higher sensitivity and speciality than the dynamic changes of serum AFP to predict the HCC recurrence.