The Study On Clinical Characteristic And Expression Of FASN In Pediatric YST

Objective:To analyse the clinical characteristics of pediatric YST and investigate the differences of diagnosis and treatment between gonadal and extragonadal YST.Meanwhile to study the expression and significance of FASN in pediatric YST.Methods:26 clinical datas of pediatric YSTs were analyzed by comparing the differences of clinical manifestation, diagnosis and treatment between gonadal and extragonadal ones. These 26 yolk sac tumors and another 14 cases of IMT,1 case of EC,12 case of associated normal tissues were studied with immunohistochemical detection.Results:1.There was no statistical difference in the age distribution and average age between gonadal and extragonadal YST(P>0.05).2.A11 patients in the group were examined by preoperative color ultrasonography. Except the testicle YST and chest YST, the rest cases were also scaned enhanced CT or MRI. There was no difference in the imaging findings between gonadal and extragonadal YST.3.There was no statistical difference in preoperative Serum AFP Lev- els(P>0.05). But postoperative serum AFP levels of gonadal YST could decrease more significantly(P<0.05).4.All patients in the group were treated by radical surgery and postoperative chemotherapy. There was no statistical difference in the choice of intraoperative lymph node dissection between gonadal and extragonadal YST(P>0.05). Patients with extragonadal YST were more inclined to receive preoperative chemotherapy than gonadal ones(P<0.05).5.There was a case of extragonadal YST recuring postoperatively, while all patients with gonadal YST had not recured in the follow-up. There was no statistical difference in recurrence rate between the two(P>0.05).6.Positive expression rate of FASN was 73% in YST,28% in IMT, none in EC and 16% in normal tissues. Expression of FASN was higher in extragonadal YST(100%) than in gonadal ones(56%). High expression was also observed in lymphaden or distant metastasis(100%), while was less prominent in the cases without metastasis(61%). The expression rate of FASN in YST were positively correlated with clinical stages. Above differences were statistically significant(P<0.05). There was no statistical difference between yolk sac tumors without chemotherapy and ones with chemotherapy(P>0.05).Conclusions:YST had an early onset and was concealed, extragonadal of which was more aggressive. There were some differences in clinical characteristic, diagnosis and treatment between gonadal and extragonadal YST. The expression of FASN may provide a reference for the diagnosis and treatment of pediatric YST.