Clinicopathology、Immunohistochemestry And FISH Of Peripheral Primitive Neuroectodermal Tumor Family

Purpose:To study the diagnosis, differential diagnosis, immunohistochemical expression characteristics, specific chrommosome ectopic and prognosis of peripheral primitive neuroectodermal tumor (PNET) family.Methods:1) Thirty-four cases of PNET family were retrospectively collected which were treated by surgery in zhong shan hospital from 2006 to 2013. All of them were reviewed by 2 chief physicians.2) representative tumor tissue were selected and tissue microarrays were maked.3) Immunohistochemistry of 48 antibodies including CD99,Vim、NSE、CD117、 Clusterin、WT-1、TTF-1、CD138、P53、CD56、CD57、CD10、ALK(P80)、D2-40、 CEA、S100、SYN、K167、HMB45、CKp、Des、CD44、Myogenin、EMA、PLAP、 OPN、MDM2、IL2、FOXM1、GNAT3、ERCC-1、GS、HSP70、Survivi、CyclinD1、 HBME-1、CK5/6、NF、CHG、GFAP、TDT、β-tubulin、β-catenin、VS38C、LCA、 P63、bcl-2 were performed in the tissue microarrays.4) FISH was utilized to analyze the EWSR1 gene with a dual color probe (Vysis company) in all the cases and analyze the EML4-ALK gene in the 3 case who showed positive of ALK(D5F3).5) All the patients were followed up by telephone and letter.6) Combined with clinical data, IHC ang follow up result,used SPSS for statistic analysis.Result:1) A total of 34 patients suffered from PNET family tumors with median age of 25 years, aged from 10 to 85. Among them 21 were men and 13 were women. The tumors distributed in limbs and joints (6)、soft tissue(8), chest and lung (5), kidneys(5), abdominal cavity (1)and retroperitoneal (1)and other parts.2) With small round cell morphology as the mainly feature, the tumor cells had round or oval nucleus, stained chromatin condensation and small nucleoli. Cells were mostly arranged in lobulated or flake interlobular with fibrous connective tissue ranged intervally. Most of tumors may formed the spacifically Homer-Wright rosettes, which3) center was nerve fiber material, rather than vessels. Hemorrhaged and necrosis of the tumor were common.4) Immunohistochemically,33 cases were strong positive for CD99(97%),34 cases were positive for NSE (100%),34 cases were positive for VIM(100%).29 cases were positive for Clusterin (85%),32 cases were positive for β-catenin (94%),27 cases were positive for CD11(79%). In addition,5 cases were express of WT-1(15%),2 cases were express of TTF-1(6%),30 cases were expressed of VS38C(88%).The postive rate of CD138 was 38%, ALK(D5F3) was 38%.5) EWSR1 gene translocation was found in 30 of 34 cases by FISH. EML4-ALK gene translocation was detected in the cases showed strongly positive of ALK (D5F3) Immunohistochemically by FISH, and the results were negative.5) Clinical follow-up were available for 26 patients(26/34,76%),and 18 of them were die.1-year survival rate was 68%,2-year survival rate 56%,5-year survival rate was 6%. Prognosis of PNET was better than ES and Askin (P=0.014), there was a good trend about the prognosis of patients younger than 19 years old and female patients, but relations with other indicators of prognosis were unclear.Conclusion:PNET is was a kind of highly malignant soft tissue sarcoma which occurs in young people, CD99 was the classic diagnostic marker. Clusterin, β-catenin, CD117 always highly expressed which can be used as a diagnostic marker. WT-1, TTF-1, VS38C, CD138 were occasionally express ed, which may interfered with the pathological diagnosis. Interphase FISH can be reliably applied to paraffin-embedded tissues for molecular diagnosis of PNET family.