Primitive Neuroectodermal Tumor Of The Right Kidney With Thrombus Of The Inferior Vena Cava:Analysis Of 1 Case And Literature Review

Objective: Renal primitive neuroectodermal tumor is a rare,aggressive,highly malignant tumor,classified as Ewing's family related to tumor,cells show drab little circular,EWS gene and EST gene chromosome translocation is leading the cancer gene fusion,the patients often diagnosed with venous tumor thrombus or distant metastasis in the first time.Until now,how to treat renal primitive neuroectodermal tumor is not standardized,this paper reports a case of a primitive neuralectodermal tumor of right kidney with the thrombus of inferior vena cava and review the related literature at home and abroad.We explore the clinical features,radiological features and pathological characteristics,such as immune phenotype,analysis the diagnosis and treatment of the disease to provide guidance for clinic.Methods: We analyze the clinical symptoms,clinical signs,laboratory examinations,imaging findings,treatment plans and postoperative pathological results of a patient with right renal primitive neuroectodermal tumor with the thrombus of inferior vena cava,and combins the relevant literatures at home and abroad in recent years to analyze and summarize the clinical situation to form a relatively complete treatment plan.Results: No obvious abnormality was found in the laboratory examination of the patient.CT and MRI examination showed that the tumor was cystic and solid with clear boundary and accompanied by filling defect of right renal vein and inferior vena cava.The patient underwent radical nephrectomy of the right kidney and removal of the inferior vena cava tumor thrombus.Postoperative pathology showed that under light microscope,the tumor cells were round,oval or polygonal,some of them were giant tumor cells,with unclear cell boundaries and large nucleoplasmic ratio.Tumor cells were clustered and separated by fibrous connective tissue into nests,cords or clusters,forming pseudochrysanthemum clusters or Homer-Wright chrysanthemum clusters.Immunohistochemical markers: CD99,Fli-1,Ini-1 and Ki-67 were positive.The pathologic finding was small round blue cell tumor,consistent with primary neuroectodermal malignancy.The patient recovered satisfactorily after surgery and discharged 1 week later.Two months after the surgery,the tumor metastasis was found in the double lungs and the 5th lumbar vertebra,six cycles of chemotherapy(ifosfamide + epirubicin + cisplatin + anrotinib)were further performed.After two cycles of chemotherapy,the reexamination had already achieved partial clinical remission(PR).And after 6 cycles of chemotherapy,reexamination basically achieved clinical complete remission.Conclusion: Pain,gross hematuria and abdominal mass can be found in the clinical symptoms of primary neuroectodermal tumors of the kidney.Early diagnosis is difficult,the diagnosis mainly depends on pathological examination,immunohistochemistry and molecular genetics can be clear;Imaging examination is nonspecific but helpful for clinical staging.Renal primitive neuroectodermal tumor is a highly aggressive,metastatic and relapsing malignant tumor.The survival of patients can be improved by comprehensive treatment including surgery,chemotherapy,radiotherapy and biological targeting.For the treatment of complicated inferior vena cava tumor thrombus,the survival time of patients can be significantly prolonged if the tumor thrombus can be completely removed by surgery.