their classification is distinguished in angiosarcomas , leiomyosarcomas , fibrosarcomas , epitheloid hemangioendotheliomas , malignant fibrous histiocytomas and undifferentiated embryonal sarcomas of the liver ( uesl ) . undifferentiated embryonal sarcoma of the liver ( uesl ) is of mesenchymal origin , with increased degree of malignancy . a thorough search through medline ( mesh : undifferentiated embryonal sarcomas liver [ all fields ] and ( " adult " [ mesh terms ] or " adult " [ all fields ] ) brings out a limited number of papers that account for 68 cases , dating from 1955 to 2007 . uesl as a clinical entity was first reported by stocker and ishak,1 in 1978 as a report of 31 cases . today it is considered mostly a childhood finding , ranging to ages from 6 to 10 years . when it comes to adults , its prevalence is lower , with approximately ten cases of primary uesl reported so far . the clinical treatment and strategy , for this tumor to be followed remains ambiguous , for adult patients . therefore , we present an adult case of uesl that has been referred to our center . a 29-year old female patient presented with severe intermittent epigastric pain that was irradiating to the right hypochondrium . she presented with no signs of liver deficiency , and in addition no jaundice , spider naevi or palmar erythema were present . in the past , she had been subjected to surgery for the removal of ovarian cysts in 2002 and 2003 . scan revealed the presence of a voluminous space - occupying lesion , located to the right lobe of the liver . it was of low density and after the intravenous infusion of contrast , late enhancement was being presented . additional magnetic resonance imaging showed the lesion mainly hypointense on t1 with hyperintensed foci that were ascribed to points of hemorrhage . on t2 , moreover , it was positive for neoplastic necrosis . after a multi - disciplinary team ( mdt ) meeting , it was decided to proceed with a right trisectonectomy . since the flr was considered insufficient for direct operation it was decided to perform embolization of the right portal vein , along with selective embolization of the portal branch to segment iv . four weeks later , a new ct volumetry of the liver revealed hyperplastic growth in size of the flr from 32% to 45% , and it was decided to proceed with a right trisectionectomy ( fig . 1 ) . the operation was a straightforward right trisectionectomy , a bilateral subcostal incision was performed and skeletonization resection of the hepatoduodenal ligament , including dissection of the regional lymph nodes , was performed from the duodenum to the liver . then , at a more superior level , the right portal vein was divided , and was closed with a continuous suture . the right liver was mobilized and the right and middle hepatic veins were dissected and ligated with an endogia , and right trisectionectomy was performed . operation time was about 4 hours and total blood lose was 450 ml . no red blood cells were transfused , either during the operation or postoperative . the post - operative period was uneventful and the patient was discharged at the 11 postoperative day . from the pathology report the tumor was positive for malignancy of mesenchymal character possibly vascular derived . the tumor was subcapsular , sharply demarcated from the surrounding liver parenchyma , solid , measured 18 cm in diameter , with grey - white glistening cut surface altering with cystic gelatinous areas and areas of hemorrhage and necrosis . microscopically there were large areas of necrosis . in the viable areas the tumor cells were ovoid or spindle - shaped , with ill - defined outlines , often pleiomorphic , bizarre , with irregular , hyperchromatic nuclei , numerous mitoses and sometimes giant cells ( figs . 2 and 3 ) . multiple eosinophilic globules , periodic acid  schiff ( pas)-positive and diastase resistant were seen . the tumor cells arranged loosely in a myxoid matrix or more compactly in a fibrous stroma . at the periphery of the tumor trapped bile ducts and hepatocytes were detected . by immunohistochemistry the tumor cells were positive in vimentin , ( mesenchymal marker ) and weakly positive in desmin , a specific marker for myogenic differentiation . all of the following immunohistochemical markers were negative : s-100 protein and cd 57 ( markers for schwannian differentiation ) , sarcomeric actin , myogenin , laminin , collagen iv ( peripheral nerve sheeth tumor markers ) , c - kit ( marker for gist ) , melan a and hmb 45 ( melanocytic markers ) , cd 34 ( endothelial marker ) , ema and ae1/ae3 ( epithelial markers ) , afp and heppar1 ( hepatocytic markers ) . the diagnosis of an undifferentiated embryonal sarcoma of the liver ( uesl ) was made . the patient was referred to the oncologists for adjuvant chemotherapy , and thirty cycles of combination of cyclophosphamide , cisplatin and doxorubicin were administered . follow up imaging six months after the operation revealed compensating left lobe hyperplasia and caudate lobe , homogenous liver parenchyma and absence of lymph nodes of pathological size . twelve months after the operation a new ct scan revealed recurrence of the tumor to the liver . after a new mdt meeting , it was decided to continue the chemotherapy . a new ct scan 6 months after revealed total regression of the recurrence . the patient remained disease free for a few months when a new recurrence to the liver and metastasis to spine was presented . a written consent on the use of the material needed for this case report was being obtained by the family of the patient , following the directives of the university ethics committee , according to the 1975 declaration of helsinki . by now , uesl is considered a rare entity for adults . in child population , medical literature so far reports no more than 150 cases.2 uesl is listed fourth in the prevalence of primary hepatic tumors . under the age of 18 years , the most common primary hepatic neoplasm is hepatoblastoma , and then comes hemangiendothelioma and hepatocellular carcinoma.3 it has to be added that there is no gender predominance , and it is evident a preference for the right hepatic lobe location.4 the histogenesis of uesl remains unknown.5 despite its name there is not any resemblance with embyonal liver . the diffuse pattern of infiltration that tends to spare bile ducts provides the resemblance to mesenchymal hamartoma , which is now established as a precursor to the malignancy . as a distinguished clinical pathology to the same report , only 6 out of 31 patients remained disease free after the surgical resection . bisogno et al.,6 the soft tissue sarcoma italian and german cooperative groups presented a group of 4 patients who underwent combined treatment of surgical resection and then adjuvant therapy . total remission was achieved for all of them , over a follow up from 5 to 10.9 years . the adjuvant treatment received by this group was a combination of vincristine , actinomycin , fosfamide and doxorubicine , as first line treatment . a disease - free follow up was also being described by kim et al.7 in a group of three children that underwent the same treatment of surgical resection and adjuvant therapy mentioned above , they had no sign of tumor recurrence over a time of 40 to 60 months.7 lenze et al.8 reviewed reports from 1995 to 2007 , pointing out a significant predominance in survival if the treatment strategy included the combination of surgical resection and adjuvant chemotherapy . he also showed the absence of a study analyzing uesl treatment strategy and prognosis , not even in children . the report is a retrospective study comparing groups that have been treated with total surgical excision without adjuvant therapy , total surgical excision with adjuvant therapy and non - complete surgical excision with adjuvant chemotherapy . their findings are clear ; combining complete excision with adjuvant chemotherapy strongly dictates better prognosis and longer survival without complications . align with this result is the outcome of almogy et al.9 in this report , with statistic findings from a single center , the superiority of adjuvant therapy versus no chemotherapy at all , is evident . to this conclusion has to be added the fact that these kinds of tumors augment their size without special signs or characteristic symptoms . when they are found , their volume is too large thus adjuvant therapy seems proper and rational . in a single report , garca  bonaf et al.10 highlight the value of the recognition of the cytologic features , through fine needle aspiration , of this type of tumor , in order to obtain a more targeted strategy on neoadjuvant therapy . it is also important to differentiate the tumor from a benign entity , when the imaging does not provide sufficient evidence.11 taking this observation even further , kim et al.7 along with the single center results reported by ismail et al.,12 showed that neo - adjuvant therapy could lead to a diminished tumor size , making possible a complete surgical excision . even if the tumor is excised in an oncological accepted surgical excision , without remnants ( r0 resection ) , local recurrence along with metastases is not an uncommon finding.13 repeated operations may be needed.14 since there is no special serum marker that indicating recurrence , additional periodic imaging control is necessary post - operational.15 our patient presented no augmented afp , or any signs of cirrhosis , thus diminishing the possibility of a hepatocellular carcinoma case . the absence though of specific findings from the needle biopsy did not permit the application of neo - adjuvant therapy to our strategy . combining all of the above , the recent literature and our center 's experience , and since the diagnosis was obtained after operation , the patient was treated with 30 cycles of adjuvant therapy . nevertheless , recurrence was aggressive , and the patient passed away 28 months after the operation .
undifferentiated embryonal sarcoma of the liver ( uesl ) is a tumor highly malignant , of mesenchymal origin . 
 it is a rare finding in adults , though less rare in children . 
 the strategy to be followed and the therapeutic targets to be reached for this tumor , in adult cases , remain ambiguous and controversial . 
 herein we report the case of a 29 year old female patient with a massive uesl and we describe our therapeutic approach . 
 a 29 year - old female patient was referred to our center with severe intermittent epigastric pain and fever due to a voluminous liver tumor : needle biopsy was of no specific findings and surgical excision was decided . 
 right portal vein embolization and selective embolization of the segment 's iv branch was performed in order to achieve adequate future liver remnant ( flr ) . 
 right trisectonectomy was then performed , with uneventful post operative period and the patient was discharged at the 11th post operative day . 
 uesl is a rare tumor that needs aggressive surgical approach and multidisciplinary team management is of paramount importance .