Researches And Differential Diagnosis Of Ewing Sarcoma Of Bone On Imaging Features

Part One Imaging research of Ewing sarcoma of boneObjective: Ewing sarcoma of bone is the second most common primary osseous malignancy in children and adolescents,second only to osteosarcoma,Because there is no characteristic clinical symptoms,so it is often difficult to make an accurate diagnosis before treatment.This part of the study retrospectively analyzed and summarized the clinical and imaging features of Ewing sarcoma of bone,hoping to find valuable features for clinical diagnosis.Methods: From January 2004 to January 2020,25 cases of Ewing sarcoma of bone confirmed by histopathology were selected as the study objectin in the third hospital of hebei medical university.Among them,15 cases were male,1 0 cases was female,male: female = 1.5:1.Among 25 cases of Ewing sarcoma of bone,20 cases were examined by X-ray,23 cases by CT and 23 cases by MRI.17 cases were examined by X-ray,CT and MRI,and 8 cases by X-ray or CT or MRI.To Induction and study the clinical and imaging features of Ewing sarcoma of bone.Results: The age of onset ranged from 1.3 to 27 years,and the median age was 12 years.The peak age was 11-20 years(44%).23 cases(92%)were single focus and 2 cases were multiple focus.Of the 23 cases,10 were located in the long bone,4 in the ilium,1 in the calcaneus,1 in the thoracic spine,1 in the lumbar spine,3 in the sacrum,2 in the scapula,and 1 in the cervical spine.There were 6 cases in the long bone shaft,four cases were located in the epiphysis of the long diaphysis.1.Features of X-ray 、CT changes in a single lesion 1)Most of ebony’s sarcomas were lytic bone destruction(14/23 cases,60.9%)and mixed bone destruction(7/23 cases,34.8%).Sclerotic bone destruction was rare(1/23 cases,4.3%).2)The most common form of bone destruction was mouth-eaten or permeative bone destruction(14/23 cases,60.9%).The expansion of 13% of the focus is rare.residual bone crest(21.8%)is rare.Pathologic fractures due to trauma occurred in some cases(3/23 cases,13%).3)Periosteal reaction:Periosteum reaction was found in some patients(9/23 cases,39.1%).In some cases of Ewing sarcoma of bone,Vertical hair periosteum reaction(1/23 cases,4.3%),Onion skin-like periosteum reaction(5/23 cases,21.7%),"sun-shine periosteum reaction"(3/23 cases,13%).Endoosseous reaction(3/23 cases,13%),and it was mixed with onion skin-like periosteum.2.On MRI,Normal bone marrow was replaced by tumor in 100% of the patients with single focus,Most of the lesions(19/23 cases,90.3%)showed low signal on TWI1 and high signal on TWI2.Soft tissue mass around the focus was formed in 90.5% of the patients,Cystic changes in soft tissue masses(1/21 cases,4.8%)were rare,There was obvious edema of the surrounding soft tissues in a few cases(5/21 cases,23.8%).The “concentric circle sign” was more common in all periosteal reactions(23.8%).3.There were 2 cases with multiple lesions,1 case located in the right ilium and right Ischia.One case was located in the right tibia fibula and the right calcaneus.There was no significant difference between the two cases and the single case.Conclusions: 1.The peak age of Ewing sarcoma of bone was from 11 to 20 years(44%).2.the single focus of Ewing sarcoma of bone was more common in the long bone shaft(26%),osteolytic bone destruction(56.5%)and mixed bone destruction(39.1%).No tumor bone was found.The most common form of bone destruction was mouth-eaten or permeative bone destruction(60.9%).The expansion of 13% of the focus is rare.residual bone crest(21.8%)is rare.Pathologic fractures due to trauma occurred in some cases(13%),and "Endoperiosteum reaction"(2/23 cases,8.9%)are important to the diagnosis of Ewing sarcoma of bone.3.On MRI,Normal bone marrow was replaced by tumor in 100% of the patients with single focus,Most of the lesions(90.3%)showed low signal on TWI1 and high signal on TWI2.Soft tissue mass around the focus was formed in 90.5% of the patients,and it shaows mild bone destruction with large soft tissue mass.Cystic changes in soft tissue masses(4.8%)were rare,There was obvious edema of the surrounding soft tissues in a few cases(23.8%).The “concentric circle sign” was more common in all periosteal reactions(23.8%).4.There were 2 cases with multiple lesions,1 case located in the right ilium and right Ischia.One case was located in the right tibia fibula and the right calcaneus,There is an intimal reaction.There was no significant difference between the two cases and the single case.Part Two The differential diagnosis between Ewing sarcoma of bone and other easily confused bone diseasesObjective: Clinically,Ewing sarcoma of bone is not easily distinguished from Acute osteomyelitis,Eosinophilic granuloma,and Osteosarcoma,of which the ages and prone sites are similar.Therefore,in the second part of this article,we attempt to distinguish Ewing sarcoma of bone from the latter three bone diseases by the quantized image sign.Methods: Patients with Ewing sarcoma of bone,Acute osteomyelitis,Eosinophilic granuloma,and Osteosarcoma confirmed by histopathological examination which were admitted to the third hospital of hebei medical university from January 2004 to January 2020 were selected as the study subjects.The research method of the 25 cases of Ewing sarcoma of bone was in the first part of the study;There were 27 cases of Acute osteomyelitis,of which 25 patients was examined by X-ray,22 cases by CT,and 26 cases by MRI.There were 10 cases of eosinophilic granuloma,of which 7 patients was examined by X-ray,8 cases by CT,and 5 cases by MRI.There were 128 cases of Osteosarcoma,of which 85 patients was examined by X-ray,91 cases by CT,and 105 cases by MRI.The imaging signs of bone Ewing sarcoma of bone that were distinguished and compared with the above three diseases: lesion location,Types of lesion destruction,morphology of bone cortical destruction,periosteum reaction,residual bone crest,tumor bone,and expansion changes.MRI lesion signal,soft tissue mass,cystic change in mass,soft tissue edema In addition,Ewing sarcoma of bone and Acute osteomyelitis were identified separately: serpentine channel,penumbra sign,fatty droplets,abscess.Results: 1 Comparison of age at onset The peak age in patients with Ewing sarcoma of bone was between 11 and 20 years(44%),with a median age of 12 years;the peak age in the acute Osteomyelitis group was between 1 and 10 years(52%),with a median age of 9 years;The peak incidence in the Eosinophilic granuloma group was 1 to 10 years old(80%),with a median age of 9 years.The peak incidence in the osteosarcoma group was 11 to 20 years(61%),with a median age of 19 years.2 Comparison of disease sites 2.1 The four bone diseases in this group are more common in long bones;From least to most,Ewing sarcoma of bone(44%),Acute osteomyelitis(70%),Eosinophilic granuloma(81.5%),Eosinophilic granuloma(88.2%).Acute osteomyelitis and Osteosarcoma were more common in long bones than Ewing sarcoma of bone respectively,and there was statistically significant difference between the two groups(P <0.05).The difference between eosinophilic granuloma and Ewing sarcoma of bone was not statistically significant(P> 0.05).2.2 In long bone lesions,Acute osteomyelitis was more common in the metaphysis(59.1%),and Ewing sarcoma of bone was more common in Long bone shaft(63.6%),but there was no statisticant significant difference between the two groups(P> 0.05).Eosinophilic granuloma occurred in long bones(71.4%),There was no significant difference compared with Ewing sarcoma of bone(P> 0.05).This group of Osteosarcomas occurred in the metaphysis of long bones(87%),There was a significant difference compared with Ewing sarcoma of bone(P <0.001).3 Comparison of imaging characteristics 3.1 Identification and comparison of Ewing sarcoma of bone and Acute osteomyelitis: Ewing sarcoma of bone(4/25 cases,16%)showed swelling changes in the bone destruction area,and 27 cases of Acute osteomyelitis had no swelling changes,and there was a significant difference between two groups(P = 0.039).On MRI images,there are 91.3%(21/23 cases)of Ewing sarcoma of bone lesions had formation of soft tissue mass,and 26 cases of Acute osteomyelitis had no soft tissue mass,and there was a significant difference between two groups(P <0.001).Some cases of Acute osteomyelitis had intraosseous or extraosseous abscesses(13/26 cases,50%),"serpentine channel"(7/26 cases,26.9%),"penumbra sign"(6/26 cases,23.1%),"Fatty droplets"(7/26 cases,26.9%),but Ewing sarcoma of bone did not show these four specific imaging signs,and there was a significant difference between two groups(P <0.05).There was obvious edema around the lesions of Ewing’s sarcoma of bone(6/23 cases,26.1%),and Acute osteomyelitis(22/26 cases,84.6%),there was a significant difference between two groups(P <0.001).3.2 Comparison of Ewing sarcoma of bone and Eosinophilic granuloma Eosinophilic granulomatous lesions(6/9 cases,66.7%)were more common than Ewing sarcoma of bone lesions(4/25 cases,16%),Soft tissue masses surrounding Eosinophilic granuloma(1/5 cases,20%)were less common than Ewing sarcoma of bone(21/23 cases,93.1%),Eosinophilic granuloma(4/5 cases,80%)was more common than Ewing sarcoma of bone(6/23 cases,26.1%),and there was a significant difference compared with Ewing sarcoma of bone(P <0.05).3.3 Comparison of Ewing sarcoma of bone and osteosarcoma Osteosarcoma was characterized by osteoblastic destruction(60/117 cases,51.3%),geomorphic bone destruction(87/117 cases,74.4%),tumor of bone(58/117 cases,49.6%),periosteum reaction(86/117 cases,73.5%),and Codman triangle(50/117 cases,42.7%).Ewing sarcoma of bone was characterized by osteoblastic bone destruction(1/25 cases,4.0%),getinoplastic bone destruction(9/25 cases,36%),There is no tumor bone formation,periosteum reaction(10/25 cases,16%),and Codman triangle(2/25 cases,8.7%),The differences in the four imaging changes were significant significant(P<0.05).Residual bone crest in the lesion of osteosarcoma(1 case / 117.0.9%)and endoosseous reaction(1 case / 117.0.9%),Residual bone crest in the lesion of Ewing sarcoma of bone(1 case / 117.0.9%)and endoosseous reaction(1 case / 117.0.9%),The differences in the two imaging changes were statistically significant(P<0.001).Osteosarcoma(59/105 cases,56.2%)showed hypointense on T1 WI and mixed high signal on T2 WI,this is more common be seen than Ewing sarcoma of bone(223 cases,8.8%),there was a significant difference compared with Ewing sarcoma of bone(P < 0.05).Conclusions: 1.The peak onset age of Acute osteomyelitis is 1 to 10 years(52%),which is younger than Ewing sarcoma of bone;The Acute osteomyelitis was more often occurred in the metaphysis(59.1%),which was different from Ewing sarcoma of bone.Acute osteomyelitis without focal expansion.There is no soft tissue mass formation in the focal area of acute osteomyelitis.Edema is more obvious than Ewing sarcoma of bone.On MRI,100% of the lesions had no soft tissue mass formation.Some of the cases presented with intrauterine or intrauterine abscess(50%),"serpentine channel"(26.9%)," penumbra sign"(23.1%),and "Fatty droplets"(26.9%),but Ewing sarcoma of bone did not show these four specific MRI imaging signs.2.The peak onset age of Eosinophilic granuloma was 1 to 10 years old(52%),which was younger than Ewing sarcoma of bone.Eosinophilic granuloma(66.7%)is more common expander than Ewing sarcoma of bone(16%).Eosinophilic granuloma(93.1%)showed more edema in the surrounding soft tissue than Ewing sarcoma of bone(26.1%).3.The peak onset age of Osteosarcoma was 10 to 20 years old(61%),which was similar to the Ewing sarcoma of bone;The Osteosarcomas(87%)occurred in the metaphysis of long bones.The incidence of Osteosarcoma was higher than Ewing’s sarcoma:Osteogenic bone destruction(51.3%),geomorphic bone destruction(74.4%),tumor bone formation(49.6%),periosteum reaction(73.5%),Codman triangle(42.7%).The lesions of Osteosarcoma(56.2%)showed low signal on T1 WI and mixed high signal on T2 WI.The incidence of osteosarcoma was lower than Ewing’s sarcoma: Residual bone crest(0.9%)and Endoosseous reaction(10.9%)were found in the lesions of osteosarcoma."Endoosseous reaction" is important diagnostic value in differentiating osteosarcoma from Ewing sarcoma of bone.