Analysis Of Imaging Features Of Primary Bone Lymphoma And Its Differentiation From Bone Metastases

Objective:To investigate the imaging manifestations of Primary bone lymphoma(PBL)and to maximize the diagnostic value.The relatively low clinical incidence of primary bone lymphoma also leads to incomplete grasp of the characteristic manifestations of primary bone lymphoma at present,resulting in relatively low diagnostic rate and extremely easy to misdiagnose.The purpose of this study was to study the imaging characteristics of primary bone lymphoma,and to quantitatively analyze the bone metastatic tumor,which accounted for 60% of the first imaging diagnosis of this group of cases,to improve the diagnosis and differential diagnosis of the disease.Research objects and methods:1.A total of 27 cases of primary bone lymphoma were collected.All the patients were confirmed as primary bone lymphoma by pathological histology.In combination with relevant literature and pathological and immunohistochemical results,imaging signs(X-ray,CT,MRI)were analyzed retrospectively and compared.2.54 cases of bone metastases were collected,all of which were pathologically confirmed and primary lesions were found;The case has complete imaging data(X-ray,CT,MR)to analyze the imaging and clinical features.3.The primary bone lymphoma and bone metastases of clinical manifestations and imaging features of contrast analysis,the major identification indicators: patients age,disease area,the type of bone destruction and soft tissue mass,periosteal reaction and pathological fracture,statistical analysis.On the premise of strictly abiding by relevant standards,statistical analysis was carried out by Statistical processing software.The comparison of the rates was mainly carried out by ?2,and a=0.05 was set as the test.The test standard,P < 0.05,has statistical significance.Results:1.The imaging manifestations and clinical features of primary bone lymphoma were analyzed as follows:(1)Lesions: Among the 27 cases,11 cases were located in the spine(40.7%),5 cases in femur(18.5%),2 cases in tibia(7.4%),2 cases in acetabulum(7.4%),2 cases in maxilla(7.4%),2 cases in temporal bone(7.4%),1 cases in sacrum(3.7%),2 cases in occipital(3.7%)and 1 cases in mandible(3.7%).Single lesions were found in 20 cases,accounting for 74%;7 cases had multiple lesions,accounting for 25.9%.(2)Gender and age: there were 17 male patients and 10 female patients,ranging from 31 to 88 years old,with a median age of 55 years old.(3)27 cases were confirmed as non-hodgkin's lymphoma(NHL)through surgical pathological examination or puncture,of which 25 cases were b-cell origin,accounting for 92.6%.T cell source was found in 2 cases,accounting for 7.4%.(4)Of the 27 cases of primary bone lymphoma,23 had X-ray findings,24 had CT and MRI findings.Complete X-ray,CT and MRI results were obtained in 22 cases.Imaging manifestations and characteristics: In this study,the types of bone destruction,periosteal reaction,soft tissue mass and pathological fracture were analyzed.According to the characteristics of bone destruction,X-ray plain film,CT findings:Bone destruction: In this group of cases,the number of cases of osteolysis,mixed type were15 cases,12 cases.The bone destruction was characterized by a series of conditions,such as sieve pores,multiple foci,and mild expansion.15 cases of osteolytic lesion showed expansive bone destruction,trabecular bone was not clear,and cortical continuity was interrupted.12 cases of mixed type showed bone destruction area with peripheral hyperplasia and sclerotic margin.Periosteal reaction: 5 cases had a few periosteal reactions,and the type of bone destruction was osteolytic type.Soft tissue mass: 20 cases of bone destruction around the defect with different sizes of soft tissue mass,its shape is irregular,the edge is not clear,density slightly lower than muscle tissue.X ray plain film showed 3 cases of soft tissue mass was not obvious,CT and MRI examination can be more clearly displayed.In this series of cases,the spinal lesion did not involve the intervertebral disc,occurred in the sacroiliac joint cases did not involve the intervertebral space.MRI manifestations: lesions were long T1 signal,equal or slightly long T2 signal,fat suppression T2 sequence was high signal,lesion margin visible long T1,long T2 signal shadows.The infiltration degree of adjacent bone: T2 signal in adjacent medullary cavity was uneven,the lesion range was wider,the margin was unclear,and the enhancement of the medullary cavity was obviously uneven.Soft tissue mass: soft tissue masses of different sizes were clearly displayed in 20 patients.In this group,11 lesions involving the spine were involved,Some soft tissue signals presented slightly longer T1 and slightly longer T2 signals around the vertebral body,and some compressed the dural sac.The effective sagittal diameter of the spinal canal narrowed significantly and the adjacent spinal cord was significantly compressed,causing corresponding neurological symptoms.In the pathological results of this group of primary bone lymphoma cases,2 cases were t-cell lymphoma,and the imaging findings showed that all the lesions were osteolytic bone destruction,with mild soft tissue masses surrounding the lesions.2.The imaging manifestations and clinical features of bone metastases are analyzed as follows:(1)Lesion site: 41 cases(75.9%),10 cases(18.5%),3 cases(5.6%),1 case of patella(1.9%),1 case of femur(1.9%),1 case of right shoulder(1.9%),and 1 case of humerus(1.9%).There were 19 cases(35.2%)and 35 cases(64.8%).(2)Gender and age: there were 28 male patients and 26 female patients,ranging from 48 to 83 years old,with a median age of 69 years old.(3)The primary lesions were mostly lung cancer,followed by prostate cancer,Breast cancer and liver cancer.(4)Imaging performance and features:X-ray and CT findings:Bone destruction: in this group,there were 36 cases of osteolysis,16 cases of bone sclerosis and 2 cases of mixed type.Thirty-six cases of osteolytic type showed swelling bone destruction,accounting for 55%,showing the destruction of insect-like bone lesions,and the progression of the disease showed extensive bone destruction.The 16 cases of bone sclerosis presented nodular,mottled and patchy high-density shadows in the lesions,mostly in the metastasis of prostate.Only 2 cases presented bone destruction with sclerotia.Periosteum reaction: 1 case(1.9%)had a little periosteum reaction in the area of osteolytic bone destruction,which was very rare.Soft tissue mass: there were 21 cases(39%)with various degrees of soft tissue mass around bone destruction in lesions,with irregular morphology,unclear edges and slightly less density than surrounding muscle tissue.CT can judge the necrosis,cystic degeneration and hemorrhage in soft tissue.Pathological fractures: there were 30 cases(55.6%)with pathological fractures.There were more cases of spine in this group,and vertebral compressibility changes were often associated with the occurrence of vertebral compression changes.Joint space: there were 41 cases of spinal diseases,and the destruction of vertebra showed compression changes.The lesions generally did not cross the intervertebral disc.Involvement of vertebral arch: In 33 cases(61.1%),vertebral arch was involved,and vertebral arch showed varying degrees of bone destruction.Once vertebral pedicle disintegrated,vertebral arch could easily cause spondylolisthesis.(5)MRI findings:Due to the influence of various factors,the signals presented by lesions in different sequences are significantly different.Usually,T1 WI of lesions presents low signals,while T2 WI of lesions presents high signals,equal signals and low signals.Fat suppression T2 WI presented higher signals,and cortical signals showed irregular features,with low signals on edge T1 WI and high signals on T2 WI.The signal in the medullary cavity of the lesion was uneven,and the edge was unclear.The T1 WI sequence presented a low signal,while the T2 WI sequence showed a high signal shadow.MRI showed more clear and direct invasion of nearby soft tissue masses than CT and X-ray.Among the 21 cases,soft tissue masses of different degrees were clearly displayed around the lesions.In this group,there were few soft tissue masses in the early stage of lesions.3.Statistical analysis of the differential comparison between primary bone lymphoma and bone metastatic tumor:(1)age: 67% of primary bone lymphoma patients were > at 50 years old,with a median age of 55 years old;Patients with metastatic tumor were 98% of >50 years old,with a median age of 66 years old.(2)location of the disease: the spinal column is in the majority,with the primary bone lymphoma spinal lesion accounting for 40.7% and the single lesion in the majority;Bone metastatic tumor accounted for 75.9%,the majority of the multiple lesions,P<0.001,the comparison has significant statistical significance.(3)types of bone destruction: osteolytic type was common,with 55.6% of primary bone lymphoma and 66.7% of bone metastases;P>0.05 there is no statistical significance.(4)periosteal reaction: primary bone lymphoma accounted for 25.9%,and bone metastases accounted for 1.9%,P<0.001,they have statistical significance.(5)pathological fractures: 37% were primary bone lymphoma,55.6% were bone metastases,P > 0.05 there is no statistical significance.(6)mass lesion:primary bone lymphoma(74%),bone metastases 39%,P < 0.001,the more statistically significant number of(7)number of lesions: primary bone lymphoma single-shot(74%),bone metastases single-shot 35.2%,P < 0.001,they have statistical significance.(8)Involvement of vertebral arch: primary bone lymphoma(3.7%),bone metastases 61.1%,P < 0.001 they have statistical significance.Conclusion:1.There was no difference in the imaging manifestations of primary bone lymphoma between single and multiple lesions,while there was no difference in the imaging manifestations of T cell type and B cell type primary bone lymphoma.Imaging diagnosis must be combined with X-ray,CT and MRI to improve the accuracy of diagnosis.2.The onset age of primary bone lymphoma and bone metastatic tumor is basically the same,both of which are middle-aged and elderly;In both groups,the most common sites were the spine,and the main focus was osteolytic destruction.3.The possibility of primary bone lymphoma should be considered in clinical diagnosis:single lesions and early lesions have small bone destruction and obvious soft tissue mass,with less periosteal reaction,and bone destruction is dominated by osteolytic destruction.The lesions occurring in the spine are less involved in vertebral arch and intervertebral disc,and the lesions are obviously strengthened after enhancement.