Comparative Study Between Mammography And MRI Imaging Manifestations Of BI-RADS Category 3-5 Breast Microcalcification

Objective: This research is comparing the shape and distribution of Mammography and MRI imaging test result for BI-RADS category 3-5microcalcification,also compares the diagnosis accuracy for both test method,thereby give guide to choosing the most effective diagnosis method for this type of microcalcification,and increasing the diagnose accuracy of early stage breast cancer,as well as provide help for efficient clinical diagnosis method and treatment.Methods: Retrospective analysis the data of 94 cases detected by mammography and breast DCE-MRI examination confirmed BI-RADS category 3-5 microcalcification from March 2015-December 2016 in Fourth Hospital of Hebei Medical University.Analysis and evaluation Mammography and MRI imaging base on the standard of American College of Radiology breast imaging reporting and data system(BI-RADS).Shape and distribution of calcification for Mammography analysis,analyzing MRI image based on BI-RADS-MRI standard by classify lesion to mass-like enhanced and non-mass-like enhanced,analyze the pattern,edge and internal enhanced characteristics of mass-like enhanced,for non-mass-like enhanced,focus on analyzing morphology distribution.By the size of lesions,drafting time-signal intensity curve based on region of interest,also perform comparative analysis corresponding to histopathology result.Do statistics analysis with SPSS 21.Including:(1)Shape and distribution of positive predictive value of BI-RADS category 3-5 microcalcification on Mammography.(2)positive predictive value of BI-RADS category 3,4 and 5 microcalcification.(3)Positive predictive value and result of Dynamic contrast-enhanced MRI corresponding to Mammography.(4)Dynamic contrast-enhanced curve type comparisonbetween benign and malignant lesion.(5)As BI-RADS category 3,4a as high possibility benign standard,BI-RADS category 4b,4c and 5 as high possibility malignant standard,respectively analyze the sensibility,specificity,PPV,NPV and accuracy of the diagnosis result by Mammography and MRI to BI-RADS category 3-5 microcalcification.(6)Analyze the sensibility and specificity of Mammography and MRI test for different type of breast gland.Results:1 Pathology results: Among all 94 cases BI-RADS category 3-5microcalcification,pathology confirmed 84 cases after surgery,malignant lesions 55 cases,pathology result including: 2 cases of breast mucinous adenocarcinoma,12 cases of invasive ductal carcinoma,2 cases of poorly differentiated adenocarcinoma,29 cases of invasive breast cancer,1 case of ductal carcinoma in situ,1 case of cancerous of breast ductal epithelial atypical hyperplasia,1 case of Paget’s disease of the nipple with large ductal carcinoma,1 case of non-invasive ductal carcinoma,2 cases of invasive lobular carcinoma,1 case of cancerous of severe atypical hyperplasia,2 cases of high nuclear grade ductal carcinoma,1 case of high nuclear grade ductal carcinoma with Paget’s disease.Benign lesions 31 cases,pathology result including: 1 case of breast adenosis with epithelial atypical hyperplasia,10 cases of breast adenosis,2 cases of breast adenosis with columnar cell changes and hyperplasia,4 cases of normal glandular tissue,3 cases of breast adenosis with fibrous adipose tissue,5 cases of breast adenosis with duct dilatation,1case of columnar epithelial atypical hyperplasia,1 case of breast duct dilatation with fat necrosis and inflammatory change,1 case of breast adenosis with fibroma,1 case of breast adenosis with calcification.The rest of 8 cases follow up by Mammography test review after 1 year,as well as reviewed again after 3 months,6 months and another year,no obvious change compare to original Mammography test image,thereby concluded to be benign lesions.2 Morphologic features,distribution and positive predictive value of Mammography: Among these 94 cases,BI-RADS category 3microcalcification mainly displayed as dotted on Mammography lines(83%),mostly dispersion distribution and clustered distribution(both 41%);BI-RADS category 4a microcalcification largely displayed as amorphous blur(56%),mostly clustered distribution(64%);BI-RADS category 4b microcalcification mainly displayed as rough and uneven(46%),mostly clustered distribution(73%);BI-RADS category 4c microcalcification mostly displayed as subtle pleomorphic(67%),mostly segment distribution(58%);BI-RADS category 5 microcalcification mainly displayed as branched and worm-like(60%),mostly segment distribution(45%).PPV for dotted calcification is 11.1%,PPV for amorphous blur is 38.1%,PPV for rough and uneven is 18.1%,PPV for subtle pleomorphic is 96.1%,PPV for branched and worm-like is 100%;PPV for dispersion distribution of calcification is 11.1%;PPV for regional distribution is 60%;PPV for line-like,catheter-like distribution is 70%;PPV for segment distribution is 82%;PPV for clustered distribution is 54%.According the above analyzed shape and distribution data of microcalcification,calcification of highly malignant are subtle pleomorphic,branched and worm-like,both are higher than dotted,amorphous blur,rough and uneven,for distribution characteristics of calcification,PPV for segment distribution higher than all other distribution type.3 MRI imaging manifestations and positive predictive value(1)Palpable enhanced manifestations BI-RADS category 3-5 microcalcification on MRI:BI-RADS category 3 microcalcification more likely to be smooth edge palpable(100%),internal enhanced characteristics is ring enhancement(100%);BI-RADS category 4a microcalcification mostly are smooth edge(50%)or shallow lobular mass(50%),internal enhanced characteristics is homogeneous enhancement(100%).Most BI-RADS category 4b microcalcification are non-smooth edge(60%)round and oval palpable(80%),internal enhanced characteristics is heterogeneous enhancement(80%);BI-RADS category 4c microcalcification mostly displayed as burr edge(44.4%)round and oval palpable(52.5%),internal enhanced characteristics mostly are heterogeneous enhancement(60%).BI-RADS category 5microcalcification more likely to be non-smooth edge(44.4%)or burr edge(44.4%)round or oval palpable(52.5%),internal enhanced characteristics mostly are heterogeneous enhancement(100%).PPV for round or roundish palpable is 96.4%,PPV for Lobes-like is 86.7%,PPV for irregular type is100%,PPV for smooth edge palpable is 0.0%,PPV for non-smooth edged is100%,PPV for burr edged is 100%,for shallow lobular is 90.9%.Internal enhanced characteristics of lesion,PPV for homogeneous enhancement is66.7%,PPV for heterogeneous enhancement is 96.8%,PPV for ring enhancement is 0.0%,and PPV for interval enhancement is 83.3%.(2)Nonpalpable enhanced manifestations of BI-RADS category 3-5microcalcification: BI-RADS category 3 and 4a are mostly focal enhancement(63% and 42.9%);BI-RADS category 4b are mostly line-like and ductal-like(66.7%);BI-RADS category 4c are mostly line-like,ductal-like and segment enhancement(50%);BI-RADS category 5 are mostly segment enhancement(66.7%).Among nonpalpable enhanced,PPV for dotted enhancement is 60%,PPV for focal enhancement is 12.5%,line-like and ductal-like enhancement is85.7%,PPV for segment enhancement is 85.7%,PPV for regional enhancement is 25%,PPV for patchy enhancement is 0.0%.4 Analysis results(1)In palpable enhanced lesion,highly malignant enhanced as non-smooth edged irregular palpable,internal enhancement is heterogeneous enhancement;In nonpalpable enhanced lesion,highly malignant enhanced as line-like,ductal-like and segment enhancement.(2)In dynamic contrast enhanced MRI,MRI enhanced curve for benign lesions mostly are type I(80.6%),MRI enhanced curve for malignant lesions mostly are type III(50.9%),the different between benign and malignant lesions on MRI Dynamic contrast enhanced curve is statistical significance(P <0.05).(3)In this study,PPV for BI-RADS category 3 microcalcification that diagnosed by Mammography is 0.0%,PPV for BI-RADS category 4a microcalcification is 32%,PPV for BI-RADS category 4b microcalcification is 63.7%,PPV for BI-RADS category 4c microcalcification is 95.2%,PPV for BI-RADS category 5 microcalcification is 100%.(4)The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of BI-RADS category3-5 microcalcification diagnosed by Mammography are: 92.3%,38%,69.7%,67.6% and 78%.(5)The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of BI-RADS category 3-5microcalcification diagnosed by MRI are: 92.3%,73%,84.3%,82.8% and87%.5 Relationship between breast glands and calcification The sensitivity and specificity of Mammography and MRI test for calcification on different breast glands,the sensitivity and specificity for both fatty type glands(type a)and fibrous type glands(type b)of MRI test is 100%;Sensitivity for heterogeneous glands(type c)of X-Ray test is 91%,specificity is 31%,for MRI test,sensitivity is 91%,specificity is 69.7%.For heterogeneous dense glands BI-RADS 3-5 microcalcification,both test method has same sensitivity,but specificity of MRI test is much higher than Mammography test.For extremely dense(type d)glands,sensitivity of Mammography test is 100%,specificity is 33%,both sensitivity and specificity of MRI test is 100%.Therefor MRI test has advantage for heterogeneous dense glands and dense glands.Conclusion:1 MRI is difficult to display the microcalcification of breast,but it can show the morphological and hemodynamic changes of the microcalcification region.2 Specificity,accuracy,positive predictive value and negative predictive value of MRI test are higher than Mammography test.3 BI-RADS 3-5 breast microcalcification,especially intermediate calcification(benign and malignant identification difficulty)is diagnosis difficult for Mammography test,although MRI could not intuitively demonstrate calcification,still it has high advantage for benign and malignant identification of calcification,therefor,on a certain level,MRI could avoid overestimated or underestimated of calcification by Mammography test.4 MRI has no advantage for typical malignant calcification diagnosis.If MRI test are line-like,ductal-like and segmental enhancement for thiscalcification,biopsy should be applied to verify pathology result.5 Dynamic enhanced curve has a certain diagnostic efficacy for clustered calcification.6 Calcification on MRI,that shows diffuse enhancement,still has possibility to be malignant lesions.Follow-up review is required for calcification has no enhancement on MRI.Because of the high sensitivity,simple and easy of Mammography test for microcalcification,Mammography test is the primary method to examining breast cancer,although MRI has difficulty to identify microcalcification,but the features like high resolution and dynamic contrast enhanced are advantage to demonstrate histomorphology and hemodynamic changes for the corresponding region of microcalcification,has significance meaning of display and diagnosis for early breast lesions.