DUAL ENERGY CONTRAST ENHANCED SPECTRAL MAMMOGRAM : AS A PROBLEM SOLVING TOOL IN EQUIVOCAL CASES

Abstract ID IRIA-1121

Breast cancer incidence has increased by more than 20% ,mortality has increased by 14%(1)

One in four of all cancers in women(1)

Full field digital mammography is well established , cost effective screening modality in detection of breast cancer.

Certain limitations -mammography • In dense breasts

• In lesions identified only on one view (for mammogram)

• In detection of subtle lesions

Case 1A 48 yr old female with dense breast,

Sensitivity of conventional mammogram

98% for fatty breasts 48% for dense breasts(3)

In order to increase sensitivity a newer imaging technique called Contrast enhanced digital mammogram (CEDM) which could demonstrate neovascularization was incorporated into breast imaging .

Digital mammogram CEDM

Case 237 yr old ,with dense breast, for routine screening:

Case 237 yr old ,with dense breast, for routine screening:

After intravenous iodinated contrast injection

A simultaneous pair of high energy and low energy exposures were made for both the craniocaudal and mediolateral oblique view of both breasts

A recombined image was obtained using specific dual energy recombination algorithm.

How Dual Energy Contrast Enhanced Mammography Is Performed ?

Figure 1 , schematic representation of sequence of images acquired

GOAL OF OUR STUDY

To assess the role of additional CEDM in occult /equivocal findings on digital mammogram

Assessing accuracy of CEDM in predicting probability of malignancy

WHERE IS CEDM MOST USEFUL? Identifies occult lesions in dense

breastDemonstrates extent of lesion, ductal

extension Establishes multifocalityIdentifies site for histopathologyServes as complete assessment ,

eliminating questionable findings to be followed up

Follow up to assess response to treatment

Case3Suspicious microcalcification:

Suspicious microcalcification:

Case 4Subtle architectural distortion

Case 4Subtle architectural distortion

• Is there any role for CEDM in mammography detected malignancy ?

case 5Ductal extension demonstrated on CEMG

case 5Ductal extension demonstrated on CEMG

Case 6Multifocality shown on CEMG

Case 6Multifocality shown on CEMG

Case 7True extent

Case 7True extent

• Role in cases with multiple lesions ?

Case 8Identifies BIRADS IV lesion among multiple lesions:

Case 9 & 10Proves benign nature

In following up response to treatment ?

Case 11Follow up post chemoradiation- shows response

OUR STUDY

• 44 consented patients underwent mammogram(MG) and contrast enhanced mammogram(CEMG)

• Confidence of presence of lesion on a three point scale

• Probablity of malignancy as BIRADS was assessed independently by two well qualified radiologists.

• Histopathology taken as gold standard.

• Interobserver variation calculated by obtaining kappa value.

Histopathology of study group

Malignant /precancerousBenign/ inconclusive

1 - Specificity1.00.80.60.40.20.0

Sens

itivi

ty

1.0

0.8

0.6

0.4

0.2

0.0

Reference Linece +mg observer 2Mg .o2

Source of the Curve

ROC Curve

Diagonal segments are produced by ties.

1 - Specificity1.00.80.60.40.20.0

Sens

itivi

ty

1.0

0.8

0.6

0.4

0.2

0.0

Reference Line

Mg+cemg 123 observer 1

Mg .o1

Source of the Curve

ROC Curve

Diagonal segments are produced by ties.

Area under curve for confidence of presence – observer 1Mg -0.485Mg+cemg -0.685

Area under curve for confidence of presence- observer 2Mg -0.526Mg+cemg -0.635

1 - Specificity1.00.80.60.40.20.0

Sens

itivi

ty

1.0

0.8

0.6

0.4

0.2

0.0

Reference Line

mg+cemg BIRADS observer 1

Mg birads impression.o1

Source of the Curve

ROC Curve

Diagonal segments are produced by ties.

1 - Specificity1.00.80.60.40.20.0

Sens

itivi

ty

1.0

0.8

0.6

0.4

0.2

0.0

Reference Line

Mg + cemg biradsobserver 2

Mg birads.o2

Source of the Curve

ROC Curve

Diagonal segments are produced by ties.

Area under curve for probablity of malignancy – observer1 Mg 0.718Mg+cemg=0.812

Area under curve for probablity of malignancy –observer 2Mg 0.738Mg+cemg 0.812

CONSISTENCY

P = 0.000MEASURMENT OF AGREEMENT KAPPA =0.837

Cross tabulation of contrast enhanced mammogram findings between observer 1 and 2

CEMG(2)CEMG(1)

Not seen Faintly seen seen total

Not seen 4 9.1% 0 0% 1

2.3% 5 11.4%

Faintly seen

0 0% 2 4.5% 0 0% 2 4.5%

seen 0 0% 1 2.3% 36 81.8% 37 84.1%

total 4 9.1% 3 6.8% 37 84.1% 44 100%

MG (1) MG+CEMG(1) MG(2) MG+CEMG(2)

Confidence of presence

Sensitivity 76.5 97 85 97

Specificity 20 40 20 30

PPV 76.5 85 78 83

NPV 20 80 29 75

P value 0.815 0.001 0.687 0.009

BIRADS Sensitivity 74 82 68 82

Specificity 70 80 80 80

PPV 89 93 92 93

NPV 44 57 42 37

P value 0.012 0.000 0.007 0.000

Mammogram versus mammogram + contrast enhanced mammogram for two observers, taking histopathology as gold standard

ENCOURAGING CLINICAL RESULTS HAVE BEEN PUBLISHED DURING THE LAST FEW YEARS

• Contrast-enhanced digital mammography : initial clinical experienceJong RA et al. Radiology 2003; 228:842-850

• Dual-energy contrast enhanced digital subtraction mammography : feasibilityLewin JM et al. Radiology 2003; 209;261-268

• Digital mammography using iodine-based contrast media : initial clinical experience with dynamic contrast medium enhancement. Diekmann F et al, Invest radiol 2005

• Evaluation of tumor angiogenesis of breast carcinoma using Contrast Enhanced Digital Mammography. Dromain C et al, AJR 2006; 187:W528-37.

• Contrast-enhanced digital mammography ; Clarisse Dromaina,∗, Corinne Balleyguiera, Ghazal Adlera, Jean Remi Garbayb, Suzette Delalogec European Journal of Radiology 69 (2009) 34–42

• Dual-energy contrast-enhanced digital mammography: initial clinical results of a multireader, multicase study. Clarisse Dromain, 1 Fabienne Thibault,2 Felix Diekmann,3 Eva M Fallenberg,3 Roberta A Jong,4 Marcia Koomen,5 R Edward Hendrick,6 Anne Tardivon,2 and Alicia Toledano Breast Cancer Res. 2012; 14(3): R94. Published online Jun 14, 2012. doi:  10.1186/bcr3210 PMCID: PMC3446357

TAKE HOME POINTS

Contrast enhanced mammogram has definite role

In identifying occult lesions in dense breast

Demonstrates ductal extension

Establishes multifocality

Identifies site for histopathology in case of multiple lesions

Assess response to treatment

Serves as complete assessment tool,eliminating questionable findings to be followed up

REFERENCES

• 1  Golobocon 2012 released on 12 th dec 2013: http://www.iarc.fr/en/media-centre/pr/2013/pdfs/pr223_E.pdf

• 3Boyd NF, Byng JW, Jong RA, Fishell EK, Little LE, Miller AB, et al. Quantitative classification of mammographic densities and breast cancer risk: Results from the Canadian National Breast Screening Study.J Natl Cancer Inst. 1995;

• 7.Contrast-enhanced digital mammography Clarisse Dromaina,∗, Corinne Balleyguiera, Ghazal Adlera, Jean Remi Garbayb, Suzette Delalogec European Journal of Radiology 69 (2009) 34–42  

• 8.Prionas ND, Lindfors KK, Ray S, Huang SY, Beckett LA, Monsky WL,Boone JM: Contrast-enhanced dedicated breast CT: initial clinical experience. Radiology 2010, 256:714-723.

• 9 Hendrick RE: Radiation doses and cancer risks from breast imaging studies. Radiology 2010, 257:246-253.

• 10. American College of Radiology: Breast Imaging Reporting and Data System: BI-RADS. 4 edition. Reston, VA: American College of Radiology; 2003.

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