Is ultrasound valuable in breast cancer screening G. Villeirs Genitourinary Radiology Ghent University Hospital

Introduction Screening = the evaluation of a population of asymptomatic women in an effort to detect unsuspected disease at a time when cure is still possible

Introduction Screening = the evaluation of a population of asymptomatic women in an effort to detect unsuspected disease at a time when cure is still possible

Introduction high specificity high sensitivity avoid false positives! high sensitivity find as many subclinical cancers as possible! feasible and reproducible low cost

Introduction Screening = the evaluation of a population of asymptomatic women in an effort to detect unsuspected disease at a time when cure is still possible

Introduction Screening = the evaluation of a population of asymptomatic women in an effort to detect unsuspected disease at a time when cure is still possible

Introduction high specificity high sensitivity avoid false positives! high sensitivity find as many subclinical cancers as possible! feasible and reproducible low cost

Introduction high specificity high sensitivity avoid false positives! high sensitivity find as many subclinical cancers as possible! feasible and reproducible low cost

Introduction Screening = the evaluation of a population of asymptomatic women in an effort to detect unsuspected disease at a time when cure is still possible

Introduction Screening = the evaluation of a population of asymptomatic women in an effort to detect unsuspected disease at a time when cure is still possible

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction

Introduction high specificity high sensitivity avoid false positives! high sensitivity find as many subclinical cancers as possible! feasible and reproducible low cost

Introduction high specificity high sensitivity avoid false positives! high sensitivity find as many subclinical cancers as possible! feasible and reproducible low cost

Introduction high specificity high sensitivity avoid false positives! high sensitivity find as many subclinical cancers as possible! feasible and reproducible low cost

MAMMOGRAPHIC SCREENING

Mammographic Screening

Mammographic Screening Sensitivity 88% 83% 69% 62% 8,4% 48,1% 36,2% 7,3% 77% *Rosenberg RD. Radiology 1998;209:511-518 Yankaskas. Am J Roentgenol 2001;177:543 Carney. Ann Intern Med 2003;138:168

Mammographic Screening Specificity 97% 93% 91% 90% 8,4% 48,1% 36,2% 7,3% 93% *Carney, Ann Intern Med 2003;138:168

Mammographic Screening Sensitivity of 77% 4 out of 5 asymptomatic lesions are detected! Specificity of 93% acceptable number of false positives!

Mammographic Screening Sensitivity of 77% 4 out of 5 asymptomatic lesions are detected! Specificity of 93% acceptable number of false positives!

Mammographic Screening Sensitivity of 77% 1 out of 5 asymptomatic lesions are missed! Specificity of 93% acceptable number of false positives!

MAMMOGRAPHICALLY OCCULT ?

Mammographically Occult ? Was the mammogram of high enough quality? good positioning? technically good? Were previous mammograms available for comparison?

Mammographically Occult ? Was the mammogram of high enough quality? good positioning? technically good? Were previous mammograms available for comparison?

Mammographically Occult ? Was the mammogram of high enough quality? good positioning? technically good? Were previous mammograms available for comparison?

Mammographically Occult ? Was the mammogram of high enough quality? good positioning? technically good? Were previous mammograms available for comparison?

IMPORTANCE OF TRUE SONOGRAPHYCALLY DETECTED LESIONS

3.2 cm

Importance of true sonographycally detected lesions

Importance of true sonographycally detected lesions Small lesions are difficult to detect on US subtle signs small spiculations, lobulations, microcalcifications… lower resolution of sonography observer bias who has a lesion? where is the lesion?

Importance of true sonographycally detected lesions Small lesions are difficult to detect on US subtle signs small spiculations, lobulations, microcalcifications… lower resolution of sonography observer bias who has a lesion? where is the lesion?

Mammography Sonography

Importance of true sonographycally detected lesions Prevalence of (small) malignant lesions is much lower than prevalence of (small) benign lesions Excess of false positive findings!!

Importance of true sonographycally detected lesions Small lesions are difficult to detect on US subtle signs small spiculations, lobulations, microcalcifications… lower resolution of sonography observer bias who has a lesion? where is the lesion?

Importance of true sonographycally detected lesions Small lesions are difficult to detect on US subtle signs small spiculations, lobulations, microcalcifications… lower resolution of sonography observer bias who has a lesion? where is the lesion?

FEASIBILITY AND REPRODUCIBILITY

Feasibility and Reproducibility A screening examination should be easy to perform and reproducible extra 1.5 – 2 hours per mammographic unit per day (10 minutes per examination) quality assurance??? ultrasound equipment radiologist double reading

COST OF SCREENING

Cost of Screening Addition of sonography increases overall screening cost (if funded separately) due to: sonography reimbursement extra interventions (false positives)

Cost of Screening Other prevention strategies anti-tobacco campaigns investments in safer traffic prevention of infectious diseases suicide prevention …

SCIENTIFIC PROOF

Scientific Proof Ultrasound Screening Studies Buchberger, AJR 1999;173:921-927 Kaplan, Radiology 2001;221:641-649 Kolb, Radiology 2002;225:165-175 Crystal, AJR 2003;181:177-182 Corsetti, Radiol Med 2006;111:480-488

Scientific Proof Results 29857 women mammo + US screening 1327 (4,6%) referred for intervention (90% cytology or core-biopsy, 10% open biopsy) 103 mammographically occult tumors detected (µ = 1 cm) = 3,4/1000 women 1224 false positive!!! = B/M 12/1 Buchberger, AJR 1999;173:921-927 Kaplan, Radiology 2001;221:641-649 Kolb, Radiology 2002; 2002;225:165-175 Crystal, AJR 2003;181:177-182 Corsetti, Radiol Med (Torino) 2006;111:480-488

Scientific Proof Discussion Statistical law ↑ sensitivity = ↓ specificity ↓ sensitivity = ↑ specificity

Scientific Proof Discussion Increase of sensitivity by Biopsy of all microcalcifications Biopsy of all mammographic nodules Addition of sonography Screening with MRI!

Scientific Proof Discussion Seek for the highest sensitivity between the limits of an acceptable false positive rate EUROPEAN GUIDELINES

Screening No Screening Total Participation 35% 35.000 65.000 100.000 3/1000/year 105 195 300 Mammography : 77% 81 81 Mammo + US : 85% 89 89 +8 (+10%) Participation 45% 45.000 55.000 100.000 3/1000/year 135 165 300 Mammography : 77% 104 104 +23 (+28%)

Screening No Screening Total Participation 35% 35.000 65.000 100.000 3/1000/year 105 195 300 Mammography : 77% 81 81 Mammo + US : 85% 89 89 +8 (+10%) Participation 75% 75.000 25.000 100.000 3/1000/year 225 75 300 Mammography : 77% 173 173 +92 (+113%)

Participation versus US FIRST let’s increase the participation rate THEN let’s discuss the additional value of US

HIGH RISK POPULATION

High Risk Population High risk Higher cancer prevalence Familial breast cancer or genetic predisposition Mammographically dense breasts Higher cancer prevalence High sensitivity needed Specificity less critical

High Risk Population 1517 women mammo + echo (2/3/4) 1199 “normal risk” 28 (2,34%) referred for intervention 3 tumors detected (detection rate 0,25%) B/M-ratio 8,33/1 318 “high risk” 10 (3,14%) referred for intervention 4 tumors detected (detection rate 1,27%!!) B/M-ratio 1,50/1!! Crystal, AJR 2003;181:177-182

CONCLUSIONS

Conclusions Mammography is the best screening tool Sonography is an optimal diagnostic tool Use of sonography as an adjunct to mammographic screening is problematic and should currently not be adopted Probably useful in screening of high risk women with dense breasts