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

2. 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

3. 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

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

5. 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

6. 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

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

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

9. 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

10. 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

11. Introduction

12. Introduction

13. Introduction

14. Introduction

15. Introduction

16. Introduction

17. Introduction

18. Introduction

19. Introduction

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

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

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

23. MAMMOGRAPHIC SCREENING

24. Mammographic Screening

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

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

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

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

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

32. MAMMOGRAPHICALLY OCCULT ?

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

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

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

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

41. IMPORTANCE OF TRUE SONOGRAPHYCALLY DETECTED LESIONS

42. 3.2 cm

43. Importance of true sonographycally detected lesions

44. 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?

45. 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?

46. Mammography Sonography

47. 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!!

48. 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?

49. 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?

50. FEASIBILITY AND
REPRODUCIBILITY

51. 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

52. COST OF SCREENING

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

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

55. SCIENTIFIC PROOF

56. Scientific Proof Ultrasound Screening Studies
Buchberger, AJR 1999;173:
Kaplan, Radiology 2001;221:
Kolb, Radiology 2002;225:
Crystal, AJR 2003;181:
Corsetti, Radiol Med 2006;111:

57. 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:
Kaplan, Radiology 2001;221:
Kolb, Radiology 2002; 2002;225:
Crystal, AJR 2003;181:
Corsetti, Radiol Med (Torino) 2006;111:

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

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

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

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

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

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

65. HIGH RISK POPULATION

66. 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

67. 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:

68. CONCLUSIONS

69. 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