Medical imaging techniques for breast cancer - A Study (Early Detection using Digital Portable Mammography)

1. 1

2. Friends ,
 In conformity with IEEE Vision “To foster technological innovation and excellence for the benefit of humanity”.
 I am going to deal with one of the most hazards and common ailments that the women are facing today.
 The problem is particularly acute and alarming among the rural and less literate women hood.
 Breast Cancer has now become a common ailment, the policy makers, Social Activists and people at medical profession are scratching there head to contain this dreadful disease. The age old adage says that precaution is better than prevention.
2

3. Breast cancer is one of the significant causes
of the mortality among women. Compared to other types of cancer, breast
cancer (in women) has a higher mortality rate. Scientific investigations done in the past few
decades do not specifically attribute causes
for the occurrence of breast cancer in women.
Breast Cancer
3

4. Continue .... However, there are many risk factors that are indicated as possibilities for the occurrence of breast cancer viz., age, previous medical history, early menstruation, late menopause, genetic predisposition, family history and changing life styles.
Breast cancer is a malignant (cancerous) growth that begins in the fibro glandular tissue of the breast.
Breast cancer is inclined towards gender specificity; more towards women and less towards men.
4

5. BREAST CANCER IN THE WORLD
1.15 million new cases
Incidence increasing in most countries
470 000 deaths
Half of the global burden in low- and medium-resourced countries
5

6. 0
20
40
60
80
100
FIVE TEN TWENTY
RELATIVE SURVIVAL RATES
YEARS
MINIMAL CARCINOMA NEGATIVE NODES POSITIVE NODES DISTANT METS
Breast Cancer Survival
6

7. Female Breast Anatomy Glandular Tissue
7

8. The Human Breast is a well differentiated apocrine sweat gland which secretes milk during lactation. The two breast lie anterior to the right and left pectoral muscles, extending from sternum laterally to the mid auxiliary line.
Virtually all breast cancers arise from the Glandular tissue.
The Breast Anatomy
8

9. Several studies suggests that women in whom ducts occupy 25% or more of breast volume or in whom fibroglandular density occupies more that 50% of breast volume may be at higher risk of breast cancer than average.
Characteristic of breast cancer are masses, particularly ones with irregular or “spiculated” margin; clusters of micro calcifications; and architectural distortion of breast structures.
The Breast Anatomy
9

10. Breast Gland
10
Each breast has 15 to 20 sections (lobes) arranged like the petals of daisy
Inside each lobe are many smaller structures called lobules
At the end of each lobule are tiny sacs (bulbs) that can produce milk

11. Ducts
11
Areola Lobes, lobules, and bulbs are Linked by a network of thin tubes (ducts) Ducts carry milk from bulbs toward dark area of skin in the center of the breast (areola) Ducts join together into larger ducts ending at the nipple, where milk is delivered

12. Blood Vessels
12
Oxygen, nutrients, and other life-sustaining nourishment are delivered to breast tissue by the blood in the arteries and capillaries.

13. Three Types of Vessels
13
Bacteria Blood Vessels
Cell life 2
Lymph
Nodes Lymph Vessels
3 Milk Lobules
Ducts Nipple
1

14. Signs and Symptoms
14 Most common: lump or thickening in breast. Often painless Change in color or appearance of areola Redness or pitting of skin over the breast, like the skin of an orange Discharge or bleeding Change in size or contours of breast

15. Signs of Breast Cancer Masses Calcifications Bilateral Asymmetry Architectural Distortion (subtle, often missed)
15

16. Masses Breast cancer causes a
desmoplastic reaction in
breast tissue
A mass is observed as a bright, hyper-dense object Mammogram with a mass
16

17. Calcification Deposits of calcium in breast tissue Mammogram with Calcification 17

18. Bilateral Asymmetry Differences in the overall appearance of one breast with reference to the other 18

19. Architectural Distortion
Third most common mammographic sign of nonpalpable breast cancer
The normal architecture of the breast is distorted
No definite mass visible
Spiculations radiating from a point
Focal retraction or distortion at the edge of the parenchyma Mammogram with Architectural Distortion 19

20. Accuracy of Mammography
Stage of Disease
% detection
Mammography
Physical Examination
Minimal Carcinoma
Negative Nodes
Positive Nodes
97
92
93
33
51
77
20

21. Breast Self Examination Clinical Breast Exam Mammography
Methods of detection of breast cancer
21

22. Breast Self Examination 22

23. Clinical Breast Exam 23

24. Mammography 24

25. Mammography – An Introduction
Mammography is a radiographic examination that is specially designed for detecting early breast cancer, yielding a significant improvement in breast cancer survival.
Mammography has been used in clinical practice since 1927 in the diagnosis of breast abnormalities.
In the late 1950s, the pioneering work of Gershon – Cohen and Egan demonstrated that even clinically occult cancers of early detection of breast cancer by screening asymptotic women.
25

26. Continue…..
Since the first mammography units (xeromammography and screen-film mammography in the 1970s) became available, both the equipment and the examination procedure have changed and progressed.
A high degree of accuracy was developed with this technique to differentiate between Benign and Malignant disease. 26

27. At 40 and older mammography is used to screen for breast cancer in women without symptoms.
Mammography is the most sensitive examination for detection of early breast cancers.
At 40 and older Breast Self Examination and Clinical Breast Examination are used to detect breast cancers not seen on a mammogram because of technical limitations, interval tumor growth or breast cancers missed on the mammogram.
Continue….. 27

28. Past Present ANALOGICAL TECHNOLOGY DIGITAL TECHNOLOGY
Screening
Clinical mammography
Computed radiography (CR)
Digital direct
Computed Aided Diagnosis (CAD)
Tomosynthesis - 3D
CESM
Mammography 28

29. Analog Mammography
In analog mammography a screen film is used to capture the image. A low energy X-ray is focused on the breast and the breast is compressed. Automatic exposure control is provided to avoid unnecessary exposure to the patient.
A screen film in the form of cassette is placed beneath the breast position. On the exposure of x-ray radiation the image is collected in the screen film.
In screening mammography, two x-ray images of each breast, in the mediolateral oblique and craniocaudal views, are routinely acquired. 29

30. Constraints and Limitations of analog mammography …
Films provide benchmark quality images. However, lost, destroyed, poorly processed or misplaced films cause retakes and increases in patient radiation dose.
Images on film cannot be further enhanced because film does not have separate processes for image capture and display.
Unable to recognise the presence of micro calcifications which represent the most sensitive mammographic sign of early breast cancer .
30

31. The film serves as an image acquisition detector , a storage mechanism and a display device , performing these several functions results in limitations such as poor contrast and defects in recapturing the image .
Over exposure of X- ray results in dark images and under exposure of X- ray results in light images.
Constraints and Limitations of analog mammography … 31

32. 32

33. Digital Mammography
In a digital mammographic system the film/screen cassette is replaced by a chemical screen along with a digital detector which detect the x-ray photons leaving the breast. The chemical screen converts the x-ray photons into light which transferred through a fiber optical reducer to the CCD (Charged Couple Device) detector. The CCD converts the incident light into a digitized analogue signal and this signal is displayed on a computer monitor. The exposure is terminated when a sufficient signal to noise ratio is achieved. “The most fertile territory for major advances in the detection and diagnosis of minimal breast cancers” 33

34. Advantages of Digital Mammography
Improved detection efficiency
A linear dynamic range
Increased signal-to-noise ratio (SNR)
Excellent Image Handling
Data in Digital form
Computer Aided Detection
Compatibility with PACS and Telemammography
34

35. In digital mammography screen-film system has been replaced by Detectors to give the digital images 35

36. Side by side 36

37. 37

38. Directed Digital Radiography (DDR)
Directed digital radiography, a
term used to describe total
electronic imaging capturing.
Eliminates the need for an image plate altogether.
38

39. 39

40. CR vs DR
CR
Imaging plate
Processed in a Digital Reader
Signal sent to computer
Viewed on a monitor
DR
Transistor receiver (like bucky)
 Directly into digital signal
seen immediately on monitor
40

41. Computer-Aided Diagnosis
Mammography allows for efficient diagnosis of breast cancers at an earlier stage
Radiologists misdiagnose 10-30% of the malignant cases
Of the cases sent for surgical biopsy, only 10-20% are actually malignant
41 CAD systems can assist radiologists to Reduce these problems

42. Database Approach to Computer-Aided Diagnosis 42 Content-based image retrieval techniques can provide radiologists “visual aids” to increase confidence in their diagnosis The database consists of a large number of images with verified pathology results Diagnosis is done by submitting the suspected mass region as a query to retrieve similar cases from the database

43. A Mammography CAD System [Giger et al.]
43 Probability of malignancy Similar images of known diagnosis Indicates the unknown lesion relative to all lesions in the database

44. What do the potential technical advantages of digital mammography mean for radiologists, patients and institutions 44

45. Technical Advantage
For radiologists, the advantages mean consistently better. Clinically, image quality is judged in terms of the adequacy of the portrayed normal anatomy and the ability to characterise detected lesions. Consistent improvement, even if minimal, in one or both of these areas means a decrease in the number of errors due to poor imaging technique and poor human judgment, as well as an increase in the efficiency and accuracy of mammography.
45

46. Major improvement, however, is expected in cases where analog mammography is currently less successful. These cases include women with radiodense breasts who can comprise upto 40% of the general population, cases where lesions are located in thinner, less absorbing regions of the breast, and cases with inhomogeneous parenchymal density distributions.
Technical Advantage 46

47. Technical developments
Full Field Digital Mammography applications
CAD
Tomosynthesis
CESM 47

48. Full-field digital mammography (FFDM)
Recently approved by the U.S. Food and Drug Administration (FDA), this technique involves taking digital images of the breast. Digital images are captured electronically and can be viewed on a computer. Their magnification, brightness and contrast can be adjusted and enhanced to better reveal abnormalities. 48

49. DBT may improve cancer detection by mammography by enabling readers to detect lesions which are very difficult or impossible to visualize on conventional imaging due to overlying glandular tissue
Digital Breast Tomosynthesis
49

50. Digital Breast Tomosynthesis (DBT) L. Pescarini et al. Attualità in senologia; 2008
Digital Breast Tomosynthesis
50

51. Contrast Enhanced Digital Mammography
Dual Energy subtraction Digital Mammography (DEDM) Double exposure with iodine contrast and acquisition of two different images to "high" and "low" energy
Properly choosing the two energies, you can basically "erase" the background and emphasize the contrast of the pathological structures
Temporal Subtraction
51

52. Dual Energy subtraction Digital Mammography
Courtesy of G.E.
52

53. X-ray mammography Ultrasound Magnetic Resonance Imaging (MRI) Positron Emission Mammography (PEM)
Screening Methods 53

54. Breast Ultrasound
Diagnostic test for evaluation of mammographic and palpable abnormalities
 Can differentiate cystic from solid
 Characterize solid masses
 Evaluate the axilla for metastatic disease
 First exam for patients less than age 30
Breast ultrasound is a noninvasive (the skin is not pierced) procedure used to assess the breasts. Ultrasound technology allows quick visualization of the breast tissue. Ultrasound may also be used to assess blood flow to areas inside the breasts. The examination is often used along with mammography.
54

55. Breast Ultrasound
Screening ultrasound
 No radiation, no compression
 28% increase cancer detection over mammography alone
Not ready for widespread use
Low specificity, higher cost, lack of availability
Low sensitivity for calcifications of DCIS
A breast ultrasound uses sound waves to make a picture of the tissues inside the breast.
A breast ultrasound can show all areas of the breast, including the area closest to the chest wall, which is hard to study with a mammogram.
Breast ultrasound does not use X-rays or other potentially harmful types of radiation.
55

56. Breast MRI
 Excellent tissue differentiation
 High sensitivity for breast cancer
 Not limited by breast density
 No ionizing radiation
56
Magnetic resonance imaging (MRI) is a diagnostic procedure that uses a combination of a large magnet, radio waves, and a computer to produce detailed images of organs and structures within the body.

57. Breast MRI Applications
Implant evaluation
Inconclusive mammography/ultrasound
Cancer staging
Response to chemotherapy
Search for occult primary neoplasm
Cancer screening
57

58. MRI Breast Cancer Screening
Why not everyone?
Expense
Invasive procedure
Contraindicated in some patients
Lack of expertise and MRI availability
Low specificity results in excess biopsies and additional follow-up
58
However, in the circumstance of both a negative mammogram and a negative physical examination, the probability of a breast cancer being diagnosed by MRI is extremely low.
MRI sensitivity for invasive cancer approches 100%, but is only 60% at best for DCIS .

59. Positron Emission Mammography (PEM) PEM is an alternative for women who cannot tolerate MR imaging PEM has improved specificity compared with MR imaging and is therefore likely to prompt unnecessary biopsies Review of mammograms together with MR or PEM images, or both, improves the detection of additional disease
Implications for patient care
59

60. Positron Emission Mammography
Injection of fluorodeoxyglucose (FDG)
Cancers take up FDG
High specificity but lower sensitivity than MRI
High radiation dose and expense preclude use in routine screening
Assess extent of disease, response to treatment, evaluation for recurrence
60

61. 61

62. Breast Computed Tomography
Lindfors KK, et al, Dedicated breast CT: initial clinical experience. Radiology 2008;246(3):725–733.
Good resolution
Improved patient comfort over mammography
Higher radiation dose, expense and lack of availability makes widespread use unlikely
62

63. Nuclear medicine is a branch of radiology that involves administering small amounts of radioactive material (called radiopharmaceuticals or radiotracers) to a patient by injection, inhalation, or pill.
Nuclear Medicine or scintimammography
 The radiopharmaceutical eventually accumulates in a particular organ or area of the body, where it gives off energy in the form of gamma rays.
 Nuclear medicine breast imaging (you may also hear the term molecular breast imaging) uses short-term radioactive agents that are given through an IV.
63

64.  Nuclear medicine breast imaging is a supplemental breast exam that may be used in some patients to investigate a breast abnormality.
 A nuclear medicine test is not a primary investigative tool for breast cancer but can be helpful in selected cases after diagnostic mammography has been performed.
Limitations . . .
 Nuclear medicine breast imaging involves injecting a radioactive tracer (dye) into the patient. Since the dye accumulates differently in cancerous and non-cancerous tissues, scintimammography can help physicians determine whether cancer is present.
64

65. Early Detection Is Your BEST PROTECTION
If breast cancer is found and treated early, the five-year survival rate is 98 percent.
The social prejudices and stigma associated in screening of breast is to be sensitized.
The success of the scheme depends upon the involvement of radiologists and lab attendants who have to handle with delicate and humane.
Another success of the scheme rests upon instead of bringing the people to lab, the lab itself has to go in search of the patient. For which a handy and portable mammogram has to developed for instant and hassle free Service. 65

66. Portable Mammography
GE unveiled an impressive portable mammography concept as part of a portfolio of integrated technologies aimed at combating cancer.
The SenoCase is mobile mammography system which can be folded and easily stored in a car boot.
66

67. According to GE, such portability could remove geographical barriers to regular breast screening for many women on a global scale.
The system could also be more cost effective than conventional mammography systems, making it more accessible to smaller practices and clinics.
A standard field of view Cesium Iodide detector
Similar image quality to a full-field digital mammography system
A user-friendly interface, operable by a single clinician
67

68.  Digital Portable Mammography model was preferred in employee surveys.
 Employee feedback confirmed that Women Diagnostic Center mammograms are more convenient, private and familiar because employees feel more comfortable. 68

69. Digital mammography has proven to be an essential tool in the diagnosis, treatment and fight against breast cancer. And studies have shown that routine mammograms can help reduce breast cancer mortality.
The important thing is that you make annual mammography screening a top priority for yourself and the women you care about. 69

70. 70