Background on: Breast Cancer, X-Ray and MRI Mammography

1. Background on: Breast Cancer, X-Ray and MRI Mammography Ernesto Coto Vienna University of Technology Institute of Computer Graphics and Algorithms Computer Graphics Group Ernesto Coto - Institute of Computer Graphics and Algorithms

2. Introduction • First stage of a research about the State of the Art on Mammography for Breast Cancer Detection • Focuses on the background knowledge about Breast Cancer, X-Ray and MRI Mammography Ernesto Coto - Institute of Computer Graphics and Algorithms

3. Background: Breast Cancer • Cancer is a general term that is used to describe a group of more than 100 diseases that cause cells in the body to divide and reproduce abnormally without control • These cells may join together to form a mass of extra tissue known as a tumor. Tumors can be malignant or benign • Malignant tumors can break away from tumors and travel, or metastasize • Breast cancer refers to a malignant tumor that has developed from breast cells Ernesto Coto - Institute of Computer Graphics and Algorithms

4. Background: Breast Cancer • The female breast has two main components: glandular tissue and connective tissue • There are two general categories of breast cancer • Non-invasive (or in situ) cancer confined to lobules or ducts • Invasive cancer spread to fatty connective tissue Ernesto Coto - Institute of Computer Graphics and Algorithms

5. Background: Breast Cancer • When breast cancer is detected before it has spread to lymph nodes or to other parts of the body, the 5-year survival rate is 97% • Early detection and early treatment can improve the chances of surviving breast cancer. Currently, mammography is the best tool available to detect the earliest warning signs of breast cancer Ernesto Coto - Institute of Computer Graphics and Algorithms

6. Background: X-Ray Mammography • A mammogram is an x-ray examination of the breasts, used to detect and diagnose breast diseases • Screening mammography is used as a preventive measure for women who have no symptoms of breast disease • Diagnostic mammography involves additional x-rays of the breast to provide different views of the suspicious area, if an abnormality is detected during screening mammography, or in women with breast complaints • The x-rays can be taken at different angles tailored to the specific area of abnormality. In addition, magnification views or spot compression can be used to make the area easier to evaluate Ernesto Coto - Institute of Computer Graphics and Algorithms

7. Background: X-Ray Mammography • Mammography procedure • Special x-ray machines developed exclusively for breast imaging are used to produce mammography films. These machines use very low doses of radiation and produce high-quality x-rays Ernesto Coto - Institute of Computer Graphics and Algorithms

8. Background: X-Ray Mammography • Mammography procedure • The patient wears an open wrap and undress above the waist Ernesto Coto - Institute of Computer Graphics and Algorithms

9. Background: X-Ray Mammography • Mammography procedure • Compressing the breast is necessary to obtain the best image Ernesto Coto - Institute of Computer Graphics and Algorithms

10. Background: X-Ray Mammography • Mammography procedure • When the breast is positioned and compression is complete, the technologist will leave the room or step behind a screen and turn on the x-ray source Ernesto Coto - Institute of Computer Graphics and Algorithms

11. Background: X-Ray Mammography • Mammography procedure • Magnification views or spot compression could be performed too Ernesto Coto - Institute of Computer Graphics and Algorithms

12. Background: X-Ray Mammography • Results • Calcifications are tiny calcium deposits within the breast tissue. Calcifications are classified as microcalcifications (< 1/50 inchs) or macrocalcifications (larger) • Masses • Can be solid or liquid (Cyst) Ernesto Coto - Institute of Computer Graphics and Algorithms

13. Background: X-Ray Mammography • Staging • Staging is the process used to determine the extent a cancer has spread beyond the primary site • The system used to describe staging is the Staging System of the American Joint Committee on Cancer (or TNM system), it evaluates three components to determine the stage of a cancer: • T = The extent of the tumor, expressed in a numerical value from 0 to 4. Higher T numbers indicates a larger tumor or more extensive spread • N = the extent to which the cancer has spread to lymph nodes near the breast and the degree to which the affected nodes are fixed to other structures under the arm. It is expressed in a numerical value from 0 to 3, with the higher number denoting more extensive spread • M = the extent to which the cancer has metastasized to distant organs or to lymph nodes that are not next to the breast. It is shown in a numerical value from 0 to 1, with 1 indicating the most extensive spread Ernesto Coto - Institute of Computer Graphics and Algorithms

14. Background: X-Ray Mammography • Mammography cannot determine whether an abnormal area is cancer, but it can provide guidance for further screening or diagnostic tests. • Results of mammograms are reported using a standardized system called the Breast Imaging Reporting and Data System (BIRADS) • Results range from “Assessment incomplete” to “Highly Suggestive of Malignancy” Ernesto Coto - Institute of Computer Graphics and Algorithms

15. Background: X-Ray Mammography • Despite Mammography is acknowledged to be the most effective method of screening for breast cancer, the interpretation of screening mammograms is challenging • The combination of viewing a large number of cases, radiologist fatigue and the complex image structure of the breast on a mammogram can result in false negative mammogram readings • Several retrospective studies have shown that 20% to 40% of breast cancer goes undetected at the screening stage • In addition, finding cancer does not always mean saving lives Ernesto Coto - Institute of Computer Graphics and Algorithms

16. Background: X-Ray Mammography • Less common diagnostic procedures • Magnetic Resonance Imaging (MRI) • Digital Mammography • Positron Emission Tomography • Ultrasound Ernesto Coto - Institute of Computer Graphics and Algorithms

17. Background: MRI Mammography • Magnetic Resonance Imaging (MRI) can be used to obtain three dimensional images of the inner parts of the human body, without using X-rays • MRI breast imaging is a supplemental tool, in addition to mammography, to help diagnose breast cancer • MRI advantages over X-ray or CAT • No radiation • The ability to generate arbitrary three-dimensional views of an object of interest • The possibility to generate images of “soft“ body structures Ernesto Coto - Institute of Computer Graphics and Algorithms

18. Background: MRI Mammography • MRI Mammography Procedure • The main component of most MRI systems is a large tube-shaped or cylindrical magnet • The patient has to wears a wrap and give away any metal object Ernesto Coto - Institute of Computer Graphics and Algorithms

19. Background: MRI Mammography • MRI Mammography Procedure • To begin the MRI exam, the patient is positioned on a special table inside the MRI system opening. A breast coil is used. Ernesto Coto - Institute of Computer Graphics and Algorithms

20. Background: MRI Mammography • Contrast Enhanced MRI • The method is based on the fact that a carcinoma is usually well vascularized due to its strong growth. Thus a contrast medium will quickly accumulate in the tumor • The evaluation essentially consists of finding suspicious regions in the images, calculating the absorption of contrast-medium in those regions, and deriving the diagnosis from that data Without contrast With contrast Ernesto Coto - Institute of Computer Graphics and Algorithms

21. Background: MRI Mammography • Benefits of Breast MRI • Can image breast implants and ruptures • Highly sensitive to small abnormalities • Used effectively in dense breasts • Can evaluate inverted nipples for evidence of cancer • Can evaluate the extent of breast cancer • Can help determine what type of surgery is indicated (lumpectomy or mastectomy) • May detect breast cancer recurrences and residual tumors after lumpectomy • Can locate primary tumor in women whose cancer has spread to axillary (armpit) lymph nodes • Can spot or characterize small abnormalities missed by mammography • May be useful in screening women at high risk for breast cancer, according to recent studies Ernesto Coto - Institute of Computer Graphics and Algorithms

22. Background: MRI Mammography • Limitations of Breast MRI • MRI takes 30-60 minutes compared to 10-20 minutes for screening mammography • The cost of MRI is several times the cost of mammography • MRI requires the use of a contrast agent • MRI patients must tolerate any claustrophobia • MRI can be non-specific; often cannot distinguish between cancerous and non-cancerous tumors • Minimally invasive breast biopsy techniques need to be further developed to evaluate abnormalities detected with MRI • Advanced MRI techniques are often not available at most centers (currently available at research centers) Ernesto Coto - Institute of Computer Graphics and Algorithms

23. Further work • CAD Systems and Techniques for Mammography • Registration • Segmentation • Visualization Ernesto Coto - Institute of Computer Graphics and Algorithms