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Appendix A

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					Appendix A
Other benign breast conditions not presented in this thesis: 1. Breast Calcifications. Calcifications are small deposits of calcium salts. They develop naturally as the breast ages and changes, and can occur with other benign breast conditions such as fibro adenomas and cysts. They can also occur as a reaction to inflammation and foreign bodies such as implants or stitches. Calcifications are very common and in most cases are harmless. Occasionally, however, they can be a sign of breast cancer. Calcifications are very small and are not palpable. This means they are usually first discovered on an x-ray mammogram where they show up as white spots, due to the high atomic number of calcium compared with normal breast tissue (see chapter 1.4). 2. Duct Ectasia and Periductal Mastitis During the menopause it is normal for the ducts behind the nipple to become dilated. This is known as duct ectasia. A result of this is that fluid can collect in the ducts and so block them. In addition the lining of the ducts can become ulcerated, causing pain. This can lead to inflammation or infection in the ducts and bloody or clear discharge from the nipple. Duct ectasia can often be identified by a palpable lump behind the nipple or by the appearance of scar tissue behind the nipple, which can eventually cause the nipple to invert. Periductal mastitis affects younger women. It occurs when the ducts around the nipple become inflamed or infected and has similar symptoms to duct ectasia. 3 Fat Necrosis Fat necrosis is a condition in which the neutral fats in the cells of adipose tissue break down into fatty acids and glycerol. It causes the formation of a firm, round lump and mainly occurs in an area of fatty breast tissue that has been damaged. The lump is usually painless, and the skin around it may look red, bruised or dimpled. 4 Hyperplasia. Hyperplasia is caused by increased growth in the size and number of normal cells within a part of the breast. It can occur in the ducts (ductal hyperplasia) or the lobes (lobular hyperplasia).

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Sometimes the cells develop an irregular pattern and these are known as atypical ductal hyperplasia and atypical lobular hyperplasia. If these cell changes in the lobes are very irregular, the condition is known as lobular carcinoma in situ (LCIS). This is not a true cancer (carcinoma) but an intermediate stage where the abnormal cells fill up the lobes. As the abnormal cells in the ducts or lobes have the potential to spread to the surrounding tissue, atypical hyperplasia and LCIS have been shown to slightly increase the risk of developing breast cancer in the future. This risk is further increased when there is a history of breast cancer in the family. 5 Intraductal papilloma An intraductal papilloma is a benign wart-like lump within a duct just behind the areola. Symptoms can include a small lump under the areola or discharge of clear, sticky or bloodstained fluid from the nipple. Intraductal papillomas can occur in both breasts at the same time and are sometimes found by chance following breast surgery. Women reaching the menopause are more likely to have a single intraductal papilloma, while younger women often have more than one. 6 Phyllodes Tumour Phyllodes tumours are a rare type of breast lesion that can grow to be very large. They can affect a woman at any time in her life, but mostly occur in women between 40 and 50 years old who have not yet been through the menopause. Phyllodes tumours are usually benign but occasionally they can be malignant. They are classified into three groups: benign, borderline malignant and malignant. 7 Sclerosing Adenosis Sclerosing Adenosis is a benign condition where extra tissue grows within the breast lobules. This can cause recurring pain (which may be cyclical) or result in a small, firm lump in the breast.

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Appendix B
A description of the stage and TNM classifications of tumours. Stage 1 • • • The tumour is no more than 2 centimetres across. The lymph nodes in the armpit are not affected. The cancer has not spread.

Stage 2 • The tumour is more than 2 centimetres, but less than 5 centimetres across. • And/or the lymph nodes in the armpit are affected. • The cancer has not spread anywhere else Stage 3 • The tumour is more than 5 centimetres across • The lymph nodes in the armpit are affected • There is no further spread Stage 4 • The tumour can be any size • The lymph nodes in the armpit are often affected • The cancer has spread or metastasised to other parts of the body (for example, lymph nodes above the collar bone or distant organs such as the lungs, liver or bones) Tumour (T) T1 – The tumour is no more than 2 cm across T2 – The tumour is more than 2 cm, but no more than 5 cm across. T3 - The tumour is bigger than 5 centimetres across T4a - The tumour is fixed to the chest wall T4b - The tumour is fixed to the skin T4c - The tumour is fixed to both the skin and the chest wall T4d - Inflammatory carcinoma. This is a cancer in which the overlying skin is red, swollen and painful to the touch. Nodes (N) N0 - Nodes not involved N1 - Nodes in axilla involved but not stuck to other structures N2 - Nodes in axilla involved and stuck to each other and other structures N3 - Nodes under the breast bone (intramammary nodes) involved Metastases (M) M0 - No distant spread M1 - Spread outside the breast and local lymph glands

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Appendix C
Developing techniques to improve x-ray mammography 1 Digital Mammography Digital mammography is similar to conventional mammography in most aspects and from the patients point of view the procedure is the same. The difference is that digital mammography is equipped with a digital receptor and computer instead of a film cassette. There are two different types of detector technology that are used in digital mammography. The early systems employed indirect-conversion with a scintillator layer such as caesium iodide doped with thallium [CsI(Tl)], to capture the x-ray energy and convert it to light. An array of thin-film diodes then converts the photons to electronic signals that are captured using thin-film transistors. More recent systems however use a direct- conversion method where a The ability to view the image on a PC enables the photoconductor such as amorphous selenium (a-Se), absorbs the x-rays and directly generates the signal(Smith 2003,Yaffe 2001). radiologist to manipulate the magnification, orientation, brightness and contrast of the image to study areas in more detail. A digital mammogram and conventional mammogram of the same breast are shown in figure A.

Figure A A comparison of a digital mammogram and conventional mammogram of the same breast
(www.rk4cure.org/ images/mam.jpg)

The benefits of digital mammography over conventional mammography are that it allows easier manipulation of images for more accurate detection of breast cancer and without the need to repeat mammograms, the image processing is faster, the images can be stored and retrieved

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more easily and it is possible to send the images over telephone lines or a network for remote consultation. At present studies have indicated that the specificity of digital mammography is comparable with conventional mammography (D'Orsi 2002) although digital mammography systems currently cost four to five times more than conventional mammography. The decrease in procedural time over conventional mammography does justify this cost to some extent for a system involved in screening vast numbers of women a year, but the potential benefits in terms of breast cancer detection as opposed to extra cost are still being investigated and techniques are being improved upon. For this reason digital mammography systems are currently not widely available for routine use. 2 Computer Aided detection CAD Computer aided detection (CAD) is a recent advance in mammography which helps to identify abnormalities within the breast (website 1,Brem et al 2003). CAD technology works by reviewing digitised mammograms and marking areas of suspected abnormalities. To use the CAD technology, mammogram films are first loaded into a processing unit that digitises the mammogram images. The digital images are then run through a neural network to analyze the images and highlight abnormalities. For example a computer algorithm can be written to search for bright points that exceed a given threshold. These spots could be representative of microcalcifications and so a cluster (three or more) of these spots is identified to draw the attention of the radiographer to that area (Winn Hardin 1999). The digitised mammograms are displayed on monitors on a motorized film viewer so the radiologist can compare the original film to the digitised mammogram image on the small monitor. The radiologist reviews whether the marked areas are suspicious and require additional tests or biopsy. When using a CAD system the radiologist always makes the final interpretation of the mammogram. CAD can enhance the radiologist’s performance by drawing attention to suspicious areas that may have been missed. It can improve the rate of detection of small breast abnormalities, which increase the chances of successful treatment (Freer et al 2001). It performs consistently, reducing variability due to fatigue, distraction and workload and it reduces site-to-site variability. However, until the use of digital mammography is more widespread, it requires a lot of time and effort to digitise mammogram films. CAD currently marks a significant number of normal areas on mammograms as abnormal, which could lead to unnecessary additional breast imaging and biopsies and distracts the reporting radiologist. Furthermore CAD systems are currently very expensive.

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