Breast cancer is the commonest cancer in women and represents a significant problem from the clinical and public health perspectives. The aim of this paper is to report our experience of transitioning from screen-film mammography (SFM) to computed radiography mammography (CRM), and finally to full-field digital mammography (FFDM), and to evaluate the performance of these three different types of mammographic systems.
Breast cancer mostly arises from the glandular (dense) region of the breast. Consequently, breast density has been found to be a strong indicator for breast cancer risk. Therefore, there is a need to develop a system which can segment or classify dense breast areas. In a dense breast, the sensitivity of mammography for the early detection of breast cancer is reduced. It is difficult to detect a mass in a breast that is dense. Therefore, a computerized method to separate the existence of a mass from the glandular tissues becomes an important task. Moreover, if the segmentation results provide more precise demarcation enabling the visualization of the breast anatomical regions, it could also assist in the detection of architectural distortion or asymmetry. This study attempts to segment the dense areas of the breast and the existence of a mass and to visualize other breast regions (skin-air interface, uncompressed fat, compressed fat, and glandular) in a system. The graph cuts (GC) segmentation technique is proposed. Multiselection of seed labels has been chosen to provide the hard constraint for segmentation of the different parts. The results are promising. A strong correlation (r = 0.93) was observed between the segmented dense breast areas detected and radiological ground truth.
This paper presents an approach for breast cancer diagnosis in digital mammogram using curvelet transform. After decomposing the mammogram images in curvelet basis, a special set of the biggest coefficients is extracted as feature vector. The Euclidean distance is then used to construct a supervised classifier. The experimental results gave a 98.59% classification accuracy rate, which indicate that curvelet transformation is a promising tool for analysis and classification of digital mammograms.
Malaysia's mammography QA practice was surveyed based on the Malaysian Ministry of Health and the American College of Radiology (ACR) requirements. Data on mammography unit, processor, image receptor, exposure factors, mean glandular dose (MGD), sensitometry, image quality and viewbox luminance were obtained. Mean developer temperature and cycle time were 34.1 +/- 1.8degreesC and 107.7 +/- 33.2 seconds. Mean base+fog level, speed index and contrast index were 0.20+/-0.01, 1.20+/-0.01 and 1.33+/-0.26 respectively. Eighty-six percent of the fifty centres passed the image quality test while 12.5% complied with ACR recommended viewbox luminance. Average MGD was 1.0+/-0.4 mGy. Malaysia is on the right track for QA but with room for total quality improvement.
This paper uses wavelets in the detection comparison of breast cancer among the three main races in Malaysia: Chinese, Malays, and Indians followed by a system that evaluates the radiologist's findings over a period of time to gauge the radiologist's skills in confirming breast cancer cases. The db4 wavelet has been utilized to detect microcalcifications in mammogram-digitized images obtained from Malaysian women sample. The wavelet filter's detection evaluation was done by visual inspection by an expert radiologist to confirm the detection results of those pixels that corresponded to microcalcifications. Detection was counted if the wavelet-detected pixels corresponded to the radiologist's identified microcalcification pixels. After the radiologist's detection confirmation a new client-server radiologist recording and evaluation system is designed to evaluate the findings of the radiologist over some period of cancer detection working time. It is a system that records the findings of the Malaysian radiologist for the presence of breast cancer in Malaysian patients and provides a way of registering the progress of detecting breast cancer of the radiologist by tracking certain metric values such as the sensitivity, specificity, and receiver operator curve (ROC). The initial findings suggest that no single race mammograms are easier for wavelets' detections of microcalcifications and for the radiologist confirmation even though for this study the Chinese race samples detection average were a few percentages less than the other two races, namely the Malay and Indian races.
X-ray microradiography of surgically excised breast specimens offers the possibility of morphological characterization of calcifications. When combined with digital imaging techniques there exists added potential for obtaining valuable basic quantitative morphometric information regarding differences between microcalcifications in tissues exhibiting evidence of fibrocystic change, benign and malignant tumours. A total of 157 excised breast specimens from 84 patients were microradiographed using a Softex Super Soft X-ray unit and Kodak AA high resolution industrial film. A Quantimet 570C image analysis system was used to digitize and analyse the microradiographs. Of the 157 microradiographs, 51 (from 30 patients) revealed microcalcification clusters. The existence of significant differences between the three identified categories of tissue were indicated by clustering parameters. These included the number of particles per cluster, area of clusters, maximum distance to nearest neighbour, and geometric mean distance to nearest neighbour. The distribution pattern index (DPI), another of the clustering parameters used in this study, has been observed to be a particularly powerful discriminator. The value for fibrocystic change was found to be significantly smaller (0.514) than that for benign tumour (0.796) whilst that for benign tumour was observed to be significantly larger than that for malignant tumour (0.604) at a p-value of less than 0.05 (Kruskal-Wallis one-way analysis of variance).
INTRODUCTION: Breast cancer is the commonest female cancer in Singapore. It is steadily rising with an incidence of 53.1 cases per 100,000 persons per year among women. Screening for detection of early lesions which are highly curable helps to reduce mortality.
METHODS: Over three afternoon sessions in December 2003, 224 female patients aged 40-65 years, participated in interviews conducted by the National Healthcare Group Polyclinics, Singapore. The survey sought information on mammographic screening history, the time interval since the previous mammographic screening, and the reasons for not going for the screening.
RESULTS: The survey found that only 26.4 percent (28 out of 106) among those aged 40 to 49 years had mammographic screening done within the past one year, and 43.2 percent (51 out of 118) among those aged 50 to 65 years had screening done within the last two years. Chinese women were twice more likely than Malay women to have a mammogram done. The commonest reasons for not wanting to have mammographic screening among women who did not have a mammogram done or had mammogram done more than two years ago, were lack of time (42.5 percent), fear of pain during the procedure (26.9 percent), and the belief that cancer would not happen to them (24.6 percent).
CONCLUSION: Despite publicity on breast cancer being the commonest cancer among women in Singapore and cure being possible if the malignancy was detected early, close to half of the women aged 40-65 years old who attended the National Healthcare Group Polyclinics did not have mammographic screening done. One-quarter of the women who did not have mammogram screening did not do so as they did not think cancer would happen to them.
Study site: NHG Polyclinics, Singapore
BACKGROUND: Mammographic density is a strong risk factor for breast cancer. Apart from hormone replacement therapy (HRT), little is known about lifestyle factors that influence breast density.
METHODS: We examined the effect of smoking, alcohol and physical activity on mammographic density in a population-based sample of postmenopausal women without breast cancer. Lifestyle factors were assessed by a questionnaire and percentage and area measures of mammographic density were measured using computer-assisted software. General linear models were used to assess the association between lifestyle factors and mammographic density and effect modification by body mass index (BMI) and HRT was studied.
RESULTS: Overall, alcohol intake was positively associated with percent mammographic density (P trend = 0.07). This association was modified by HRT use (P interaction = 0.06): increasing alcohol intake was associated with increasing percent density in current HRT users (P trend = 0.01) but not in non-current users (P trend = 0.82). A similar interaction between alcohol and HRT was found for the absolute dense area, with a positive association being present in current HRT users only (P interaction = 0.04). No differences in mammographic density were observed across categories of smoking and physical activity, neither overall nor in stratified analyses by BMI and HRT use.
CONCLUSIONS: Increasing alcohol intake is associated with an increase in mammography density, whereas smoking and physical activity do not seem to influence density. The observed interaction between alcohol and HRT may pose an opportunity for HRT users to lower their mammographic density and breast cancer risk.
Breast recurrence of acute lymphoblastic leukaemia (ALL) after stem cell transplant is uncommon, with less than 20 reported cases in the literature. In the majority of cases, the lesions developed without simultaneous involvement of other sites or graft-versus-host disease (GvHD). We describe the first case of simultaneous bilateral breast and ovarian relapses after allografting in ALL, occurring in an 18-year-old female Chinese patient while she was having oral and hepatic chronic GvHD, persistent haematological remission and donor haematopoiesis. She received radiotherapy and chemotherapy, which resulted in resolution of the breast and ovarian lesions, and remained disease free ten months after the onset of the relapse. This case suggests that there may be different mechanisms for bone marrow vs. extramedullary relapses and a complex relationship between GvHD and graft-versus-leukaemia.