The management of breast cancer has changed over the last century, with surgeries becoming less invasive and adjuvant therapies becoming indispensible. Sentinel lymph node biopsies (SLNB) have replaced axillary nodal dissections as a method of staging an axilla in early breast cancer. However, 70% of SLNBs are negative. The aim of this study was to determine if wecould decrease the rate of negative sentinel lymph node biopsies? A retrospective review over a 10 month period was undertaken. Patients undergoing a SLNB and who had a documented negative axillary ultrasound report were included. One hundred and fifty onepatients were eligible for inclusion. Patients’ ultrasound reports and initial biopsy specimen characteristics (ER/PR/Her2-neu, LVI, Grade, Location) were compared to their axillary nodal findings on histology. An ultrasound was able to predict a pathologically negative axilla in 71.6% of patients. Exclusion of micrometastasis increased the negative predictive value to82.8%. If the ultrasound was negative in a histologically positive axilla, it was likely that only 3 or less nodes were involved. Nodal metastasis could not be predicted based on the tumour characteristics that were reported on the initial tumour biopsy specimens(ER/PR/Her2- neu, LVI, Grade, Location). LVI and DCIS on the initial biopsy specimens were poorly correlated with the final histology specimen findings.. The results show that an ultrasound cannot currently replace a SLNB as an accurate means of evaluating an axilla. A clear limitation is the inability to detect micrometastasis, however the role of micrometastasis in axillary staging is diminishing. Ultrasonographic evaluation of the axilla is currently reported in a non-standardised manner. Classification systems do exist, and if applied to current reporting will increase the negative predictive value of ultrasonography. In the future, the combination of improved reporting standards of axillary ultrasounds, as well as the surgical conservatism with regard to the management of micrometastasis and small volume metastasis in the axilla will hopefully reduce the rate of negative SLNB’s.

A research report submitted to the Faculty of Medicine, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Medicine in Nuclear Medicine. / Forty (40) female patients with breast masses underwent Technetium 99m Sestamibi scintigraphy in order to evaluate its usefulness in differentiating benign from malignant breast disease and to compare scintigraphy to mammography. Informed consent was obtained from each patient. Scintigraphy consisted of anterior chest and lateral and oblique breast planar images, obtained 5 minutes after intravenous injection of 20 rnecuries (740 MBq) Technetium 99m Sestamibi. Eleven (11) of the 40 patients also had Technetium 99m Methylene Diphosponate breast scintigraphy for comparison. Four nuclear medicine physicians of who three also graded the MDP images performed grading of the Sestamibi scintigraphic images. The grading method, although focussing on the absence (0) or presence (>0) of uptake of isotope, was also designed for comparison of the Sestamibi and MDP images. Statistical analysis showed good correlation between observer grading. Breast scintigraphy was compared to mammography in 27 ofthe 40 patients. Of the 26 malignant breast masses confirmed on histology, 19 were positively identified on Sestamibi scanning giving a sensitivity of 73%, 2 results were inconclusive (grading (0·1) and 5 had a grading 0, of the 8 patients with confirmed lymph node metastases, only 2 were positive on the Sestamibi scans, with 1 inconclusive result. Of the 19 benign breast masses, 9 were visible on Sestamibi scans with additional 3 inconclusive results (grading of 0-1). Statistical analysis showed no significant difference in the Sestamibi and MDP grading. In comparison to mammography, breast scintigraphy was less accurate in distinguishing benign from malignant breast masses. Mammography identified 85.7% of the malignant breast masses and 72.7% of the benign breast masses. Sestamibi scintigraphy identified 76.2% of the malignant breast masses and only 36.4% of the benign breast masses. / Andrew Chakane 2018

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Medicine in Diagnostic Radiology Johannesburg, 2013 / Palpable solid breast masses that are circumscribed and not calcified on mammogram or ultrasound are probably benign. There is controversy therefore, whether these deserve tissue diagnosis. More data is required to determine whether short term follow up can replace the need for biopsy. Benign appearing lesions greater than 3cm in diameter on ultrasound continue to undergo biopsy due to fear that a malignancy or phyllodes tumour might be missed. Published research reflects patients from Europe and North America, and no relevant data from Africa exists. AIM: This study aims to determine the histological spectrum of sonographically benign lesions greater than 3cm, which were biopsied, in our local population (majority of black patients) and to determine whether biopsy is indicated based on the local cancer risk. The study also aims to characterise the results by age and population group as well as correlate the histological result with the size of the lesion on ultrasound, the HIV status, family history and the seniority of the examining radiologists. MATERIALS AND METHODS: A retrospective descriptive study of biopsy results of sonographically benign breast masses was undertaken using biopsy procedural recording sheets. . The size of the lesions (continuous variables) mean with standard deviations was determined. The prevalence of lesions was expressed as a percentage. Other categorical variables were summarized as frequency and percentage. The vi histological spectrum of the lesions was determined. The HIV status and family history of the patients as well as the seniority of the reviewing radiologist was assessed. A Krusskal Wallis test and separate logistic regression analysis was used. RESULTS: A total of 68 patients (below 40 years of age) were included from a total of 13112 patients (of all ages) seen between 2007 and the end of 2010. 73 lesions were identified (65 benign and 8 malignant). The prevalence of benign lesions was 89.7%. .The prevalence of malignant lesions was 10.29%.There was little evidence to support lesion size for predicting histology (p value = 0.22) or benignity. There was little evidence that the family history and HIV status were significant. CONCLUSION: There was a high prevalence (10.29%) of malignancies in lesions classified by ultrasound as benign. The size of the lesion did not correlate with histological subtype or whether the lesion was benign or malignant. Training of sonographers, standardization of technique for established users and double reading, may produce a different result, as both junior and senior radiologists mistook malignant lesions for benign ones on ultrasound. Repeating this research using double reading after training may demonstrate whether there is a true higher prevalence of malignancy in ultrasonically benign breast lesions in our community. Until then, routine biopsy of these lesions is recommended.

Electrical parameter profiles of human breast images can be used to simulate and analyze the anticipated effects on tissue from its interaction with electromagnetic fields involved in the cancer treatment exposure. In part, the success of this approach depends on the accuracy and precision in identifying the different tissue types. In this work, we propose two methods of segmenting human breast images with malignant tumors. The first method of algorithmic partitioning of the image involves manual color-edge contouring of the tissues using a cursor and subsequent identification of the tissue types. For the second method, MRI T1 values and thresholds are used to perform segmentation and we investigate the potential of incorporating edge detection. The first method is effective, while the second lacks precision, but eliminates the need of manual contouring. The images are imported as BMP files into SEMCAD, an electromagnetic simulation tool based on finite-difference time-domain method, which recognizes the grouped tissues and creates a model of the image. The model allows the user to easily assign electrical parameter values to the grouped tissues, according to the measured values reported in the literature.

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CAPES / Em vista do grande número de casos de câncer de mama e sua crescente taxa de incidência, novas técnicas de imagem estão sendo estudadas. No intuito de proporcionar melhores condições de visualização e detecção dessa doença, em complemento às informações obtidas por mamografia, as técnicas de imagem por contraste de fase vêm sendo investigadas. Assim, o objetivo do presente estudo, foi desenvolver um phantom de mama para aplicação em imagens por contraste de fase. Este phantom, é um cilindro com algumas inserções preenchidas por materiais equivalentes a tecidos mamários normais e patológicos, como: polimetilmetacrilato (PMMA), água, etanol, dimetilformamida e glicerol. Estes materiais foram escolhidos pela similaridade nas propriedades de atenuação e espalhamento dos tecidos mamários. Dentre as técnicas para evidenciar contraste de fase, foi utilizada a técnica de propagação. O arranjo experimental foi elaborado levando em consideração os cálculos para obtenção do contraste de fase utilizando a instrumentação para microtomografia de raios X do Instituto Lactec. Imagens radiográficas e microtomográficas foram adquiridas por transmissão e por contraste de fase e posteriormente comparadas. A comparação entre as imagens analisadas apresentaram significativas melhoras no contraste, principalmente nas bordas dos cilindros presentes no phantom. Portanto, o phantom desenvolvido neste trabalho pode ser utilizado para otimizar os parâmetros de aquisição e tratamento de imagens por contraste de fase para aplicação na detecção do câncer de mama. / Because of the large number of cases of breast cancer and its increasing incidence rate, new techniques of imaging are being studied. With the aim to provide better conditions for visualization and detection of this disease, in complement of the information obtained by mammography, the techniques of phase contrast imaging have been studied. Thus, the objective of the present study was to develop a breast phantom for application in phase contrast images. This phantom is a cylinder with some inserts filled with equivalent materials to normal and pathological breast tissues, such as: polymethylmethacrylate (PMMA), ethanol, dimethylformamide and glycerol. These materials were chosen due to the similarity in the attenuation and scattering properties of breast tissues. Among the techniques to demonstrate phase contrast, it was used the propagation technique. The experimental arrangement was elaborated taking into account the calculations to obtain the phase contrast using the instrumentation for X-ray microtomography of the Lactec Institute. Radiographic and microtomographic images were acquired by transmission and by phase contrast and then compared. The comparison between the analyzed images showed significant improvements in the contrast, mainly in the edges of the cylinders present in the phantom. Therefore, the phantom developed in this work can be used to optimize the acquisition and treatment parameters of phase contrast images for application in the detection of breast cancer.