The incidence of breast cancer in Thai women increased significantly each year. The statistic from Siriraj Cancer Institute, it was 6.8% of female cancers in 1985 and became 20.0% in 2003. With increasingly use of hormone replacement therapy in Thai ladies, awareness of breast cancer is mandatory. Screening for breast cancer is recommended prior to and during the treatment. Thai breasts are differed in the composition of breast tissue. It was almost entirely fat in 2527 cases (7%), scattered fibroglandular in 7216 cases (20%), heterogeneously dense in 21498 (59%) and extremely dense in 5146 cases (14%).Therefore, in our practice, no matter it is a screening or diagnostic case, we performed mammography first, we looked at the films and finished the Siriraj Breast Centre had mammograms performed in 39,806 cases (up to July 2004), which was for screening in 22,468 cases (56.44%) and for diagnosis in 17338 cases (43.56%). Of the screening cases, we
made diagnosis of benign looking lesions (BIRADS 2) in 24.35%, probably benign (BIRADS 3) in 17.02%, indeterminate lesion (BIRADS 4) in 2.23% and malignancy (BIRADS 5) in 79 cases (0.35%).
Of those 79 cases, mass was noted in 43 cases, microcalcifications alone in 19 cases and mass with
microcalcifications in 22 cases.
The ultrasound can detect malignancy in mammography negative in 141 cases. The correlation of mammographic, ultrasonic and pathological diagnoses will be presented and the analysis confirms significantly increased accuracy when both mammograms and ultrasound are practiced together, mammographic study and then, we scanned the patient by ultrasound. When a mass is found by mammograms, it is defined into a round or oval mass or a microlobulated, irregular or speculated mass. Ultrasound can show more details of the mass. We give the impression of a simple cyst, complex cyst, benign looking solid mass, probably benign solid mass, indeterminate nature or highly suggestive of malignancy. Ultrasound is very beneficial in detection of the vascularity of the mass and guidance for breast intervention (core needle biopsy, fine needle aspiration, cyst aspiration and needle localization, etc.) The procedure is easy and quick, showing the exact needle tip at real-time. When microcalcifications are presented, mammography is extremely valuable. The distribution and the individual character of microcalcifications can be determined, leading to accurate diagnosis. Ultrasound
is almost no clinically useful, unless they are abundant and extremely high frequency, high-resolution transducer is available. In certain cases, we use US guidance in such lesions, but normally, we use stereotactic guidance. Other findings are also beneficial and will be discussed.

Keywords: Breast, HRT