Various kinds of modalities have been used to detect and diagnose breast cancer. In order to detect early breast cancer, mass screening has been widely performed with physical examinations in Japan and mammography in the U. S and European countries. After detecting some abnormalities within the breast under basic screening, further examinations are required for a precise diagnosis. For this purpose, ultrasonography and/or thermography are used as a noninvasive image examination, and aspiration biopsy cytology and/or surgical biopsy are employed for the final diagnosis. Mammography with highly qualified equipment and its adequate performance is thought to be the most useful modality in basic screening for detecting nonpalpable breast cancer. Ultrasonography is valuable for differentiating whether the lesions detected on screening are malignant or benign. Thermography seems better in analysing the malignant potential of the lesions detected by other examinations. Aspiration biopsy cytology (ABC) is employed for final diagnosis. Fine needle ABC has the highest sensitivity (90.8%) compared to other modalities in this department of Fukushima Medical College Hospital. Positive diagnosis on ABC is not needed for surgical biopsy. However, suspected or negative findings on ABC are required for two-step surgical biopsy which should be performed at the outpatient clinic to obtain detailed information about the biological characteristics as well as pathological diagnosis.