Of all 61 MDCT- or MRI-detected lesions, 58 (95.1%) in 53 patients were identified by targeted sonography. Pathologic diagnoses were obtained in 45 lesions, and we followed up 13 lesions. A status of study lesions is shown in Figure .
As for the 53 patients, the age and menopausal status of the pathologically confirmed group and the follow-up group are shown in Table . Patients in the pathologically confirmed group were significantly older and more likely to be postmenopausal than those in the follow-up group. There were no significant differences in the follow-up period between the two groups (Table ).
Patient characteristics (53 patients, 58 US-identified lesions)
Example images of MDCT and targeted sonography are shown in Figures , and . Figure shows a suspicious lesion in the ipsilateral breast, and it is more than 3
cm distant from the main lesion. MDCT shows linear enhancement surrounded by fat tissues, while targeted sonography depicts a hypoechoic lesion in the atrophic thin breast with a size of 14 x 2
mm and abundant fat tissues surrounding the lesion. Ductal carcinoma in situ (DCIS) was suspected on the MDCT and ultrasonography image findings. It is often difficult to keep the lesion visible during an ultrasound-guided biopsy. We made an excision after marking on the skin of the lesion under ultrasound. The pathologic finding of this lesion was DCIS.
Figure 2 MDCT showed segmental enhancement on the ipsilateral breast. An enhanced lesion was depicted in the thin breast gland. Targeted sonography detected a hypoechoic lesion in the thin breast gland, the size of which was 14x2 mm. Excisional biopsy was performed (more ...)
Figure 3 MDCT showed clustered enhancement on the ipsilateral breast. Targeted sonography detected a hypoechoic lesion, but it was difficult to differentiate the surrounding tissue. An excisional biopsy was performed at the same time as breast lumpectomy to obtain (more ...)
Figure 4 MDCT showed enhanced focus on the contralateral breast. Targeted sonography showed a hypoechoic mass connecting to the adjacent ducts, the size of which was 5x2 mm. Sonography-guided vacuum-assisted core needle biopsy was performed to obtain a definitive (more ...)
Figure shows a clustered enhanced lesion in the ipsilateral breast on MDCT. The lesion was 1.5
cm distant from the nipple lower outer quadrant in the breast on the MDCT. Targeted sonography showed a faintly hypoechoic lesion as an enhanced area. We excised it simultaneously with performing a lumpectomy of the known breast cancer after sonographically guided marking because it was located in a difficult place to perform sonographically guided biopsy. The pathologic finding of the lesion was columnar cell hyperplasia.
Figure showed a well-demarcated enhanced tumor in the thin breast tissue which was 1.5
cm distant from the nipple on the inner side. The tumor size was 5 × 2
mm. Targeted sonography depicted a hypoechoic mass in the atrophic breast and sonographically guided biopsy was performed under ultrasound guidance. The pathologic finding was hyperplasia.
Sonography-guided fine needle aspiration was performed in 22 lesions, and a pathologic diagnosis was made in 45 lesions. Of the 22 lesions, fine needle aspiration cytology was benign or normal in 7, inadequate in 7, indeterminate in 2, suspicious for malignancy in 1, and malignant in 5. For a pathological diagnosis, 30 lesions underwent sonographically guided biopsy, while 9 lesions underwent surgical biopsy during and before the operation, 5 lesions had extended excisional ranges, and one underwent core needle biopsy.
Pathologic examinations revealed benign in 20 (44%) lesions and malignant in 25 lesions (56%), including one lesion diagnosed as cancer at another hospital. Of the 20 benign tumors pathologically diagnosed in our hospital, 7 were hyperplasia, 5 were intraductal papillomatosis, 3 were fibrocystic change, 2 were fibroadenoma and one was adenoma. Proliferation was not found in 2 lesions with discharge in the dilated duct. Of 25 malignant tumors, DCIS was found in 13 and invasive ductal carcinoma in 12 (Table ). The mean follow-up period (SD) of 56 patients was 940.2 (553.1) days.
Pathologic findings in 45 lesions
The maximum diameter of the detected lesions as determined by targeted sonography is shown in Table . The maximum diameter was under 5.0
mm in 26 lesions, 5.1-10.0
mm in 25 lesions, 10.1-15.0
mm in 6 lesions, and over 15.1
mm in one lesion. The mean (SD) of the maximum tumor size was 6.5 (3.8) mm. As the lesion over 15.1
mm was suspected to be present in the image of one patient, we measured the size of the hypoechoic lesion. There were no significant differences in size among the malignant, benign and follow-up groups (Table ).
Maximum tumor size of the lesion detected by targeted sonography
As shown in Table , the numbers of lesions with depth:width ratios under and over 0.7 were 45 and 13, respectively. There were no significant differences in the depth:width ratio in the three groups (Table ).
Depth:width ratio of the lesion detected by targeted sonography
Based on our experience, we developed a diagnostic imaging strategy for MDCT- or MRI-detected lesions in breast cancer (Figure ).
Diagnostic Imaging Strategy for MRI- or MDCT-Detected Lesions.