Takayoshi Uematsu

Three-Dimensional Helical CT of the Breast: Accuracy for Measuring Extent of Breast Cancer Candidates for Breast Conserving Surgery

AbstractObjective. To evaluate the accuracy of three-dimensional (3D) helical computed tomography (CT) for assessing the extent of breast cancer of candidates for breast conserving surgery.nMethods. Results of helical CT were studied in 144 lesions of 144 patients with breast cancer before breast-conserving surgery. A lesion was defined as positive if focal enhancement was detected by CT within 100s after contrast material administration. After resection, tumors were histopathologically mapped and correlated with the extent of 3D images.nResults. Helical CT enabled detection of 143 tumors but not of one ductal carcinoma in situ (DCIS). The median deviation of the tumor extension revealed by 3D helical CT images from pathological assessment was 7.7mm (range 0–60mm). The extent of tumors was significantly correlated with CT measurements (r=0.714, p<0.0001). By multivariate analysis, the presence of invasive tumors with intraductal extensions beyond the edge of the invasive tumor and histologic type (DCIS) were significant risk factors for deviation of the tumor extension revealed by 3D helical CT images from pathological assessment.nConclusion. Three dimensional helical CT of the breast is an accurate preoperative imaging modality for assessing the extent of breast cancer candidates for breast conserving surgery.

Staging of palpable tl-2 invasive breast cancer with helical ct

BackgroundThe purpose of this study was to evaluate the accuracy of contrast-enhanced high resolution helical computed tomography (CT) for assessing locoregional staging of palpable Tl-2 invasive breast cancer. Methods: Helical CT studies of 156 lesions from 156 patients with invasive breast cancer before breast-conserving surgery were examined. A lesion was defined as positive if focal enhancement was detected by CT within 100 seconds after contrast material administration. After resection, tumors were histopathologically mapped and comparison made with the extent of contrast enhancement.ResultsHelical CT enabled detection of all 156 index tumors. CT enabled detection of 28 of 43 multifocal lesions (65%) and five of five multicentric lesions (100%). In 24 of 33 lesions (73%), CT revealed additional cancers not seen on mammography. The extent of tumor significantly correlated with CT measurements (r=0.76,p<0.0001).ConclusionHelical CT of the breast is an accurate preoperative imaging modality for assessing the locoregional staging of Tl-2 invasive breast cancer.

False-positive helical CT findings of multifocal and multicentric breast cancer: is attenuation of tumor useful for diagnosing enhanced lesions?

ObjectiveTo analyze helical CT false-positive multifocal breast cancers and to assess the relevance of the attenuation of tumors for diagnosing enhanced lesions.MethodsHelical CT studies of 156 invasive breast cancers before breast conserving surgery were examined. A lesion was defined as positive if focal enhancement was detected by CT within 100 seconds after contrast material administration. The attenuation and enhancement percent ratio [(post-contrast value/pre-contrast value)%] were obtained. Attenuation of false-positive and malignant lesions was compared.ResultsHelical CT enabled the detection of all 156 invasive tumors with 95 intraductal tumor extensions. The sensitivity and specificity of multifocal/multicentric disease detection by helical CT were 69% and 90%, respectively. False-positive multifocal/multicentric findings were obtained in 11 (7%) of 156 cases. The mean value of the enhancement percent ratio of the index tumors was 237%. Significant differences in the attenuation on post-contrast enhanced scans between the enhanced lesions (index tumors; mean, 82 HU), the true-positive multifocal/multicentric lesions (mean, 73 HU), the false-positive multifocal/multicentric lesions (mean, 87 HU) and normal breast tissue (mean, 32 HU) were found (p < 0.0001). The attenuation of the true-positive multifocal/multicentric lesions on post-contrast enhanced scans was significantly less than that of the false-positive multifocal/multicentric lesions (p = 0.03).ConclusionAttenuation of tumor is not useful for differential diagnosis of enhanced lesions on helical CT of the breast. The presence of enhancement alone does not always indicate a malignant lesion. Breast Cancer 9:62-68, 2002.

Value of Three-Dimensional Helical CT Image-Guided Planning for Made-to-Order Lumpectomy in Breast Cancer Patients.

Abstract:u2003 The authors reviewed Niigata Cancer Center Hospitals experience treating patients with lumpectomy to evaluate the utility of three‐dimensional helical computed tomography (3D‐CT) image‐guided made‐to‐order lumpectomy and determine a positive margin rate. From April 1993 to September 2000, 251 breasts in 248 patients were treated with lumpectomy with a 1 cm macroscopic free margin. In 213 breasts (85%), 3D‐CT image‐guided made‐to‐order lumpectomy was performed. Thirty‐eight breasts (15%) underwent a lumpectomy without 3D‐CT. The lumpectomy specimen was sectioned at 5 mm intervals. Margin status was classified as negative (no invasive or ductal carcinoma in situ (DCIS) within 2 mm from the cut surface) or positive. Positive margins were classified as focally positive (invasive or DCIS transected at the margin within 5 mm or one slide) or massively positive. With 3D‐CT image‐guided Iumpectomy, 21% (45/213) of lesions had a positive margin and 42% (16/38) of lesions without 3D‐CT image‐guided lumpectomy had a positive margin (p = 0.0055). For lesions with massively positive margins, the rates were 9% (4/45) for 3D‐CT image‐guided lumpectomy and 38% (6/16) for lumpectomy without 3D‐CT (p = 0.0152). 3D‐CT image‐guided made‐to‐order lumpectomy decreased the positive surgical margin rate. Among patients with positive margins, those with 3D‐CT image‐guided lumpectomy have less residual cancer than those without 3D‐CT.

Digital mammographic screening in Japan

We describe the current status of mammographic screening and investigate how digital mammography is used in screening in Japan. Despite the widespread use of digital mammographic equipment, the mammographic screening rate for invited women is very low. In the majority of cases, digital hard copy images are read for screening. Soft-copy reading of digital mammography is not widely used, because of the difficulty of handling large amounts of CR data, the cost of workstations with 5xa0M LCD monitors, and the loading of full-field digital mammography on the mobile unit. Digital mammography has a number of advantages and has increasingly replaced conventional film-screen mammography, becoming the gold standard in combination with soft-copy reading in screening settings.