D. David Dershaw

OBJECTIVE: The purpose of the study was to assess the positive predictive value of mammographic features and final assessment categories described in the Breast Imaging Reporting and Data System (BI-RADS) for lesions on which biopsies have been performed. SUBJECTS AND METHODS: We prospectively evaluated 492 impalpable mammographically detected lesions on which surgical biopsy (as opposed to percutaneous biopsy) was performed. Each lesion was classified according to BI-RADS descriptors for masses (margins and shape) and calcifications (morphology and distribution) and was categorized by the BI-RADS final assessment categories as category 3 ("probably benign"), category 4 ("suspicious abnormality"), or category 5 ("highly suggestive of malignancy"). Mammographic and pathologic findings were reviewed. RESULTS: Carcinoma was present in 225 (46%) of 492 lesions. For the 492 lesions subject to biopsy, BI-RADS final assessment categories were category 3 in eight lesions (2%), category 4 in 355 (72%), and category 5 in 129 (26%). The features with highest positive predictive value for carcinoma were spiculated margins (81%), irregular shape (73%), linear calcification morphology (81%), and segmental or linear calcification distribution (74% and 68%, respectively). Carcinoma was present in 105 (81%) of 129 category 5 lesions compared with 120 (34%) of 355 category 4 lesions (p < .001). The frequency of carcinoma was higher in category 5 than in category 4 lesions for all mammographic lesion types and all interpreting radiologists. CONCLUSION: The standardized terminology of the BI-RADS lexicon allows quantification of the likelihood of carcinoma in an impalpable breast lesion. The features with highest positive predictive value--spiculated margins, irregular shape, linear morphology, and segmental or linear distribution--warrant designation of a lesion as category 5.

OBJECTIVE: The purpose of this study was to review MR imaging findings in the ipsilateral breast in women with percutaneously proven breast cancer. MATERIALS AND METHODS: Retrospective review was performed of records of 70 consecutive women with percutaneously proven unilateral breast cancer who were considered candidates for breast conservation surgery and who had preoperative MR imaging of the ipsilateral breast. MR images and medical records were reviewed. RESULTS: MR imaging identified mammographically and clinically occult cancer other than the index lesion in the ipsilateral breast in 19 women (27%), including infiltrating cancer in 11 women (16%) and ductal carcinoma in situ in eight women (11%). These additional sites of cancer were in the same quadrant as the index cancer in 14 women (20%), in a different quadrant in three women (4%), and in both the same and different quadrants in two women (3%). Additional sites of cancer were more likely in women with, rather than in those without, a family history of breast cancer (42% vs 14%, p < 0.02) and in women whose index cancer was infiltrating lobular rather than other histologies (55% vs 22%, p < 0.06). In 17 women (24%), MR imaging detected ipsilateral lesions that were benign. Changes due to prior percutaneous biopsy were infrequently observed on MR images and included a clip in 12 women (17%) and a small hematoma in two women (3%). CONCLUSION: MR imaging identified additional sites of ipsilateral cancer in 27% of women with percutaneously proven breast cancer. The yield was highest in women with a family history of breast cancer or infiltrating lobular histology in the index cancer. Change after biopsy was infrequent and did not interfere with the MR imaging interpretation.

OBJECTIVE: The purpose of this study was to determine the frequency of cancer and the positive predictive value of biopsy in the first screening round of breast MRI in women at high risk of developing breast cancer. MATERIALS AND METHODS: Retrospective review was performed of the records of 367 consecutive women at high risk of developing breast cancer who had normal findings on mammography and their first breast MRI screening examination during a 2-year period. The frequency of recommending biopsy at the first screening MRI study and the biopsy results were reviewed. RESULTS: Biopsy was recommended in 64 women (17%). Biopsy revealed cancer that was occult on mammography and physical examination in 14 (24%) of 59 women who had biopsy and in 14 (4%) of 367 women who underwent breast MRI screening. Histologic findings in 14 women with cancer were ductal carcinoma in situ in eight (57%) and infiltrating carcinoma in six (43%). The median size of infiltrating carcinoma was 0.4 cm (range, 0.1-1.2 cm). Two patients had nodes that were positive for cancer. Biopsy revealed high-risk lesions (atypical ductal hyperplasia, atypical lobular hyperplasia, lobular carcinoma in situ, or radial scar) in 13 (4%) of 367 women and other benign findings in 32 (9%) of 367 women who had MRI screening. CONCLUSION: Among women at high risk of developing breast cancer, breast MRI led to a recommendation of biopsy in 17%. Cancer was found in 24% of women who underwent biopsy and in 4% of women who had breast MRI screening. More than half the MRI-detected cancers were ductal carcinoma in situ.

PURPOSE: To determine the frequency with which ultrasonographically (US) guided core biopsy obviated diagnostic surgical biopsy of nonpalpable breast masses, to calculate the cost savings of diagnosis attributable to US-guided core biopsy, and to compare the costs of US-guided versus stereotactically guided core biopsy. MATERIALS AND METHODS: US-guided core biopsy was performed in 151 consecutive solitary, nonpalpable breast masses in 151 women (age range, 23-80 years) by using a 14-gauge automated gun and needle. Clinical follow-up data were obtained. Cost savings were assessed by using national Medicare reimbursement costs of +385 for US-guided core biopsy, +610 for stereotactic core biopsy, and +1,332 for needle localization and surgical biopsy. RESULTS: US-guided core biopsy obviated a surgical procedure in 128 (85%) of 151 women. The mean adjusted direct cost saving per US-guided core biopsy was +744 per case. Use of US-guided biopsy decreased the cost of diagnosis by 56% (+744/+1,332) over the cost of surgical biopsy. If biopsy had been performed with stereotactic rather than with US guidance, the mean adjusted direct cost saving would have been +519 per case, a 39% (+519/1,332) decrease in the cost of diagnosis compared with the cost of surgical biopsy. CONCLUSION: Percutaneous biopsy of a nonpalpable breast mass with either US or stereotactic guidance is less expensive than surgery, but cost savings are greater with US-guided biopsy.

Multidisciplinary guidelines for management of invasive breast carcinoma from the American College of Radiology, the American College of Surgeons, the College of American Pathology, and the Society of Surgical Oncology have been updated to reflect the continuing advances in the diagnosis and treatment of invasive breast cancer. The guidelines provide a framework for clinical decision-making for patients with invasive breast carcinoma based on review of relevant literature and include information on patient selection and evaluation, technical aspects of surgical treatment, techniques of irradiation, and follow-up care.