There was high interest in breast imaging at the American Roentgen Ray Society Meeting. Research papers and categorical courses generally focused on outcome and management after percutaneous core needle biopsy, breast MRI, malpractice issues, and computer-aided diagnosis. During the categorical courses, many questions arose from participants in general radiology practices about the application of new technologies, specifically MRI and computer-aided detection. In particular, more and more practices are using contrast-enhanced breast MRI for cancer detection, but are running into problems regarding small lesions that are not completely characterized. One of the solutions proposed involved using ultrasound, targeted to the MRI-detected lesion, to further localize the abnormality.

The Scientific Session on breast ultrasound included papers 15-22. Research concentrated on the use of harmonic imaging and SonoCT compound imaging, a technique which obtains multiple coplanar, tomographic ultrasound images. These multiple images are then combined into a single compound image. Both techniques are used to reduce acoustic artifacts and noise. Paper 16 showed that SonoCT compound imaging improved evaluation of solid breast nodule margins. These investigators found, however, that the use of SonoCT compound imaging did not preserve posterior acoustic artifacts (which can be helpful in diagnosis) leading to a recommendation that solid breast nodules be assessed by a combination of both conventional and compound imaging. In other abstracts (Paper 18) harmonic imaging was thought to improve evaluation of both breast cysts and breast nodules.

Regarding ultrasound-guided biopsy using directional vacuum-assisted needles, two abstracts (Papers 19 & 20) showed that the technique is useful in removing small breast lesions. These researchers reported complete removal in 55% of cases (Paper 19, n=61) and 89% of cases (Paper 20, n=60). However, the latter group showed an immediate complication rate of 10% with four "cutaneous holes" and two cases of arterial bleeding. In the same study, an additional five patients had pain (relieved by Tylenol) and another two patients had subsequent hematoma. This study shows that the complication rate with the vacuum-assisted devices under ultrasound guidance is higher than with the automated devices.

Scientific Session 17, on stereotactic-guided biopsies (papers 131-140), concentrated on follow-up and patient management after core biopsy. Papers 134, 135 and 136 re-emphasized the need for excisional biopsy after the finding of atypical ductal hyperplasia on core biopsy histology. An interesting spin on core histology was the finding of positive cytokeratin 903 (CK903) in benign lesions (Paper 135). When CK903 was found in patients with atypical ductal hyperplasia, a subsequent excisional biopsy showed only benign lesions. In contrast, malignant lesions showed a loss of CK903 staining on their histology. This study identifies a potential role of CK903 expression in benign biopsies that may obviate the need for excisional biopsy in patients with atypical ductal hyperplasia. The authors stressed, however, that these preliminary results would have to be confirmed in subsequent studies.

Another interesting study (Paper 138) showed that the presence of mucin in large-core needle biopsies does not always represent mucinous carcinoma. The authors presented 20 patients showing mucin on large-core needle biopsies (17 clusters of calcifications, three masses). Large-core needle biopsies with extravasated mucin were cancerous on surgical incisional biopsy only when atypia was found in the original large-core needle biopsy histology. In the absence of atypia, there was less chance for mucinous carcinoma or other types of malignancy at incisional biopsy.

Scientific Session 24 on outcomes research and breast MRI (papers 190-197) showed improved mammographic interpretations of calcifications after training in BIRADS (Paper 192) with increased accuracy in recommendations for biopsy. An interesting paper, evaluating outcomes after biopsies positive for LCIS (Paper 195), showed that 10% of women in the study (5 of 48) developed breast cancer over a mean length of observation of 62 months. Three patients (6%) had ipsilateral DCIS and two patients developed contralateral cancer (one invasive ductal cancer, one DCIS). The DCIS was found by mammography and the invasive cancer was detected by physical examination. This shows that early breast cancer can be detected by mammography and physical examination during surveillance after a diagnosis of LCIS. An MRI paper (Paper 197) showed that dynamic MRI was able to detect breast cancer in women with silicon breast implants. Another MRI talk (Paper 196) showed the use of contrast enhanced MR at 0.5 Tesla produced a sensitivity and specificity for malignancy of 95%, and a specificity for benign lesions of 80%.

Scientific Session 29 concentrated on computer digital mammography and ultrasound and radiological imaging of the breast and breast specimens. Two evaluations of digital mammography (Papers 230 and 231)pointed out a decrease in examination time for the digital imaging because no film processor was used. Full field digital mammography acquisition time was 7.3 minutes +/- 17.2 minutes; shorter than for film screen mammography at 12.6 minutes ( film screen acquisition times included mammogram acquisition time of 7.4 minutes and processing of 3.2 minutes). Recall rates for the analog and the digital examinations were 6.7 and 5.7%, respectively, over the 1,000 cases.

The ARRS meeting showed that patient management after core biopsy is still a challenging dilemma when treating women with atypical ductal hyperplasia and LCIS. Some researchers are looking to tissue markers to help with management decisions. Also, despite the advent of CAD as a "helper" to the radiologist in abnormality detection, radiologists still have fears about potential malpractice issues. The balance between these fears and the benefit of computerized technology will most likely be the subject of discussion and research for many years to come.