MR-directed ("Second-Look") ultrasound examination for breast lesions detected initially on MRI: MR and sonographic findings.

OBJECTIVE: The objective of our study was to assess the clinical utility of MR-directed ("second-look") ultrasound examination to search for breast lesions detected initially on MRI. MATERIALS AND METHODS: A retrospective review was performed of the records of 158 consecutive patients (202 lesions) with breast abnormalities initially detected on MRI between July 2003 and May 2006. All lesions were detected as enhancing findings on a dynamic contrast MR study and were subsequently evaluated with ultrasound. Ultrasound was performed using MR images as a guide to lesion location, size, and morphology. Pathology findings were confirmed by subsequent percutaneous biopsy or lesion excision. Imaging follow-up was used for probably benign lesions, which were not biopsied. RESULTS: Of the 202 MRI-detected lesions, ultrasound correlation was made in 115 (57%) including 33 malignant lesions and 82 benign lesions. The remaining 87 lesions were not sonographically correlated and included 11 malignant lesions and 76 nonmalignant lesions. Mass lesions identified on MRI were more likely to have a sonographic correlate than nonmasslike lesions (65% vs 12%, respectively); malignant mass lesions were more likely to show an ultrasound correlation (85%). The malignant lesions with successful sonographic correlation tended to present with subtle sonographic findings. CONCLUSION: MR-directed ultrasound of MRI-detected lesions was useful for decision making as part of the diagnostic workup. Malignant lesions were likely to have an ultrasound correlate, especially when they presented as masses on MRI. However, the sonographic findings of these lesions were often subtle, and careful scanning technique was needed for successful MRI-ultrasound correlation.

Duodenal switch gastric bypass surgery for morbid obesity: imaging of postsurgical anatomy and postoperative gastrointestinal complications.

OBJECTIVE: The purpose of our study was to evaluate the normal postsurgical findings and appearance of gastrointestinal tract complications in patients who have undergone biliopancreatic diversion with duodenal switch bariatric surgery. We performed a 4-year retrospective review of 218 patients who underwent duodenal switch surgery. CONCLUSION: The most common complications of duodenal switch surgery were bowel obstruction, followed by ventral hernias and anastomotic leaks. Only 2% of cases required repeat surgery for management.

Expression of cytokeratin 20 in mucinous bronchioloalveolar carcinoma.

Mucinous bronchioloalveolar carcinomas (BACs) can closely mimic metastatic adenocarcinoma to the lung both clinically and morphologically. Several studies have demonstrated that the differential expression of cytokeratin 7 (CK7) and cytokeratin 20 (CK20) is a valuable diagnostic tool in differentiating primary pulmonary adenocarcinomas (PPAs) (usually CK7 positive/CK20 negative) from metastatic colonic adenocarcinoma (usually CK7 negative/CK20 positive). The present study is designed to correlate the histologic subtypes of PPA with expression of 7 and 20. A total of 113 cases of bonafide PPA were selected and classified according to the 1999 World Health Organization criteria as adenocarcinoma, NOS (n = 80), nonmucinous BAC (n = 14), and mucinous BAC (n = 19). Representive sections of all the tumors were immunohistochemically analyzed for CK7 and CK20 expression. To evaluate the diagnostic utility of CK7 and CK20 expression, 6 cases of colonic adenocarcinoma metastatic to the lung were tested with the same antibodies and compared with mucinous BAC. Results were expressed in a semiquantitative fashion based on the percentage of positive tumor cells: <10%, focal; 10% to 25%, 1+; 26% to 75%, 2+; > or =76%, 3+. All 113 PPAs exhibited strong, diffuse CK7 expression. With respect to CK20 expression, 17 of the 19 cases (89.4%) of mucinous BAC showed moderate to strong expression of this protein, whereas only 10 cases of conventional adenocarcinomas and 4 cases of nonmucinous BAC exhibited expression. All 6 examples of metastatic colonic adenocarcinomas were negative for CK7 and strongly positive for CK20. In summary, mucinous BAC is distinct from other PPAs by virtue of its CK20 expression. Although the CK7/CK20 immunoprofile is a valuable diagnostic marker for differentiating primary lung adenocarcinoma from metastatic colonic adenocarcinoma, caution should be exercised when dealing with mucinous BAC.