Standardized pretreatment breast MRI--accuracy and influence on mastectomy decisions.

BACKGROUND AND OBJECTIVES: Routine pretreatment breast magnetic resonance imaging in newly diagnosed cancer patients remains controversial. We assess MRI accuracy and influence on mastectomy decisions after institution of standardized pretreatment MRI. METHODS: A prospectively collected database of 74 consecutive new invasive breast cancer patients with pretreatment breast MRI was reviewed for treatment choice, radiologic, and pathologic results. Thirty-eight of 72 patients with available surgical records underwent mastectomy. Mastectomy preoperative and operative electronic records were reviewed for treatment decision analysis. RESULTS: Seventeen of 72 (23.6%) invasive breast cancer patients were likely influenced to undergo mastectomy by new information from MRI. MRI reported that the multifocal/multicentric (MF/MC) rate was 20 of 72 (27.8%) versus 19 of 72 (26.4%) by surgical pathology. MRI sensitivity for MF/MC disease was 89.5% versus 11.8% for mammography. MRI specificity was 84.2%. All three false positives declined recommended preoperative biopsies. MRI MF/MC diagnosis highly correlated with pathology results, P < 0.001. CONCLUSIONS: Increased mastectomy rate from 29 to 52.8% after standardization of pre-treatment breast MRI for invasive cancer is largely due to MRI findings of increased extent of disease. These MRI findings correlate well with pathologic findings and appear to justify the performance of mastectomies in these patients.

Bone tumor mimics: avoiding misdiagnosis.

Whether discovered incidentally or as part of a focused diagnostic evaluation, the finding of a benign osseous lesion that has radiologic features resembling a bone tumor is not uncommon. Some of the more common benign and nonneoplastic entities that can sometimes be confused with tumors are the following: cortical desmoid, Brodie abscess, synovial herniation pit, pseudocyst, enostosis, intraosseous ganglion cyst, fibrous dysplasia, stress fracture, avulsion fracture (healing stage), bone infarct, myositis ossificans, brown tumor, and subchondral cyst. Accurate diagnosis and management of these lesions require a basic understanding of their epidemiology, clinical presentations, anatomic distributions, imaging features, differential considerations, and therapeutic options. This in-depth review of 13 potential bone tumor mimics will assist the radiologist in correctly identifying these benign lesions and in avoiding misdiagnosis and related morbidity. This review will also aid the radiologist in making appropriate recommendations to the referring physician for management or further imaging.

Controversies in breast MRI.

When used for appropriate indications, breast magnetic resonance imaging (MRI) is a powerful diagnostic tool. However, breast MRI has its share of controversies. These controversies can be a source of confusion for the radiologist or referring physician. This paper addresses 4 breast MRI controversies that we frequently encounter at our university hospital practice: (1) what are the appropriate indications for screening breast MRI? (2) what are the appropriate indications for the use of breast MRI as a problems-solving modality? (3) how does one interpret MRI imaging features that have substantial overlap between benign and malignant conditions? and (4) what are the appropriate indications for preoperative breast MRI? Illustrative case examples are provided.