Extramedullary plasmacytoma of the breast is rare. It is important to recognize the imaging findings and include it as a differential consideration in multiple myeloma patients with a breast mass. A 74-year-old woman undergoing chemotherapy for relapsed multiple myeloma presented with a palpable mass in her right breast. A screening mammogram four months prior was unremarkable. She underwent a diagnostic right mammogram which showed two well-circumscribed hyperdense masses. An ultrasound of the right breast showed mixed echogenic masses with indistinct margins and increased vascularity. Ultrasound guided biopsy confirmed the presence of an extramedullary plasmacytoma. A follow-up whole body PET/CT demonstrated an FDG-avid right breast mass with extensive osseous metastases. CASE REPORTA 74-year-old woman undergoing chemotherapy for relapsing multiple myeloma (subtype IgG Lambda) presented to her medical oncologist with a new palpable right breast lump. A screening mammogram four months prior was interpreted as normal and given a BI-RADS Category 1 (negative) final assessment (Figure 1). Kappa free light chains were significantly decreased at 0.17 mg/dL (normal 0.33 -1.94 mg/dL) and Lambda free light chains were significantly elevated at 197 mg/dL (normal 0.57 -2.63 mg/dL). Clinically, the patient had persistent whole-body aches, oral bleeding, and bone pain. The patient was then referred to the breast imaging service for further work-up. She underwent a diagnostic right mammogram which showed two well-circumscribed hyperdense massesthere were no suspicious calcifications, nipple retraction, skin thickening, or areas of architectural distortion (Figure 2). A same-day ultrasound demonstrated two mixed echogenic masses with ill-defined margins and increased vascularity (Figure 3). Primary differential considerations included plasmacytoma and primary breast cancer. Hematoma was initially considered as the patient was on anticoagulation for deep venous thrombosis prophylaxis. However, given the presence of vascularity, it was deemed unlikely. An infectious etiology (i.e., breast abscess) was also considered given the rapid increase in size over four months. This was thought to be unlikely with no clinical signs of infection and central rather than peripheral vascularity. A microscopic examination of an ultrasound guided biopsy yielded plasma cell neoplasm (Figure 5). A follow-up PET/CT

The significance of background parenchymal enhancement (BPE) on screening and diagnostic breast MRI continues to be elucidated. Background parenchymal enhancement was initially deemed probably benign and followed or thought of as an artifact degrading the accuracy of breast cancer detection on breast MRI examinations. Subsequent research has focused on understanding the role of BPE regarding screening breast MRI. Today, there is growing evidence that a myriad of factors affect BPE, which in turn may influence patient outcomes. Additionally, BPE could represent an important risk factor for the future development of breast cancer. This article aims to describe the most up-to-date research on BPE as it relates to screening breast MRI in premenopausal women.

Purpose Medical errors result in significant mortality and morbidity. The purpose of this study is to analyze skull-base errors at a single tertiary institution, identify common anatomic sites of errors, and offer strategies to reduce errors in this region. Methods A Neuroradiology Quality Assurance Database of radiologic errors was searched for attending physician computer tomography and magnetic resonance imaging errors in skull-base pathology from 2014 to 2020. Data were limited to CT and MRI reports. Errors were separated into four subcategories (tumor, trauma, vascular, and congenital) and further divided by relevant anatomic site. Results A total of 90 skull-based errors were identified. Most errors were perceptual (87%), with common study types including MRI Brain (39%) and CT Head (24%). Most common errors were tumors (55%), followed by trauma (24%), vascular (10%), and congenital (7%). Six anatomic sites were identified and encompassed over half of errors (58%): sella, occipital bone, cerebellopontine angle/internal auditory canal (CPA/IAC), foramen magnum and clivus, cavernous sinus, and dural venous sinus. Summary Most of the skull-base errors were perceptual. Placing a strong emphasis on both the pathology and closely examining its critical anatomic site (sella, occipital bone, CPA/IAC, foramen magnum and clivus, cavernous sinus, and dural venous sinus) could potentially reduce up to 60% of errors in these regions.