Extramedullary Plasmacytoma of the breast in a patient with Multiple Myeloma

Abstract

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

Radiologic-Pathologic Review of Non-Epithelial Malignancies and Metastases in the Breast: A Pictorial Essay

“…Variable T1 and T2 signal intensities have been reported, including low-to-isointense signal on T1-weighted images and intermediate-to-high signal on T2-weighted images (Figure 8 24 ). 25,27 Restricted diffusion and homogenous enhancement with delayed washout kinetics have also been noted (Figure 8 24 ). [25][26][27] A limited number of studies have reported on 18 F-FDG PET/CT findings in breast plasmacytoma.…”

“…25,27 Restricted diffusion and homogenous enhancement with delayed washout kinetics have also been noted (Figure 8 24 ). [25][26][27] A limited number of studies have reported on 18 F-FDG PET/CT findings in breast plasmacytoma. [26][27][28][29] Majority of these cases showed 18 F-FDG avidity, 26,27,29 although low-grade uptake has also been reported.…”

Multiple myeloma extramedullary lesions presenting withmultiple soft tissue masses in the neck, chest, abdomen, and back: a case report

“…Extramedullary soft tissue masses have been reported in the gingiva, liver, pituitary gland, small intestine, breast, thyroid cartilage, heart, testis, stomach, and soft tissue of the neck [5][6][7][8][9][10][11][12][13] . Soft-tissue involvement is associated with signi cantly shorter progression-free survival and overall survival, with a median survival of 8.5 months [14] .…”

Solitary Plasmacytoma of the Breast: A Case of an Uncommon Breast Neoplasm

“…According to the literature, BP accounted for roughly 1.5% of all plasmacytomas; of which, only 15% of these instances were classified as primary BP. The remaining 85% of cases were secondary to MM [ 6 , 11 ]. Through this case, we hope to provide insight into the diagnosis, treatment, and prognosis of this rare and intriguing type of cancer.…”

“…It is important to note that extramedullary plasmacytomas (EP) are often seen in patients with MM; however, these lesions are not necessarily solitary and widespread. Te symptoms associated with widespread proliferation of abnormal plasma cells are often greater, compared to symptoms seen due to a single lesion [1][2][3][4][5][6][7].…”