The 48-year-old woman visited our hospital with a palpable mass on her right breast which has been increasing in size for the past two months. Physical examination revealed a hard and non-tender mass in the right breast. There were no signs of nipple retraction or skin thickening. Mammography demonstrated a large mass on the right breast with oval shape, circumscribed margin, and high density (Fig. 1a). On ultrasonography, the mass showed an oval shape, parallel orientation, circumscribed margin, heterogeneous echogenicity, and no posterior features (Fig. 1b). The fat-suppressed T2-weighted MR images showed an irregular circumscribed mass that was slightly hyperintense relative to parenchyma. On the contrast-enhanced MR imaging, a mass measuring 8.1 cm was observed in the right breast (Fig. 1c). It was an irregular shape and circumscribed margin with homogeneous enhancement. On dynamic imaging, the lesion displays fast contrast uptake in the early phase and rapid washout in the delayed phase consistent with type III kinetic curve (Fig. 1d). DW imaging (b=1000) showed reduced diffusion with corresponding mean apparent diffusion coefficient (ADC) value of 0.75 × 10^-3 mm²/s (Fig. 1e and f). MR spectroscopy showed a prominent Cho peak at 3.22 ppm, which was consistent with malignancy (Fig. 1g). The MR spectroscopy imaging was performed on a 3 tesla machine (Verio, Simens, Erlangen, Germany). Choline signal alterations associated with tumor were quantified using the 'normalized choline' signal approach. Using normalization, the choline signal can be calibrated to a relative and standardized value automatically. To perform this choline signal quantification, the choline signal in the tissue of interest is measured as is the choline signal generated by external reference probe. The specific imaging parameters were as follows: TR/TE 1500/100, number of excitations 128, sequence acquisition time 3 min 18 sec. Breast biopsy performed for histopathological identification of the mass was diagnostic for diffuse large B-cell lymphoma (CD 20+). Laboratory tests, PET/CT scan, CT of chest and abdomen, and bone marrow biopsy showed no involvement of other sites.

The 40-year-old woman presented with 3-week history of a painless left breast lump. On physical examination, a hard mass was palpated on the left breast. There were no other clinical symptoms such as nipple retraction, nipple discharge, or skin thickening. Mammography demonstrates a 4 cm mass on the left breast with oval shape, circumscribed margin, and equal density (Fig. 2a). Breast ultrasound showed an oval, parallel oriented mass with circumscribed margin at the 12 o'clock position of the left breast (Fig. 2b). It showed heterogeneous echogenicity with posterior enhancement. On the fat-suppressed T2-weighted MR images, the mass showed an irregular shape, circumscribed margin, and slightly hyperintense relative to parenchyma. The mass showed strong homogeneous internal enhancement after contrast material injection on MR imaging (Fig. 2c). On dynamic imaging, the lesion showed fast contrast uptake in the early phase and persistent enhancement in the delayed phase consistent with type I kinetic curve (Fig. 2d). DW imaging showed reduced diffusion with corresponding mean ADC value of 0.82 × 10^-3 mm²/s (Fig. 2e and f). High-amplitude Cho peak at 3.22 ppm is detected by single voxel MR spectroscopy (Fig. 2g). Ultrasound guided core needle biopsy performed on her breast mass and the histopathology showed diffuse large B-cell lymphoma after immunohistochemistry (CD 20+). Laboratory tests, PET/CT scan, CT of chest and abdomen, and bone marrow biopsy showed no involvement of other sites. The patient was treated with chemotherapy.