Bilateral primary breast diffuse large B-cell lymphoma detected by mammography but partially occult on FDG PET/CT: A case report.

A 52-year-old female presented with complaints of a painful left breast mass. On examination, a tender mass was noted in the left breast. Bilateral diagnostic mammography revealed an irregular, dense mass with indistinct borders in the left breast. A similar but smaller dense mass was also identified in the right breast. Ultrasound examination confirmed a heterogeneous, hypoechoic, irregular, microlobulated, antiparallel mass in the left breast. A smaller mass with similar characteristics was also observed in the right breast. Histopathology of both breast masses revealed bilateral diffuse large B-cell lymphoma. PET/CT demonstrated abnormally increased metabolic activity only in the larger left breast mass, while the contralateral mass was not metabolically avid. The patient received 6 cycles of R-CHOP chemotherapy. A follow-up mammography study performed 1 year after the initial diagnosis showed complete resolution of the breast masses bilaterally across all imaging modalities.