Biopsies of suspected lymphoma cases with history of pre-biopsy corticosteroid therapy present several diagnostic issues, such as the inability to demonstrate the neoplastic hematolymphoid cells, the similarity of post-corticosteroid changes with inflammatory demyelinating lesions, and the possibility of a demyelinating lesion preceding a central nervous system lymphoma. This report presents the case of a 51-year-old immunocompetent male with a solitary callosal mass, with immunomorphologic features suggestive of a demyelinating lesion on initial biopsy, and upon re-biopsy after three months revealed a diffuse large B-cell lymphoma. Awareness of these issues in post-corticosteroid stereotactic biopsy specimens, together with adequate clinical and radiologic data, is important for proper diagnosis and further therapeutic guidance.
Adrenal Cortex Hormones ; Demyelinating Diseases ; Lymphoma

This is a case of a 54-year-old, perimenopausal, Asian, woman, who presented with an enlarging left breast mass associated with whitish to bloody nipple discharge. A core needle biopsy, done in another institution, showed histologic findings of a mucinous carcinoma with triple negative “basal-like” biomarker status (ER, PR, HER2/neu). Six cycles of neoadjuvant chemotherapy were given after which the subsequent modified radical mastectomy revealed a centrally located, 10.0 cm, well-circumscribed, nodular, ovoid mass on gross examination. Microscopic findings showed tall columnar cells in stratification, tufts and papillary formations, with surrounding abundant extracellular mucin. The individual tumor cells exhibit enlarged, hyperchromatic, basally located nuclei with prominent nucleoli, abundant amphophilic and occasionally oncocytic cytoplasm which contains intracytoplasmic mucin. Based on the histologic features, “basal-like” biomarker expression, and additional immunohistochemical studies (positive CK7, negative CK20 and CDX2), this case demonstrates a pure mucinous cystadenocarcinoma of the breast. In addition to the rare histologic type, this case is exceptional since, despite multiple cycles of neoadjuvant chemotherapy, presence of extensive lymphovascular invasion and axillary lymph node involvement with extranodal extension remain evident.
Cystadenocarcinoma, Mucinous ; Breast Neoplasms