Uncommon breast tumors. A report of four cases

Abstract

Breast cancer is the most common malignancy and the second leading cause of cancer mortality in women, forcing the determination of an early and accurate diagnosis. There are also other uncommon neoplastic lesions. On account that many of them have different prognosis and treatment, it is important to differentiate them. The objective of this work is to interpret the morphology of 4 cases of exceptional presentation, in order to consider them in medical practice.

Case 1: 30yo woman, tumor in right upper-outer quadrant. Biopsy: compatible with signet-ring cell carcinoma. In 6mo it grew considerably and a simple mastectomy was performed. We observed a whitish and ulcerated tumor of 24x22x8 cm. Microscopy: mesenchymal neoplasm, marked anisokaryosis, vacuolated cytoplasm, bizarre nuclei, increased mitoses, necrosis, and ulcerated skin. Triple-negative, Ki-67 30%. Diagnosis: Primary pleomorphic liposarcoma.

Case 2: 63yo woman with a left painless multinodular mass. Simple mastectomy. Intraoperative biopsy: myxoid spindle cell lesion. Macroscopy: 25 cm tumor, lobulated and pseudoencapsulated. Cut surface is solid, grayish, with mucinous areas and necrohemorrhagic foci. Microscopy: spindle cells, clear cytoplasms, small, hyperchromatic nuclei, inconspicuous nucleoli, nuclear pseudoinclusions, myxoid background, collagenous areas, scarce mitoses. CD34(+), ASMA(+), Ki-67 15%. Diagnosis: Breast myofibroblastoma.

Case 3: 82yo woman with a verruciform mass on the skin of the right breast. Macroscopy: 1.4x1x0.9 cm lesion, reddish brown, well-defined borders. At the surgical limit, another elevated lesion is observed, 1.3x9x0.5 cm, whitish, ulcerated. Microscopy: dermis with atypical neoplastic endothelial cells, forming dilated vessels and papillae, Others are spindle-shaped and epithelioid. Diagnosis: High grade angiosarcoma.

Case 4: 42yo woman, right painless palpable mass. Quadrantectomy. Macroscopy: 0.6 cm multilobulated, irregular, whitish lesion with central cystification. Microscopy: lobular tubulo-epithelial structures surrounded by basal and interstitial myoepithelial cells with clear, polygonal, and fused cytoplasm. p63(+), Actin(+), Vimentin(+), low Ki-67. Diagnosis: lobulated adenomyoepithelioma

Uncommon cases of neoplasms require specific morphological criteria and resolution with immunohistochemical techniques in most cases. Diagnoses must be confirmed with histopathological study and eventually with immunohytochemistry.