Vol 4, No 3-4 (2021)

Chordoma is a rare mesenchimal tumor with anusual clinical behavior and morphologic appearance. In the current study we examined 94 cases of chordoma, predominantly localized in sacrum, ages 3-72, 44 men and 50 women. Six cases of dedifferentiated variant of chordoma were revealed. In an effort to clarify the diagnosis and differentiation, the tumor samples of chordoma were examined by immunohistochemistry with a panel of antibodies. The panel included antibodies to cytokeratin, epithelial membrane antigen (ЕМА), D2-40, GFAP (glial fibrillary acidic protein), S-100, brachyury, chromogranin A, TTF-1 (thyroid transcription factor), PSA, CDX-2, mammaglobin. The diagnosis of one case of poorly differentiated chordoma was proved by the lack of SMARCB1/INI-1 reactivity. A negative reaction with chromogranin A, D2-40, as well as a reaction with organ-specific proteins (TTF-1, mammaglobin, PSA, CDX-2) made it possible to exclude chordoma and reveal cancer metastases of various localization. Several examples of benign notochordal rests and differential with classic chordoma are proposed in the paper.

In this article, we discuss main aspects of differential diagnosis between periductal stromal tumor of the breast and other variants of fibroepithelial breast tumors on the example of one case.

Primary breast sarcomas (except malignant phylloid tumors) are exceedingly rare tumors that account for less than 0.1 % of all malignant breast tumors. Approximately 25 % of all primary breast sarcomas are angiosarcomas. In this article, we report two cases of primary angiosarcoma and discuss challenges of its differential diagnosis.