[Microglandular adenosis of the breast].

The presented case describes the difficulties of diagnosis of the breast microglandular adenosis (MGA), taken by clinicians for a malignant process due to the nature of growth and large size. Criteria for histological and immunohistochemical diagnosis and differentiation of MGA with malignant neoplasms, in particular, with tubular breast carcinoma, are presented. Taking into account the rarity of the pathology and the absence of described cases in the Russian-language literature, the observation is of interest to pathologists and clinicians.

[Metastatic lesion of the bone marrow caused by primary angiosarcoma of the spleen].

The article presents a rare case of bone marrow metastasis of the spleen angiosarcoma. The observation is of particular interest due to the fact that secondary bone marrow damage in angiosarcoma in the vast majority of cases is due by primary tumor growth in the spleen. Clinically, such cases may resemble the course of blood diseases with hematological disorders and splenomegaly.

[Rare kidney tumor - thyroid-like follicular carcinoma].

The literature review provides an analysis of a rare malignant tumor of the kidney: thyroid-like follicular carcinoma of the kidney (TLFCK). In morphology, this tumor is extremely similar to thyroid follicular carcinoma, but the immunophenotype of tumor cells is different. TLFCK has an indolent clinical course, rarely metastasizes, and even the development of metastases does not mean an unfavorable prognosis for the patient.

[Thyroid-like follicular carcinoma of the kidney].

Thyroid-like follicular carcinoma of the kidney (TLFCK) is an extremely rare histological variant of renal cell carcinoma, not yet included in the WHO list of tumors. This tumor has a characteristic morphological structure strikingly resembling follicular carcinoma of the thyroid gland, but differing from itby the immunophenotype of tumor cells. TLFCK is characterized by an indolent clinical course, rarely metastases, and even the presence of metastases does not lead to a worsening of the prognosis for the patient.