[ALK-positive anaplastic large cell lymphoma of paranasal sinuses: two cases report and literature review]. / ALK-pozitivnaya anaplasticheskaya krupnokletochnaya limfoma s porazheniem pridatochnykh pazukh nosa: dva klinicheskikh nablyudeniya i obzor literatury.

ALK-positive anaplastic large cell lymphoma is a rare T-cell lymphoma with ALK gene rearrangement that develops in children and young adults. The disease almost always affects the lymph nodes, and extranodal areas are also frequently involved. This article describes two cases of atypical localization of ALK-positive anaplastic large cell lymphoma with involvement of the paranasal sinuses.

[Clinical case - neoplasm of the nasal septum, which turned out to be papillary cancer of the ectopic thyroid gland]. / Klinicheskii sluchai ­ novoobrazovanie peregorodki nosa, okazavsheesya papillyarnym rakom ektopirovannoi shchitovidnoi zhelezy.

In this clinical case, papillary carcinoma was detected in the ectopic area of the thyroid gland in the presence of an unchanged thyroid gland of natural localization. An extremely rare disease is presented and an examination algorithm is proposed that is recommended to exclude unusual pathology in the absence of a response to ongoing conservative treatment.

[Use of crizotinib for refractory ALK-positive lymphomas]. / Primenenie krizotiniba pri refrakternykh formakh ALK- pozitivnykh limfom.

AIM: To evaluate the safety and efficacy of crizotinib used in pediatric patients with relapsed or refractory ALK-positive anaplastic large-cell lymphoma (ALCL). SUBJECTS AND METHODS: The paper describes the experience with crizotinib used in 8 patients with refractory ALK-ALCL before and after allogeneic hematopoietic stem cell transplantation (HSCT). RESULTS: All the 8 (100%) patients treated with crizotinib were recorded to have complete responses, including complete metabolic ones (tumor disappearance as evidenced by positron emission tomography (PET)/computed tomography. CONCLUSION: Low and manageable toxicity of crizotinib and complete PET-negative responses in patients with resistant ALK lymphomas favor the need to test the drug as first-line therapy, by possibly decreasing the intensification of chemotherapy.

[Extrarenal rhabdoid tumor: A review of literature and a report of cases with atypical morphology]. / Ékstrarenal'naia rabdoidnaia opukhol'. Obzor literatury i opisanie sluchaev s netipichnoi morfologiei.

Extrarenal extracranial rhabdoid tumor (EERT) is a rare malignant pediatric tumor characterized by extremely aggressive behavior, rapid metastatic spread, low survival rates, and no targeted therapy. The morphological diagnosis of classical cases of EERT is not difficult and it is based on its characteristic histologic pattern and immunohistochemical findings in a relatively short time, which allows one to immediately initiate therapy. The paper describes two cases of ERRT in the complete absence of classical rhabdoid morphology, as revealed by light microscopy when the material was primarily assessed. The final diagnostic search could establish a diagnosis of EERT in both cases on the basis of immunohistochemical findings.

[Primary thyroid extranodal marginal zone lymphoma].

The paper gives the data available in the literature on the clinical and morphological features of thyroid lymphomas and on their diagnostic principles. The authors' observation details the histological and immunohistochemical characteristics of primary thyroid extranodal marginal zone lymphoma. The specific feature of the observation is total thyroid tissue substitution for tumor cells so the characteristic sign of chronic autoimmune thyroiditis were undetectable, but found only immunohistochemically from the remaining thyroid tissue follicle-like structures, which bears out the relationship between the development of lymphoma and autoimmune thyroiditis.

[Atypical teratoid/rhabdoid tumors of childhood].

The paper describes 6 cases of atypical teratoid/rhabdoid tumors (ATRT) in the complete absence of classical rhabdoid elements isolated from 25 INI1-negative central nervous system tumors investigated in the period 2006 to the present time. Analysis of the specific features of the histological structure of INI1-negative tumors could identify a few histological types of ATRT according to the conventionally standardized criteria for diagnostic search.