[Analysis of the work of the Immunohistochemical Quality Control Center of the Russian Medical Academy of Continuous Professional Education of the Ministry of Health of Russia in 2023]. / Analiz raboty Tsentra kontrolya kachestva immunogistokhimicheskikh issledovanii FGBOU DPO «RMANPO¼ Minzdrava Rossii v 2023 godu.

The article demonstrates a detailed analysis of the results of the rounds of quality control of immunohistochemical studies conducted by the Central Committee of the Immunohistochemical Quality Control Center of the Russian Medical Academy of Continuous Professional Education of the Ministry of Health of Russia in 2023. Typical shortcomings and errors in the immunohistochemical examination of various tumors have been identified and ways to eliminate them are given. Particular attention is paid to defining a panel of standard breast cancer markers and eliminating the shortcomings of immunohistochemical examination of markers of accompanying diagnosis.

[Experience of local radiation therapy and total irradiation of the skin by electron beam in patients with primary B and T-cell lymphomas of the skin].

The problem of the treatment of primary malignant lymphomas of the skin is now becoming increasingly important due to the increase of cases among people of working age and disability of these patients. In most cases lymphomas of the skin have a T-cell origin, the most common of skin lymphoma is mycosis fungoides. It is poorly studied the role of electronic radiation therapy in local and systemic skin lymphomas as well as methodological questions of its application, so research in this field is actual. Therefore the aim of the study is improving of the efficiency of therapy in patients affected by non-Hodgkin's lymphoma with skin lesions by the use of local radiation therapy and total skin irradiation by electron beam.

[10 years of testing of the HER2 status in breast cancer in Russia].

The paper analyzes 10 years' experience in HER2 status testing in breast cancer in Russia. The ASCO/CAP HER2 testing guidelines adaptable to the work of pathologists in Russia are considered.

[The first experience of external quality control of immunohistochemical studies in the diagnosis of lymphoproliferative diseases].

The paper presents the results of estimating the quality of immunohistochemical (IHC) staining in 36 pathologic laboratories of the Russian Federation. The results of IHC stains were assessed in 17 markers (CD3, CD5, CDIO, CD15, CD20, CD23, CD30, Bcl2, Bcl6, Pax5, TdT, Mum1, Cyclin D1, Ki-67, Kappa, Lambda, ALK), which are frequently used in the diagnosis of lymphoproliferative diseases, in the sections of specially formed tissue matrices. The study conducted in most participating laboratories has revealed the considerable IHC staining technology flaws that can critically affect the quality of diagnosis of lymphoproliferative diseases; the diagnostic capacities of some participating laboratories are inconsistent with the solved problems for a number of key antibodies being unavailable.

[The diffuse type of giant cell tumors of the tendon sheaths].

The authors give a morphological and immunohistochemical description of diffuse giant cell tumors of the tendon sheath, which differ in the composition of neoplastic cells. Immunohistological detection of CD68, HAM56, CD45, and lysozyme is of crucial importance in the differential diagnosis with malignant soft tissue tumors. Attention is drawn to the high proliferative activity of tumor cells; the Ki-67 index is as high as 40% in occasional portions, which may give a misimpression of malignancy.

[The place of dendritic cells in the microenviroment in Hodgkin's lymphoma].

Dendritic cells (DCs) are the least studied microenvironment elements in Hodgkin's lymphoma (HL). Ninety-five lymph nodes were morphologically and immunohistochemically studied in patients with classical HL. The authors found CDla- and langerin-positive DCs in the presence of T lymphocytes, which were localized in the close proximity to neoplastic Reed-Sternberg cells (RSCs). There were also CD23-positive follicular DCs, which were typically located at the periphery of tumor foci, in the areas of residual follicular structures, were surrounded by B lymphocytes and were rarely associated with RSCs. There were two morphologically distinct groups among the CD 1a- and langerin-positive DCs; one had developed cytoplasmic processes, which formed a network around the RSCs (probably a more mature/functionally active form); the other had round cells with short cytoplasmic processes, loosely distributed around the neoplastic cells (a less mature/active form). The function and role of CD1a- and langerin-positive DCs in HL call for further investigation. The topographic closeness of these DCs to RSCs suggests that these cells play a considerable role in the pathogenesis of HL.

[Combined therapy and radiotherapy in stage-II Hodgkin disease].

The aim of the study was to raise efficacy of combined treatment of stage II Hodgkin's disease by optimization of fractionation and volume of irradiation. It included 179 patients with involvement of supradiaphragmatic lymph nodes treated in 1986-2006. It was found that multi-fractionation was followed by lower frequency of relapse as compared with standard regimens as well as rates of early ones. The most efficient dosage was 30-36 Gy as far as frequency, term of relapse occurrence and recurrence-free survival were concerned.

[Morphological diagnosis of myeloid sarcomas].

Myeloid sarcoma (MS) is an extramedullary tumor made up by myeloid blasts that may be undifferentiated or show varying degrees of maturation. This paper gives the results of morphological and immunohistochemical studies of 15 cases of MS. The patients' age was 32.7 +/- 14.3 years. The most involvement was observed in lymph nodes (6 cases) and vertebral bodies with spread to the epidural space and soft tissues (3 cases). Differentiated MS was diagnosed in 60% of cases. The immunohistochemical profile of MS was characterized by the expression of MPO (100%), CD68 (92.8%), CD34 (77%), CD 117 (53.8%), lysozyme (50%), and TdT (44.4%). The blast structure similarity of myeloid blasts and other cells to chromatin makes MS difficult to diagnose. Without immunohistochemical study, MS is misdiagnosed and most frequently misinterpreted as one of the types of non-Hodgkin's lymphoma.

[Monophasic angiomyolipoma (PEComa) of the liver].

The paper provides a morphological and immunohistochemical description of hepatic angiomyolipoma in a 29-year-old woman. Microscopically, it is a tumor with trabecular and diffuse growth patterns, which consists of polygonal cells with pleomorphic nuclei and extensive cytoplasm accumulated around the nucleus. Immunohistochemical study is of crucial importance in making the diagnosis. The tumor cells coexpress smooth muscle actin and the melanin markers: HMB-45, melan A, and MITF. The proliferative activity of the tumor is very low (Ki-67 index < 1%). According to the present views, angiomyolipoma belongs to perivascular epithelioid cell tumors (PEComas).

[Role of modified radiotherapy in the combined treatment of orbital non-Hodgkin lymphoma].

The study included 36 patents (primary tumor--27, recurrent orbital lymphoma--9) with diagnosed non-Hodgkin's orbital or conjuctival lymphoma treated at the Center's Clinic (1999-2007). All patients received an average multifractionated dose of 34.5 Gy from the S1-75-5 linear electron accelerators (Philips) generating 6 MeV of braking radiation. Also, the Elekta Precise with a multi-lobe collimator (6 and 18 MeV of braking and 4-20 MeV of electron radiation) was used. Relevant radiotherapy was given to 3 patients while conventional one--to the rest of the group: CHOP chemoradiotherapy--24, R-CHOP--3. Complete local response was reported in all patients (100%). Early-onset radiation-related complications presented mainly as conjunctivitis (22). Late-onset ones were cataract and dry eye (5) (13.9%).

[The significance of immunohistochemistry in the investigation of liver neoplasms: differential diagnosis, prognostic markers].

The immunohistochemical investigation used 55 primary hepatic tumors (hepatocellular carcinoma (HCC)--32, cholangiocellular carcinoma (CCC)--23). Wide panels of such antibodies as hepatocytic marker (Hep Par--1) CK-8, CK-19, polyclonal CEA, CD10, alpha-fetoprotein, TTF-1 as well as proliferative features of HCC (Ki-67) including regulators of stage-to-stage transition through mitoses of tumor cells (cyclin-D1 and A, genes p53 and RB), unrestricted tumor cell mitosis (telomerases), and intercellular adhesion marker (beta-catenin) were employed for differential diagnosis of neoplasia. The most efficient marker HCC was Hep Par--l (sensitivity--100%, specificity--92%) while the sensitivity of CCC (CK-19) was 83% and specificity--78%. Of particular importance for differentiation between HCC and CCC were the nature of microcirculatory flow identifiable with the aid of CD31 and presence of pseudocapsule in HCC detected by means of calponin. CEA and CD10 played a part too while the remaining markers were either expressed very seldom (alpha-fetoprotein) or absent (TTF-1). Most nuclear antigens (Ki-67, cyclin-A, p53 and RB) were intensely expressed in poorly-differentiated HCC cells. Cyclin-D1 and mutated suppressor-gene p53 expression involved lowered overall and relapse-free survival.

[Current views of the histogenesis and pathogenesis of Hodgkin lymphoma].

The diagnosis of Hodgkin lymphoma is based on the identification of Beresovsky-Reed-Sternberg (B-R-S) cells which are surrounded by inflammatory cells. The tumor cells are of B-cell origin and their mutations are sometimes observed. T-cell immunophenotype is recorded in 5% of the observations. Epstein-Barr virus is found in one third of the patients.

[Solitary orbital fibrous tumor in a 12-year-old child].

Solitary orbital fibrous tumor was diagnosed in a 12-year old boy admitted to hospital for right-sided exophthalmos. MRI revealed orbital mass and surgical resection was performed. Histologically the tumor was composed of round or spindle cells with a lot of multinucleate giant cells and pseudovascular spaces. The neoplasm was regarded as a mixoid type of a solitary giant cell-rich fibrous tumor. Immunohistochemical analysis revealed coexpression of CD34, CD99, bcl-2, and CD99 (mic-2). The most important clinical, morphological, and immunohistochemical manifestations are presented in the paper. Major criteria for the differential diagnosis of solitary orbital fibrous tumor and the similar soft tissue tumors are discussed.

[Solitary fibrous tumor: a clinico-morphological and immunohistochemical study].

Solitary fibrous tumor is a rare neoplasm which may occur at any site although it is more frequent in the pleura, mediastinum and lung. The study used 4 cases of tumor localization in the pleura and orbit. Three cases presented as a "hemangiopericytic" variety of spindle cells; there were numerous giant cells in orbit tumor. Solitary fibrous tumor revealed enhanced expression of vimentin, CD34, bel-2 and CD99. Expression of S-100, desmine and non-striated muscle actin was found in few cells in some cases. Such features as large size (over 10 cm), necrosis, high cellularity, nuclear polymorphism and high mitotic index (more than 4 mitoses within 4 visual fields, at high magnification) were used as malignancy criteria:. Tumor histological pattern of "hemangiopericytic" variety could be reliably identified thanks to immunohistochemical procedure.

[Morphological and immunohistochemical characteristics of blastic NK-cell lymphoma].

This is a review characterizing a rare skin tumor which in the WHO-EORTC classification of skin lymphoma is called CD4+/CD5+ hematodermal tumor (blastic NK-cellular lymphoma). Analysis of clinical picture and results of histological investigation of tumor nodules in the skin and bone marrow does not allow one to reveal specific signs sufficient for diagnosis. Immunohistochemical study with panel of markers including CD4, CD56, CD68, TdT is necessary for this tumor diagnosis.

[Achievements in morphological diagnosis of prostatic cancer: alpha-methylacyl-coenzyme-A-racemase--a new marker of malignant cell transformation].

Gene P504S is considered as the most specific for prostatic carcinoma and its protein (alpha-methylacyl coenzyme A racemaze (AMACR/P504S) is higly sensitive and specific marker not only for adenocarcinoma cells but also for preceding changes - prostatic intraepithelial neoplasm (PIN). AMACR/P504S seems to be the first marker of malignant transformation and tumor progression. Use of immunohistochemical method for revealing this marker together with methods of basal prostatic cells observation (cytokeratin of a high molecular weight, cytokeratin 5/6, p63) improves morphological diagnosis of prostatic carcinoma, particularly on the material of needle biopsies. This combination allows one to identify neoplastic nature of some difficult lesions.

[T-cell panniculitis-like lymphoma of the subcutaneous fat: clinicomorphological and immunohistochemical analysis].

3 cases of T-cell panniculitis-like lymphoma of the subcutaneous fat are reported. Clinical, histological and immunohistochemical findings are presented. Histologically, we found lobular structure, atypical small and middle-size lymphoid cells, angiocentric growth, erythrophagocytosis. Immunohistochemically it was a cytotoxic phenotype of atypical T-cells. T-cell panniculitis-like lymphoma is a special variant of non-Hodgkin's lymphoma which is diagnosed immunohistochemically.

[Clinical and molecular correlation between chronic hepatitis and hepatocellular carcinoma induced by hepatitis B virus].

The role of X-gene of hepatitis B virus (HBV), telomerase gene, structural HBV proteins is considered. Both factors of the virus and those of the host are involved in hepatocarcinogenesis. The duration of chronic B hepatitis may influence mitogenic and mutagenic conditions for accumulation of occasional genetic and chromosomal damage and result in hepatocarcinoma development.