Showing papers in "Československá patologie in 2017"

Hybrid peripheral nerve sheath tumors: A review.

Abstract: Hybrid peripheral nerve sheath tumors (HPNST) are relatively recently described tumors. With ongoing research, a considerable amount of important findings have been made, much of which has substantial clinical implications. However, a comprehensive review of the whole topic has not been published in the literature so far. In the presented manuscript, the various hybrid tumors are discussed separately with a special emphasis on the morphological and immunohistochemical findings as well as on their association with tumor syndromes.

Hamartoma of mature cardiac myocytes. Autopsy case report

Abstract: Hamartoma of mature cardiac myocytes (HMCM) is a rare benign pseudoneoplastic myocardial lesion. We describe a case of 39-year-old Bulgarian woman living in the Czech Republic, who died because of rupture of anterior communicating artery aneurysm, and severe bronchopneumonia. An incidental finding at the autopsy was a whitish unencapsulated and not sharply demarcated tumor of the left ventricle and adjacent area of interventricular septum, which protruded above the plane of section. Microscopically the tumor consisted of various different forms of disorganized hypertrophic mature cardiac myocytes without vacuolization of cytoplasm, focally in a "herringbone" pattern. Dilated venules and thickened intramural coronary arteries, and intervening bands of connective tissue were present between cardiomyocytes in the tumor. Immunohistochemical staining of MIB1 for the detection of proliferative activity was completely negative. No inflammatory infiltration, adipose tissue or calcifications were present in the tumor.

Sebaceous adenoma arising in mature cystic teratoma of the ovary. Case report

Abstract: We report the case of a 44-year-old female with sebaceous adenoma arising in mature cystic teratoma of the ovary. The patient had a tumor in the left ovary; 125 x 90 x 70 mm. Microscopically, the tumor consisted of structures typical of dermoid cysts. However, large areas of sebaceous proliferation were found. These areas were comprised of sebaceous nodules with features similar to a sebaceous adenoma of the skin. Immunohistochemically, the tumor showed "wild-type" expression of p53 and low proliferative activity (Ki-67 index < 5%). To verify the possibility of Muir-Torre syndrome we performed immunohistochemical examination of DNA mismatch repair proteins expression. However, all four proteins examined (MSH2, MSH6, MLH1, PMS2) were positive. Sebaceous adenoma arising in mature teratoma of the ovary is rare. To the best of our knowledge, only six cases have been reported in the literature to date.

Myxoid tumors of soft tissues

Abstract: Myxoid tumours of soft tissue represent a heterogeneous spectrum of lesions with variable biological behaviour, from completely benign to highly aggressive malignancies. Myxoid tumours share abundant myxoid extracellular matrix, overlapping histopathologic features and immunohistochemical findings, with resulting diagnostic problems. This review article attempts to give the most complete list possible, with the characterization of gross and microscopic features, relevant immunohistochemical and molecular biology findings and to outline differential diagnosis.

[Molecular mechanisms of primary and secondary resistance, molecular-genetic features and characteristics of KIT/PDGFRA non-mutated GISTs].

Abstract: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. Most of them arise due to activating mutations in KIT (75 - 85 %) or PDGFRA (less than 10 %) genes. Identification of the activating mutations in KIT and PDGFRA genes, which code for receptor tyrosine kinases (RTKs), has improved the outcome of targeted therapy of metastatic, unresectable or recurrent GISTs. Primary and/or secondary resistance represents a significant problem in the targeted therapy by Imatinib mesylate (IM) in patients with GIST. An important mechanism of the secondary resistance is the evolvement of secondary mutations. Except for primary and secondary resistance, there is another problem of disease progression - a failure of tumor cells eradication even in the long term therapy of tyrosine kinase inhibitors. GISTs without mutations in KIT/PDGFRA genes constitute 10 - 15% GISTs in adults, and a majority (85 %) of pediatric GISTs. KIT/PDGFRA wild-type GISTs represent a heterogeneous group of tumors with several molecular-genetics and/or morphologic differences. KIT/PDGFRA wild-type GISTs are different in their molecular features, for example in mutations in the BRAF, KRAS, NF1 genes or defects of succinate dehydrogenase (SDH) subunits. KIT/PDGFRA wild-type GISTs are generally less sensitive to targeted therapy by tyrosine kinase inhibitors in comparison with KIT/PDGFRA mutated GISTs. Inhibitors of BRAF, PI3K (mTOR) or inhibitors of IGF1R and VEGFR receptors provide alternative therapeutic strategies.

[Molecular pathology of lung cancer in routine diagnostic practice: 2017 update]

Abstract: The group of non-small cell lung carcinomas includes tumors that are variable at the clinical, histopathological and molecular levels. Advances in the understanding of molecular pathology of lung adenocarcinomas in particular led to changes in their histopathological classification and treatment. Patients diagnosed with lung adenocarcinoma harboring specific mutations benefit from the administration of specific targeted therapy. Analysis of EGFR gene mutations and ALK rearrangement in lung adenocarcinomas are already routinely performed and are closely related to the indication for the administration of tyrosinkinase inhibitors. Besides EGFR mutations and ALK rearrangement there are also available other potential markers for analyzing, e.g. b-raf - BRAF, ROS1. Moreover, immunotherapy needs standardization of detection of crucial molecules, namely PD-L1. The aim of this review is to summarize the role of the most relevant molecules that could also serve as the therapeutic target for practicing pathologists.

[Update on the 2016 WHO classification of tumors of the central nervous system.Part 2: Embryonal tumors and other tumor groups (except for diffuse gliomas)].

Abstract: The 2016 revision of the WHO classification of tumors of the central nervous system is a conceptual advance over the 2007 classification system. Similarly to the group of diffuse gliomas, a significant shift in the understanding of the molecular background and tumor biology has recently occurred also in the category of embryonal CNS tumors, especially in medulloblastomas. The classification now incorporates new entities that are defined by both histology and molecular features. Updates in the group of gliomas (except for diffuse gliomas), in the meningeal tumors as well as in the tumors of peripheral nerve sheaths will also be discussed.

Mature teratoma of the uterine corpus: A case report.

Abstract: We report a case of a 37-year old female with a mature teratoma of the uterine corpus presented by metrorrhagia. Grossly, the tumor was polypoid without apparent invasion into the myometrium. Microscopically, the tumor consisted of disorganized mature neural tissue intermingled with nodular foci of cartilaginous tissue, groups of seromucionous glands and ciliated columnar respiratory epithelium. Fifteen months after the diagnosis, the patient showed no signs of tumor relapse. Then she was lost for a follow-up. Teratoma of the uterine corpus is rare; to the best of our knowledge only about 20 cases have been reported to date.