Predominance Of Single Cells Research Articles

Regularities of structural organisation of the heart myxomas in patients with Karney complex

Myxomas of the heart are one of the most common primary heart tumours, which most often develop in the left atrium, are characterised by a benign nature and no relapses after surgical removal of the tumour. Karney complex is an autosomal dominant disease characterised by numerous tumours, in particular, myxomas of the heart. Insufficient coverage of this pathology in the literature leads to an erroneous diagnosis, progression of the disease and inadequate treatment. The purpose of the study was to determine the morphological features of heart myxomas in patients with Karney complex. Using light microscopy, a morphological examination of the heart myxomas was performed, which were removed during 7 operations. Histological sections were made from the operating material, which were stained with hematoxylin and eosin, according to Van Gieson, fuchselin, and Masson's Trichrome Stain in the Zerbino-Lukasevich modification. A comparison of the group of heart myxomas of patients with the Karney complex (16 tumours) with a group with myxomas of the heart that occur sporadically (278 tumours) was made to identify morphological features. It was established that myxomas of the heart are multiple, they were detected with the same frequency in the right and left chambers of the heart. It was generalised that in myxomas of the heart, signs of both alteration and high proliferative activity of endotheliocytes and fibrous connective tissue cells are noted. Secondary myxomas of the heart in patients with the Karney complex have the same structural organisation as primary tumours, but most often they are not relapses, more often they are multiple and do not have a predominant localisation in the left atrium. The analysis established an identical cellular composition of both groups of heart myxomas, which suggests the same source of tumour growth, but the presence of more complex cell formations in sporadic myxomas and the predominance of single cells in Karney heart myxomas indicate the existence of differences in their morphogenesis

Cytomorphologic features of SMARCA4-deficient non-small cell lung carcinoma and correlation with immunohistochemical and molecular features.

SMARCA4/BRG1-deficient tumors and those that have loss of SMARCA/BRG1 have been described as various aggressive carcinomas and sarcomas, including a subset of non-small cell lung carcinoma (NSCLC). Cytomorphologic features of NSCLCs are yet to be described. The objective of this study was to evaluate the cytomorphologic features, immunohistochemical profile, and molecular profile of SMARCA4/BRG1-deficient NSCLC (SMARCA4-dNSCLC). The authors retrospectively searched for cases with SMARCA4/BRG1 functional loss alterations, which were identified in molecular studies and further confirmed by immunocytochemistry, and they reviewed the cytomorphologic features. Tumors with BRG1 loss were also stained with an extensive antibody panel. Molecular profiling and clinical information of the identified cases were scrutinized. In total, 12 cytopathology cases from different anatomic sites were included. All cases showed variable expression of cytokeratin irrespective of type. One-half of cases had glandular features, followed by squamoid features, and poorly differentiated features. The most common cytologic features included sheets or papillary architecture, round or oval cell shapes, nuclear enlargement, moderate-to-marked pleomorphism, and coarse chromatin. Two cases with poorly differentiated cytomorphology had a predominance of single cells, scant cytoplasm, and macronucleoli. Variable expression of epithelial markers was noted in all cases. TP53 was the most frequently co-mutated gene in SMARCA4-dNSLCs. This study demonstrates that SMARCA4-dNSCLCs can have a wide spectrum of cytomorphologic features, ranging from a relatively well differentiated adenocarcinoma to a poorly differentiated/undifferentiated carcinoma, with the majority of cases exhibiting some high-grade features, such as mitosis, apoptosis, necrosis, and marked pleomorphism.

Subungual Melanoma

Subungual melanoma (SUM) is an uncommon variant of melanoma that is often difficult to diagnose, both clinically and pathologically. In an attempt to provide pathologic clues to diagnosis, especially in early lesions or small biopsies, and to provide practical advice to pathologists in reporting, the clinicopathologic features of 124 cases of SUM were reviewed, the largest series reported to date. The features of 28 cases of subungual melanoma in situ (MIS), comprising 4 cases of MIS and 24 cases where areas of MIS were present adjacent to dermal-invasive SUMs, were compared with those of a similar number of acral nevi to identify useful distinguishing features. The median age of the patients was 59 years and the most common site was the great toe (24%). Nine percent of cases were AJCC stage 0, 14% were stage I, 41% were stage II, 32% were stage III, and 4% were stage IV at initial diagnosis. The commonest histogenetic subtype was acral lentiginous (66%), followed by nodular (25%) and desmoplastic (7%). The majority of tumors were locally advanced at presentation with 79% being Clark level IV or V. The median Breslow thickness was 3.2 mm. The median mitotic rate was 3 per mm and 33% of cases demonstrated primary tumor ulceration. Seven of 29 patients (24%) who underwent a sentinel lymph node biopsy had nodal disease. Multivariate Cox-regression analysis showed higher disease stage to be the only significant predictor of shortened survival. In comparison to acral nevi, MIS more frequently showed lack of circumscription, a prominent lentiginous growth pattern, predominance of single cells over nests, moderate-to-severe cytologic atypia, a dense and haphazard pagetoid intraepidermal spread of melanocytes, and the presence of junctional/subjunctional lymphocytes ("tumor infiltrating lymphocytes"). Tumor infiltrating lymphocytes have not been highlighted previously as a feature of subungual MIS and represent a useful diagnostic clue. Guidelines for the reporting of SUMs are also presented. Knowledge and recognition of the pathologic features of SUMs and the important features that distinguish them from nevi should reduce the frequency of misdiagnosis.