👤 Makuša Michal

The Rare Gynecologic Sarcoma study involved 23 institutions from 10 countries focusing on myxoid leiomyosarcoma and non-smooth muscle uterine sarcomas. Here, we present the main results of the study, including the comparison between the original and final diagnosis, the frequency and type of molecular aberrations, and the clinicopathologic outcomes. A total of 379 cases were included, with available results for next-generation sequencing (NGS) RNA in 338 of 379 cases and NGS DNA in 335 of 379 cases. According to the original diagnoses, the study included 204 cases of low-grade endometrial stromal sarcoma (LG-ESS), 75 cases of high-grade endometrial stromal sarcoma (HG-ESS), 74 cases of undifferentiated uterine sarcoma (UUS), 17 cases of myxoid leiomyosarcoma, and 9 cases of unclassifiable sarcoma. The results of our second reading showed that 29% (110/379) of all the tumors had been originally misdiagnosed. After the reclassification, the final diagnoses were 147 cases of LG-ESS, 69 cases of HG-ESS, 58 cases of UUS, 3 cases of LG-ESS with high-grade transformation, 7 cases of perivascular epithelioid cell tumor, 9 cases of uterine tumor resembling ovarian sex cord tumor, 8 cases of tumors with a KAT6B/A::KANSL1 fusion, 2 cases of tumors with an NTRK fusion, 29 cases of undifferentiated carcinoma, and 47 tumors with smooth muscle differentiation. The molecular testing showed that LG-ESS harbor a recurrent fusion in 75.9% and HG-ESS in 43.7% of cases. The results of our study emphasize the diagnostic, prognostic, and predictive significance of molecular testing in mesenchymal uterine tumors. Show less

Uterine sarcomas with KAT6B/A::KANSL1 fusion represent a new entity characterized by bland morphology, commonly with hybrid features of low-grade endometrial stromal sarcoma (LG-ESS) and tumors with smooth muscle differentiation. In our study, we performed a detailed morphological, immunohistochemical, and molecular analysis of 9 cases of these tumors. Six of those had been originally diagnosed as LG-ESS, one as leiomyoma, one as leiomyosarcoma, and the remaining case as sarcoma with the KAT6B/A::KANSL1 fusion. Seven cases showed overlapping features between endometrial stromal and smooth muscle tumors, one case resembled cellular leiomyoma, and one case resembled high-grade endometrial stromal sarcoma. Immunohistochemically, the tumors showed a common expression of smooth muscle markers and endometrial stromal markers. Molecular findings showed the KAT6B/A::KANSL1 fusion in all cases (by NGS and FISH). In addition, mutations affecting genes such as TP53, PDGFRB, NF1, RB1, PTEN, ATM, RB1, FANCD2, and TSC1 were present in all 5 cases with aggressive behavior. One patient with no evidence of disease showed no additional mutations, while another harbored a mutation of a single gene (ERCC3). Of the 8 patients with available follow-up, two died of disease, 3 are currently alive with disease, and 3 have no evidence of disease. The correct recognition of tumors with the KAT6B/A::KANSL1 fusion is essential because despite the bland morphological features of most cases, these tumors have a propensity for aggressive behavior. Show less

Carcinoma ex pleomorphic adenoma (CXPA) is an aggressive epithelial and/or myoepithelial neoplasm that arises in association with a pleomorphic adenoma (PA). Its etiopathogenesis remains poorly understood, but it is believed that the development of this tumor is due to the accumulation of genetic, protein, metabolic, and epigenetic alterations in a PA. A retrospective review of the Salivary Gland Tumor Registry in Pilsen yielded 84 CXPA, namely 25/84 salivary duct carcinoma (SDC), 15/84 myoepithelial carcinoma (MC), 1/84 epithelial-myoepithelial carcinoma (EMC), and 1/84 adenoid cystic carcinoma (AdCC). All 84 CXPA cases were analyzed by next-generation sequencing (NGS) and/or fluorescence in situ hybridization (FISH). Forty-three tumors originally diagnosed as CXPA (43/84, 51.2%) showed some molecular alteration. Fusion transcripts were identified in 12/16 (75%) CXPA, including LIFR::PLAG1, CTNNB1::PLAG1, FGFR1::PLAG1 , and a novel fusion, HMGA2::LINC02389 . Most of the fusions were confirmed by FISH using PLAG1 (6/11) and HMGA2 (1/1) gene break probes. Split signals indicating gene break were identified by FISH for PLAG1 (12/17), HMGA2 (3/4), EWSR1 (7/22), and MYB (2/7). Concerning pathogenic mutations, only CXPA with epithelial differentiation (SDC) presented these alterations, including HRAS mutation (2/4), TP53 (1/4), PTEN (1/4), and ATK1 (1/4). In addition, amplifications in ERBB2 (17/35), MDM2 (1/4), and EWSR1 (1/7) were detected. A novel finding was the discovery of an HMGA2::LINC02389 fusion in 1 patient with EMC ex-PA. The present results indicate that molecular profiling of CXPA with myoepithelial differentiation (MC) tends to reveal chromosomal fusion events, whereas CXPA with epithelial differentiation (SDC) tends to have a higher frequency of pathogenic mutations and gene amplifications. Show less

Spindle-cell/sclerosing rhabdomyosarcomas (SS-RMS) are clinically and genetically heterogeneous. They include three well-defined molecular subtypes, of which those with EWSR1/FUS::TFCP2 rearrangements were described only recently. This study aimed to evaluate five new cases of SS-RMS and to perform a clinicopathological and statistical analysis of all TFCP2-rearranged SS-RMS described in the English literature to more comprehensively characterize this rare tumour type. Cases were retrospectively selected and studied by immunohistochemistry, fluorescence in situ hybridization with EWSR1/FUS and TFCP2 break-apart probes, next-generation sequencing (Archer FusionPlex Sarcoma kit and TruSight RNA Pan-Cancer Panel). The PubMed database was searched for relevant peer-reviewed English reports. Five cases of SS-RMS were found. Three cases were TFCP2 rearranged SS-RMS, having FUSex6::TFCP2ex2 gene fusion in two cases and triple gene fusion EWSR1ex5::TFCP2ex2, VAX2ex2::ALKex2 and VAX2intron2::ALKex2 in one case. Two cases showed rhabdomyoblastic differentiation and spindle-round cell/sclerosing morphology, but were characterized by novel genetic fusions including EWSR1ex8::ZBTB41ex7 and PLOD2ex8::RBM6ex7, respectively. In the statistical analysis of all published cases, CDKN2A or ALK alterations, the use of standard chemotherapy and age at presentation in the range of 18-24 years were negatively correlated to overall survival. EWSR1/FUS::TFCP2-rearranged SS-RMS is a rare rhabdomyosarcoma subtype, affecting predominantly young adults with average age at presentation 34 years (median 29.5 years; age range 7-86 years), with a predilection for craniofacial bones, rapid clinical course with frequent bone and lung metastases, and poor prognosis (3-year overall survival rate 28%). Show less

Sudden cardiac death (SCD) in individuals younger than 40 years has a heritable cause in a significant part of the cases. Identification of SCD, post mortem genetic analysis along with the cardiological screening examination in first degree represents an important diagnostic tool for the primary prevention of cardiac arrest in victim´s relatives and requires multicentric and multidisciplinary collaboration. Between 2016 and 2021 the complex cardiogenetic analysis was performed in 115 deaths with post mortem diagnosis of cardiomyopathy, acute aortic dissection and cases without morphological finding explaining the cause of death (sudden arrhythmic death or sudden unexplained death). DNA was isolated from post mortem collected tissue samples or relative´s blood and subjected to massively parallel sequencing (Illumina, USA) in extent of 100 to 20 000 genes. Sequencing results were analysed using the SOPHiA GENETICS DDM bioinformatics platform (Switzerland). Genetic counselling and cardiological examinations were carried out in 328 family members. Highly likely or certain molecular aetiology (i.e. based on presence of ACMG.net Class 4 to 5 variants) was disclosed in 19,8 % of analysed cases in RYR2, KCNH2, KCNQ1, SCN5A, FLNC (stop), GLA, TTN, TNNT2, RBM 20, MYBPC3, MYPN, FHL1, TGFBR1, and COL3A1 genes. With cardiogenetic screening we identified 25 % relatives at risk of life threating arrhythmias and offered them an individualised care. Show less