Severe and Rare Case of Human Dirofilaria repens Infection with Pleural and Subcutaneous Manifestations, Slovenia.

We report a case of human Dirofilaria repens infection in a woman in Slovenia who had concomitant pleural and subcutaneous manifestations of the infection. This case report illustrates the clinical course of a severe symptomatic parasitic infection that had multisystemic manifestations.

Papillary thyroid carcinoma with prominent myofibroblastic stromal component: clinicopathologic, immunohistochemical and next-generation sequencing study of seven cases.

Papillary thyroid carcinoma with desmoid-type fibromatosis or nodular fasciitis-like stroma is an extremely unusual and poorly understood subtype of papillary thyroid cancer. Although prior studies have demonstrated alterations in the Wnt/ß-catenin signaling pathway in some of these tumors, controversy still exists regarding the nature of the stromal spindle component. We have studied seven cases of papillary thyroid carcinoma with prominent myofibroblastic stroma, including six men and one woman aged 20-65 years (mean age = 44). All cases displayed areas consistent with conventional papillary thyroid carcinoma embedded in abundant myofibroblastic-like stroma. The myofibroblastic stroma in six cases resembled desmoid-type fibromatosis and in one case it more closely resembled nodular fasciitis. By immunohistochemical staining, the stromal spindle component showed positivity for SMA and low MIB1 proliferation index in all cases, and there was at least patchy strong nuclear positivity for beta-catenin in six/seven cases. Stains for cytokeratin AE1/AE3 and PAX8 were positive in the epithelial elements but negative in the stromal component. Next-generation sequencing was performed on six of seven cases. CTNNB1 gene mutations were identified in six/seven cases. The epithelial component showed BRAF mutations in two cases and an NRAS mutation in one case. The case with fasciitis-like stroma was negative for beta-catenin by sequencing and immunostaining as well as negative for USP6 gene rearrangement. Our findings indicate that papillary thyroid carcinoma with prominent myofibroblastic stroma may represent more than one category of lesions.

A Population-Based Study of Patients With Small Cell Carcinoma of the Ovary, Hypercalcemic Type, Encompassing a 30-Year Period.

CONTEXT.­: Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is a rare and lethal tumor, characterized by hypercalcemia and early onset and associated with germline and somatic SMARCA4 variants. OBJECTIVE.­: To identify all known cases of SCCOHT in the Slovenian population from 1991 to 2021 and present genetic testing results, histopathologic findings, and clinical data for these patients. We also estimate the incidence of SCCOHT. DESIGN.­: We conducted a retrospective analysis of hospital medical records and data from the Slovenian Cancer Registry in order to identify cases of SCCOHT and obtain relevant clinical data. Histopathologic review of tumor samples with assessment of immunohistochemical staining for SMARCA4/BRG1 was undertaken to confirm the diagnosis of SCCOHT. Germline and somatic genetic analyses were performed using targeted next-generation sequencing. RESULTS.­: Between 1991 and 2021, we identified 7 cases of SCCOHT in a population of 2 million. Genetic causes were determined in all cases. Two novel germline loss-of-function variants in SMARCA4 LRG_878t1:c.1423_1429delTACCTCA p.(Tyr475Ilefs*24) and LRG_878t1:c.3216-1G>T were identified. At diagnosis, patients were ages 21 to 41 and had International Federation of Gynecology and Obstetrics, or FIGO, stage IA-III disease. Outcomes were poor, with 6 of 7 patients dying of disease-related complications within 27 months from diagnosis. One patient had stable disease for 12 months while receiving immunotherapy. CONCLUSIONS.­: We present genetic, histopathologic, and clinical characteristics for all cases of SCCOHT identified in the Slovenian population during a 30-year period. We report 2 novel germline SMARCA4 variants, possibly associated with high penetrance. We estimate the minimal incidence of SCCOHT to be 0.12 per 1 million per year.

Post-radiation xerostomia therapy with allogeneic mesenchymal stromal stem cells in patients with head and neck cancer: study protocol for phase I clinical trial.

BACKGROUND: Xerostomia is a common side effect of radiotherapy in patients with head and neck tumors that negatively affects quality of life. There is no known effective standard treatment for xerostomia. Here, we present the study protocol used to evaluate the safety and preliminary efficacy of allogeneic mesenchymal stromal stem cells (MSCs) derived from umbilical cord tissue. PATIENTS AND METHODS: Ten oropharyngeal cancer patients with post-radiation xerostomia and no evidence of disease recurrence 2 or more years after (chemo)irradiation (intervention group) and 10 healthy volunteers (control group) will be enrolled in this nonrandomized, open-label, phase I exploratory study. MSCs from umbilical cord tissue will be inserted under ultrasound guidance into both parotid glands and both submandibular glands of the patients. Toxicity of the procedure will be assessed according to CTCAE v5.0 criteria at days 0, 1, 5, 28, and 120. Efficacy will be assessed by measuring salivary flow and analyzing its composition, scintigraphic evaluation of MSC grafting, retention, and migration, and questionnaires measuring subjective xerostomia and quality of life. In addition, the radiological, functional, and morphological characteristics of the salivary tissue will be assessed before, at 4 weeks, and at 4 months after the procedure. In the control group subjects, only salivary flow rate and salivary composition will be determined. DISCUSSION: The use of allogeneic MSCs from umbilical cord tissue represents an innovative approach for the treatment of xerostomia after radiation. Due to the noninvasive collection procedure, flexibility of cryobanking, and biological advantages, xerostomia therapy using allogeneic MSCs from umbilical cord tissue may have an advantage over other similar therapies.

Integrative Transcriptomic Profiling of the Wilms Tumor.

Our study aimed to identify relevant transcriptomic biomarkers for the Wilms tumor, the most common pediatric kidney cancer, independent of the histological type and stage. Using next-generation sequencing, we analyzed the miRNA profiles of 74 kidney samples, which were divided into two independent groups: fresh frozen tissue and formalin-fixed paraffin-embedded tissue samples. Subsequent mRNA expression profiling and pathway analysis were performed to establish the interplay and potential involvement of miRNAs and mRNA in the Wilms tumor. Comparative analysis, irrespective of post-dissection tissue processing, revealed 41 differentially expressed miRNAs, with 27 miRNAs having decreased expression and 14 miRNAs having increased expression in the Wilms tumor tissue compared to healthy kidney tissue. Among global mRNA transcriptomic profile differences, cross-sectional analysis suggested a limited list of genes potentially regulated by differentially expressed miRNAs in the Wilms tumor. This study identified the comprehensive miRNA and mRNA profile of the Wilms tumor using next-generation sequencing and bioinformatics approach, providing better insights into the pathogenesis of the Wilms tumor. The identified Wilms tumor miRNAs have potential as biomarkers for the diagnosis and treatment of the Wilms tumor, regardless of histological subtype and disease stage.

NUT Carcinoma: A Clinical, Morphological and Immunohistochemical Mimicker-The Role of RNA Sequencing in the Diagnostic Procedure.

Background: NUT carcinoma is a highly aggressive and rare subset of squamous cell carcinoma with grim prognosis. It is under-recognized by both pathologists and oncologists. Recognition is challenging due to its rareness and the fact that its clinical and laboratory features as well as morphological and immunohistochemical characteristics may mimic other malignancies. Case presentation: An interesting case of NUT carcinoma in a 47-year-old male with a large tumor mass in the inferior part of the mediastinum and left lung and increased levels of serum alpha fetoprotein (AFP) is described. Immunohistochemical analysis of both the primary tumor in a bronchoscopy specimen and an excisional biopsy of a subcutaneous metastasis showed positivity for AFP and leukocyte common antigen (LCA) that were misleading and resulted in diagnostic pitfalls of mediastinal germ cell tumor (clinically) and hematolymphoid neoplasm (pathologic report). Immunohistochemical demonstration of NUT protein expression revealed the proper diagnosis, which was further confirmed by RNA sequencing revealing a BRD4-NUTM1 gene fusion.Conclusions: Since NUT carcinoma can show a wide spectrum of histological and immunophenotypic features and can clinically mimic other tumors, use of RNA sequencing with identification of specific NUTM1 fusion partner could be crucial when there are discrepant clinical and histopathological findings. As well, since the category of so-called NUTM1-rearranged neoplasms is rapidly expanding, identification of NUTM1 fusion partner may be essential for the appropriate clinical management.

Correlation of treatment outcome in sanger/RT­qPCR KIT/PDGFRA wild­type metastatic gastrointestinal stromal tumors with next­generation sequencing results: A single­center report.

In patients with gastrointestinal stromal tumors (GIST), it has become mandatory to determine the driver mutation in order to predict the response to standard treatment with tyrosine kinase inhibitors (TKI). A total of 10­15% of all GIST lack activating mutations in KIT proto­oncogene, receptor tyrosine kinase (KIT)/platelet­derived growth factor receptor alpha (PDGFRA) and have been classified as KIT/PDGFRA wild­type (WT) GIST. They are characterized by poor response to TKI. From a group of 119 metastatic GIST patients, 17 patients with KIT/PDGFRA/BRAF WT GIST as determined by reverse transcription­quantitative (RT­q) PCR and Sanger sequencing were profiled by a targeted next­generation sequencing (NGS) approach and their treatment outcome was assessed. In the present study, 41.2% of patients as KIT/PDGFRA/BRAF WT GIST examined with RT­qPCR and Sanger sequencing were confirmed to be carriers of pathogenic KIT/PDGFRA mutations by NGS and were responsive to TKI. The percentage of genuinely KIT/PDGFRA WT GIST in the present study thereby dropped from the initial 14.3% detected with the RT­qPCR and Sanger sequencing to 7.6% after NGS. Their outcome was universally poor. The reliability of RT­qPCR and direct Sanger sequencing results in this setting is therefore insufficient and it is recommended that NGS becomes a requirement for treatment decision at least in KIT/PDGFRA/BRAF WT GIST as determined by RT­qPCR and Sanger sequencing.

A Novel Germline MLH1 In-Frame Deletion in a Slovenian Lynch Syndrome Family Associated with Uncommon Isolated PMS2 Loss in Tumor Tissue.

The diagnostics of Lynch syndrome (LS) is focused on the detection of DNA mismatch repair (MMR) system deficiency. MMR deficiency can be detected on tumor tissue by microsatellite instability (MSI) using molecular genetic test or by loss of expression of one of the four proteins (MLH1, MSH2, MSH6, and PMS2) involved in the MMR system using immunohistochemistry (IHC) staining. According to the National Comprehensive Cancer Network (NCCN) guidelines, definitive diagnosis of LS requires the identification of the germline pathogenic variant in one of the MMR genes. In the report, we are presenting interesting novel MLH1 in-frame deletion LRG_216t1:c.2236_2247delCTGCCTGATCTA p.(Leu746_Leu749del) associated with LS. The variant appears to be associated with uncommon isolated loss of PMS2 immunohistochemistry protein staining (expression) in tumor tissue instead of MLH1 and PMS2 protein loss, which is commonly seen with pathogenic variants in MLH1. The variant was classified as likely pathogenic, based on segregation analysis and molecular characterization of blood and tumor samples. According to the American College of Medical Genetics (ACMG) guidelines, the following evidence categories of PM1, PM2, PM4, and PP1 moderate have been used for classification of the novel variant. By detecting and classifying the novel MLH1 variant as likely pathogenic, we confirmed the LS in this family.

Two Novel NF1 Pathogenic Variants Causing the Creation of a New Splice Site in Patients With Neurofibromatosis Type I.

Neurofibromatosis type I (NF1) is one of the most common autosomal dominant disorders, since the estimated incidence is one in 3,500 births. In this study, we present bioinformatical and functional characterization of two novel splicing NF1 variants, detected in NF1 patients. Patient 1, carrying NF1:c.122A>T, which introduces a new exonic 5' donor splice site, was diagnosed with hormone-positive, Her-2-negative breast cancer at the age of 47. She had an atypical presentation of NF1, with few café-au-lait spots and no Lisch nodules. Patient developed a hemothorax due to subclavian artery rupture, which has previously been described as an extremely rare complication of NF1. Patient 2, carrying NF1:c.7395-17T>G that creates a new intronic 3' acceptor splice site, had quite a typical clinical presentation of NF1: formations on her tongue in the region of her left metacarpal bones and on her left foot, plexiform neurofibroma in her pelvis, several café-au-lait spots, and axillary freckling. She was also diagnosed with cognitive impairment. In the report, we are presenting two novel variants which were successfully classified based on NGS and mRNA analysis. Based on results of mRNA analysis, both variants were classified as likely pathogenic according to ACMG guidelines applying evidence categories PS3, PM2, PP3, and PP1 supporting. By characterizing those two novel NF1 splicing variants, we have confirmed the neurofibromatosis type I phenotype in the two probands.

In inverted papillomas HPV more likely represents incidental colonization than an etiological factor.

Inverted papillomas (IPs) are the most frequent type of sinonasal papillomas. These benign but destructive lesions are known for their high recurrence rate, probably due to incomplete excision. Our aim was to investigate the frequency of human papillomavirus (HPV) infection in patients with IPs and in IPs associated with squamous cell carcinoma (IPsSCC) and to compare it with the frequency of HPV infections in the control group. The influence of HPV infection on the malignant alteration and recurrence rate of IPs was also evaluated. Paraffin-embedded tissue samples from 68 patients with sinonasal IPs and 5 patients with IPsSCC were analyzed in this retrospective study. The control group consisted of 47 patients who had undergone septoplasty or mucotomy of the inferior turbinate. PCR amplification with consensus primer sets was performed to detect alpha-HPVs, and direct sequencing of the PCR products with the same primers was used to determine the HPV genotypes in the samples. We detected HPV DNA in 20 (30.3%) patients with IPs, in 3 (60%) patients with IPsSCC, and in 6 (13%) patients from the control group. The frequency of HPV infection in the study group was statistically significantly higher (p = 0.032) than in the control group. The presence of HPV DNA was not a statistically significant predictor of the recurrence of IPs (p = 0.745) nor was it a statistically significant risk factor for associated SCC (p = 0.32). Since HPV type 11 was the predominant genotype in the IPs, IPsSCC, and in the control cases, we presume that HPV infection may represent incidental colonization rather than being an important etiological factor of IPs.