ABSTRACT
Rhabdomyosarcomas (RMS) constitute a heterogeneous spectrum of tumors with respect to clinical behavior and tumor morphology. The paternal uniparental disomy (pUPD) of 11p15.5 is a molecular change described mainly in embryonal RMS. In addition to LOH, UPD, the MLPA technique (ME030kit) also determines copy number variants and methylation of H19 and KCNQ1OT1 genes, which have not been systematically investigated in RMS. All 127 RMS tumors were divided by histology and PAX status into four groups, pleomorphic histology (n = 2); alveolar RMS PAX fusion-positive (PAX+; n = 39); embryonal RMS (n = 70) and fusion-negative RMS with alveolar pattern (PAX-RMS-AP; n = 16). The following changes were detected; negative (n = 21), pUPD (n = 75), gain of paternal allele (n = 9), loss of maternal allele (n = 9), hypermethylation of H19 (n = 6), hypomethylation of KCNQ1OT1 (n = 6), and deletion of CDKN1C (n = 1). We have shown no difference in the frequency of pUPD 11p15.5 in all groups. Thus, we have proven that changes in the 11p15.5 are not only specific to the embryonal RMS (ERMS), but are often also present in alveolar RMS (ARMS). We have found changes that have not yet been described in RMS. We also demonstrated new potential diagnostic markers for ERMS (paternal duplication and UPD of whole chromosome 11) and for ARMS PAX+ (hypomethylation KCNQ1OT1).
Subject(s)
Rhabdomyosarcoma, Alveolar , Rhabdomyosarcoma, Embryonal , Rhabdomyosarcoma , Humans , Rhabdomyosarcoma, Embryonal/genetics , Rhabdomyosarcoma, Embryonal/pathology , Rhabdomyosarcoma/genetics , Rhabdomyosarcoma, Alveolar/genetics , DNA Methylation , Uniparental Disomy , ChromosomesABSTRACT
Molecular assays for translocation detection in different tumors have gradually been incorporated into routine diagnostics. However, conventional methods such as fluorescence in situ hybridization (FISH) and reverse transcriptase-PCR come with several drawbacks. Next-generation sequencing (NGS) can provide in-depth detection of numerous gene alterations. The anchored multiplex PCR assay proved to be a fast and easy-to-analyze approach for routine diagnostics laboratories. Next-generation sequencing-based anchored multiplex PCR technique (Archer FusionPlex Panels) is beneficial in both diagnosis for patient care and in identification of a novel fusion breakpoint in tumors. NGS is useful in identifying targetable molecular changes (point mutations, fusion genes, etc.) in tumors that can serve as a rationale for inclusion of patients with advanced disease in ongoing clinical trials and allow for better risk stratification.
Subject(s)
High-Throughput Nucleotide Sequencing , Neoplasms , Humans , In Situ Hybridization, Fluorescence , Multiplex Polymerase Chain Reaction , Neoplasms/diagnosis , Neoplasms/genetics , Translocation, GeneticABSTRACT
Congenital mesoblastic nephroma (CMN), the most common renal tumor of infancy, is a mesenchymal neoplasm histologically classified into classic, cellular, or mixed types. Most cellular CMNs harbor a characteristic ETV6-NTRK3 fusion. Here, we report an unusual congenital mesoblastic nephroma presenting in a newborn boy with a novel EML4-ALK gene fusion revealed by Anchored Multiplex RNA Sequencing Assay. The EML4-ALK gene fusion expands the genetic spectrum implicated in the pathogenesis of congenital mesoblastic nephroma, with yet another example of kinase oncogenic activation through chromosomal rearrangement. The methylation profile of the tumor corresponds with infantile fibrosarcoma showing the biological similarity of these two entities.
Subject(s)
Fibrosarcoma/genetics , Nephroma, Mesoblastic/genetics , Oncogene Proteins, Fusion/genetics , Proto-Oncogene Proteins c-ets/genetics , Receptor, trkC/genetics , Repressor Proteins/genetics , Fibrosarcoma/diagnosis , Fibrosarcoma/pathology , Humans , In Situ Hybridization, Fluorescence , Infant, Newborn , Male , Nephroma, Mesoblastic/diagnosis , Nephroma, Mesoblastic/pathology , RNA-Seq , ETS Translocation Variant 6 ProteinABSTRACT
PURPOSE: The treatment strategy of parotid gland tumours depends mainly on the histopathological type of the lesion. Fine-needle aspiration biopsy (FNAB) is recommended in preoperative diagnostics. The aim of the study was to evaluate the FNAB standing in the diagnostic algorithm of parotid gland lesions and to correlate FNAB results in relation to the definitive histopathological diagnosis. MATERIAL AND METHODS: The retrospective analyses of 651 examined and consequently surgically treated parotid gland lesions at the Department of Otorhinolaryngology and Head and Neck Surgery, 1st Faculty of Medicine, Charles University in Prague between 2006 and 2016 were used. Preoperative cytological results were consequently evaluated in relation to the definitive histopathological diagnosis. RESULTS: The cohort consisted of 367 women and 284 men (average age 58 years). FNAB was diagnostic in 604 (92.8%) patients and non-diagnostic in 47 (7.2%) patients. The result of FNAB was positive (suspicious for malignant tumour) in 89 (14.7%) patients and negative (benign) in 515 (85.3%) patients. Sensitivity of the examination was 80.00%, specificity was 93.82%, PPV 62.92%, NPV 97.28%, and LR + and LR- were 12.95 and 0.21, respectively, with an accuracy of 92.22%. CONCLUSION: Our results confirm the significant role of FNAB in the diagnostic algorithm of parotid gland lesions.
