Non-invasive prenatal screening (NIPS) in twin gestations has been shown to have high detection rates and low false-positive rates for trisomy 21, as seen in singleton pregnancies, although there have been few large cohort twin studies, genome-wide studies in particular, to date. In this study, we looked at the performance of genome-wide NIPT in a large cohort consisting of 1244 twin pregnancy samples collected over a two-year period in a single laboratory in Italy. All samples underwent an NIPS for common trisomies, with 61.5% of study participants choosing to undergo genome-wide NIPS for additional fetal anomalies (namely, rare autosomal aneuploidies and CNVs). There were nine initial no-call results, all of which were resolved upon retest. Based on our NIPS results, 17 samples were at high risk for trisomy 21, one for trisomy 18, six for a rare autosomal aneuploidy, and four for a CNV. Clinical follow-up was available for 27 out of 29 high-risk cases; a sensitivity of 100%, a specificity of 99.9%, and a PPV of 94.4% were noted for trisomy 21. Clinical follow-up was also available for 1110 (96.6%) of the low-risk cases, all of which were true negatives. In conclusion, we found that NIPS was a reliable screening approach for trisomy 21 in twin pregnancies.

Myeloproliferative neoplasms (MPNs) are a heterogeneous group of diseases originating from hematopoietic stem cell transformation, characterized by the clonal proliferation of hematopoietic progenitors. A specific subset includes myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase (TK) gene fusions, particularly involving PDGFR A or B, which are sensitive to TK inhibitor treatment. We report a case of a 21-year-old patient with a myeloproliferative/myelodysplastic neoplasm, presenting with hyperleukocytosis, anemia, thrombocytopenia, and elevated LDH. The peripheral blood smear showed hypogranular neutrophils, eosinophils, basophils, and myeloid precursors. The absence of BCR::ABL1 and mutations in JAK2, CALR, and MPL excluded common MPNs. Cytogenetic analysis revealed a rearrangement between chromosomes 5 and 14. FISH analysis confirmed an inverted insertion from chromosome 5 to chromosome 14, involving the PDGFRB gene. WGS and RNAseq identified a fusion between PDGFRB and CCDC88C, causing the constitutive activation of PDGFRB. The fusion gene was confirmed by sequencing. This allowed for targeted therapy with a tyrosine kinase inhibitor (TKI), leading to molecular remission monitored by RT-qPCR. This case highlights how a multidisciplinary approach can identify atypical transcripts in MPN, guiding targeted therapy with TK inhibitors, thus resulting in effective treatment and molecular remission.

Article: Acuta Genexus: an innovative all-in-one NGS approach for molecular diagnosis of acute myeloid leukemia - Biochimica Clinica 2025 Oct 06 - Minerva Medica - Journals

Acute myeloid leukaemia (AML) is a genetically heterogeneous haematologic malignancy driven by the stepwise acquisition of chromosomal abnormalities and somatic mutations, resulting in clonal evolution. Current guidelines recommend integrating morphology, immunophenotyping, cytogenetics, and molecular analyses for disease classification and prognostic stratification. However, discrepancies between conventional cytogenetics and genome-wide approaches may occur. We describe a 70-year-old man presenting with severe pancytopenia, diagnosed with AML based on bone marrow morphology and immunophenotyping. Karyotyping revealed a deletion of chromosome 11 and additional material on chromosome 12. Targeted Next-Generation Sequencing identified pathogenic variants in FLT3, SF3B1, and EZH2, together with copy number losses involving chromosomes 7 and 11, the former not detected by chromosome banding analysis. To resolve this discrepancy, genome-wide Array-CGH+SNP analysis confirmed monosomy 7 and uncovered additional genomic abnormalities. Fluorescence in situ hybridization (FISH) validated chromosome 7 loss at the single-cell level. Taken together, these findings suggest that monosomy 7 was restricted to a leukaemic subclone underrepresented in metaphase analysis, likely owing to differential proliferative capacity among leukaemic populations. This case highlights how integrated cytogenomic profiling can uncover clinically relevant clonal heterogeneity missed by conventional cytogenetics alone, refining ELN risk stratification and underscoring the value of combining chromosome-based and DNA-based technologies in AML.

Myeloproliferative neoplasms (MPNs) are a heterogeneous group of diseases originating from hematopoietic stem cell transformation, characterized by clonal proliferation of hematopoietic progenitors. A specific subset includes myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase (TK) gene fusions, particularly involving PDGFR A or B, which are sensitive to TK inhibitor treatment. We report a case of a 21-year-old patient with a myeloproliferative/ myelodysplastic neoplasm, presenting with hyperleukocytosis, anemia, thrombocytopenia, and elevated LDH. Peripheral blood smear showed hypogranular neutrophils, eosinophils, basophils, and myeloid precur-sors. Absence of BCR::ABL1 and mutations in JAK2, CALR, and MPL ex-cluded common MPNs. Cytogenetic analysis revealed a rearrangement between chromosomes 5 and 14. FISH analysis confirmed an inverted insertion from chromosome 5 to chromosome 14, involving the PDGFRB gene. WGS and RNAseq identified a fusion between PDGFRB and CCDC88C, causing constitutive activation of PDGFRB. The fusion gene was confirmed by sequencing. This allowed for targeted therapy with a tyrosine kinase inhibitor (TKI), leading to molecular remission monitored by RT-qPCR. This case demonstrates how a multidisciplinary approach can identify atypical transcripts in MPN, guiding targeted therapy with TK inhibitors, resulting in effective treatment and molecular remission.