Candidate driver genes involved in genome maintenance and DNA repair in Sézary syndrome.

Sézary syndrome (SS) is a leukemic variant of cutaneous T-cell lymphoma (CTCL) and represents an ideal model for study of T-cell transformation. We describe whole-exome and single-nucleotide polymorphism array-based copy number analyses of CD4(+) tumor cells from untreated patients at diagnosis and targeted resequencing of 101 SS cases. A total of 824 somatic nonsynonymous gene variants were identified including indels, stop-gain/loss, splice variants, and recurrent gene variants indicative of considerable molecular heterogeneity. Driver genes identified using MutSigCV include POT1, which has not been previously reported in CTCL; and TP53 and DNMT3A, which were also identified consistent with previous reports. Mutations in PLCG1 were detected in 11% of tumors including novel variants not previously described in SS. This study is also the first to show BRCA2 defects in a significant proportion (14%) of SS tumors. Aberrations in PRKCQ were found to occur in 20% of tumors highlighting selection for activation of T-cell receptor/NF-κB signaling. A complex but consistent pattern of copy number variants (CNVs) was detected and many CNVs involved genes identified as putative drivers. Frequent defects involving the POT1 and ATM genes responsible for telomere maintenance were detected and may contribute to genomic instability in SS. Genomic aberrations identified were enriched for genes implicated in cell survival and fate, specifically PDGFR, ERK, JAK STAT, MAPK, and TCR/NF-κB signaling; epigenetic regulation (DNMT3A, ASLX3, TET1-3); and homologous recombination (RAD51C, BRCA2, POLD1). This study now provides the basis for a detailed functional analysis of malignant transformation of mature T cells and improved patient stratification and treatment.

Thrombotic risk in COVID-19: a case series and case-control study.

BACKGROUND: A possible association between COVID-19 infection and thrombosis, either as a direct consequence of the virus or as a complication of inflammation, is emerging in the literature. Data on the incidence of venous thromboembolism (VTE) are extremely limited. METHODS: We describe three cases of thromboembolism refractory to heparin treatment, the incidence of VTE in an inpatient cohort, and a case-control study to identify risk factors associated with VTE. RESULTS: We identified 274 confirmed (208) or probable (66) COVID-19 patients. 21 (7.7%) were diagnosed with VTE. D-dimer was elevated in both cases (confirmed VTE) and controls (no confirmed VTE) but higher levels were seen in confirmed VTE cases (4.1 vs 1.2 µg/mL, p<0.001). CONCLUSION: Incidence of VTE is high in patients hospitalised with COVID-19. Urgent clinical trials are needed to evaluate the role of anticoagulation in COVID-19. Monitoring of D-dimer and anti-factor Xa levels may be beneficial in guiding management.

Real-world experience of ibrutinib therapy in relapsed chronic lymphocytic leukemia: results of a single-center retrospective analysis.

BACKGROUND: Ibrutinib is a Bruton's tyrosine-kinase (BTK) inhibitor that is approved as a second-line treatment in chronic lymphocytic leukemia (CLL). While recent trials have demonstrated impressive results for ibrutinib, there remains a paucity of real-world data on its use in the clinical setting. METHODS: In this single-center study carried out at Brighton and Sussex University Hospitals, we retrospectively compared outcomes in 38 patients with relapsed CLL who received ibrutinib versus those who received conventional first- and second-line therapies. RESULTS: Our results demonstrate improved progression-free survival (PFS, p=0.022) with ibrutinib versus conventional second-line therapies and survival comparable to conventional first-line therapies. However, there was a high frequency (81.6%) of adverse events associated with ibrutinib therapy, including 2 cases of death secondary to sepsis and a further 7 cases of discontinuation of treatment due to adverse events. We also identify del13q14.3 as an adverse predictor of response to ibrutinib with respect to both overall survival (p=0.014) and PFS (p=0.008), suggesting that these patients may be better suited to receiving the BCL2 inhibitor venetoclax. CONCLUSION: Whilst there is robust evidence for improved outcomes with ibrutinib, we find that survival in patients with del13q14.3 is reduced and that the rate of adverse events and discontinuation in clinical practice is higher than anticipated from clinical trials.