Tumor BRCA testing can reveal a high tumor mutational burden related to POLE pathogenic variants.

OBJECTIVE: Tumors harboring a POLE pathogenic variant, associated with high tumor mutational burden, are good candidates for immunotherapy. However, POLE pathogenic variants are not currently screened in routine clinical practice. Can these tumors be identified by means of an already available test? METHODS: We describe seven tumors harboring a POLE pathogenic variant, among eight patients with tumors harboring multiple BRCA1/2 variants (from 4 to 20). All patients were managed at Institut Curie, Paris. Five patients were selected because of unexpected tumor BRCA testing results with multiple variants and another three patients were selected because of a POLE pathogenic variant detected by large tumor testing. We looked for other tumor variants by Next-Generation Sequencing in tumors harboring multiple BRCA1/2 variants, and for multiple BRCA1/2 variants in tumors harboring a POLE pathogenic variant. RESULTS: Four of the five tumors selected because of multiple BRCA1/2 variants exhibited a POLE pathogenic variant, and all three tumors selected for POLE pathogenic variants exhibited multiple BRCA1/2 variants. CONCLUSIONS: Tumor BRCA testing could be a way to detect tumors harboring a highly mutagenic POLE pathogenic variant.

Prognostic value of tumor mutational burden in patients with oral cavity squamous cell carcinoma treated with upfront surgery.

BACKGROUND: Oral cavity is the most prevalent site of head and neck squamous cell carcinomas (HNSCCs). Most often diagnosed at a locally advanced stage, treatment is multimodal with surgery as the cornerstone. The aim of this study was to explore the molecular landscape of a homogenous cohort of oral cavity squamous cell carcinomas (OCSCCs), and to assess the prognostic value of tumor mutational burden (TMB), along with classical molecular and clinical parameters. PATIENTS AND METHODS: One hundred and fifty-one consecutive patients with OCSCC treated with upfront surgery at the Institut Curie were analyzed. Sequencing of tumor DNA from frozen specimens was carried out using an in-house targeted next-generation sequencing panel (571 genes). The impact of molecular alterations and TMB on disease-free survival (DFS) and overall survival (OS) was evaluated in univariate and multivariate analyses. RESULTS: Pathological tumor stage, extranodal spread, vascular emboli, and perineural invasion were associated with both DFS and OS. TP53 was the most mutated gene (71%). Other frequent molecular alterations included the TERT promoter (50%), CDKN2A (25%), FAT1 (17%), PIK3CA (14%), and NOTCH1 (15%) genes. Transforming growth factor-ß pathway alterations (4%) were associated with poor OS (P = 0.01) and DFS (P = 0.02) in univariate and multivariate analyses. High TMB was associated with prolonged OS (P = 0.01 and P = 0.02, in the highest 10% and 20% TMB values, respectively), but not with DFS. Correlation of TMB with OS remained significant in multivariate analysis (P = 0.01 and P = 0.005 in the highest 10% and 20% TMB values, respectively). Pathological tumor stage combined with high TMB was associated with good prognosis. CONCLUSION: Our results suggest that a high TMB is associated with a favorable prognosis in patients with OCSCC treated with upfront surgery.

Loss of SMARCB1 expression in colon carcinoma.

SMARCB1 is a tumor suppressor gene, which is part of SWI/SNF complex involved in transcriptional regulation. Recently, loss of SMARCB1 expression has been reported in gastrointestinal carcinomas. Our purpose was to evaluate the incidence and prognostic value of SMARCB1 loss in colon carcinoma (CC). Patients with stage III CC (n= 1695), and a second cohort of 23 patients with poorly differentiated CC were analyzed. Immunohistochemistry for SMARCB1 was performed on tissue microarrays, and cases with loss of expression were controlled on whole sections. Loss of SMARCB1 was compared with the clinico-pathological and molecular characteristics, and the prognostic value was evaluated. Loss of SMARCB1 was identified in 12 of 1695 (0.7%) patients with stage III CC. Whole section controls showed a complete loss in only one of these cases, corresponding to a medullary carcinoma. SMARCB1 loss was not associated with histological grade, tumor size nor survival. In the cohort of poorly differentiated CC, we detected 2/23 (8.7%) cases with loss of SMARCB1; one was rhabdoid while the other had medullary and mucinous histology. These 2 cases were deficient for MisMatched Repair (dMMR) and mutated for BRAF. SMARCB1 loss is rare in stage III CC, but appears more frequent in poorly differentiated CC.

Efficacy of molecularly targeted agents given in the randomised trial SHIVA01 according to the ESMO Scale for Clinical Actionability of molecular Targets.

BACKGROUND: A randomised trial SHIVA01 compared the efficacy of matched molecularly targeted therapy outside their indications based on a prespecified treatment algorithm versus conventional chemotherapy in patients with metastatic solid tumours who had failed standard of care. No statistical difference was reported between the two groups in terms of progression-free survival (PFS), challenging treatment algorithm. The European Society for Medical Oncology (ESMO) Scale for Clinical Actionability of molecular Targets (ESCAT) recently defined criteria to prioritise molecular alterations (MAs) to select anticancer drugs. We aimed to retrospectively evaluate the efficacy of matched molecularly targeted agents (MTAs) given in SHIVA01 according to ESCAT tiers. PATIENTS AND METHODS: MAs used in SHIVA01 were retrospectively classified into ESCAT tiers, and PFS and overall survival (OS) were compared using log-rank tests. RESULTS: One hundred fifty-three patients were treated with matched MTAs in SHIVA01. MAs used to allocate MTAs were classified into tiers II, IIIA, IIIB and IVA according to the ESCAT. Median PFS was 2.0 months in tier II, 3.1 in tier IIIA, 1.7 in tier IIIB and 3.2 in tier IVA (p = 0.13). Median OS in tier IIIB was worse than that in tiers II, IIIA and IVA (6.3 months versus 11.7, 11.2 and 12.1, p = 0.002). CONCLUSIONS: Most MAs used to allocate therapy in SHIVA01 were shown to improve outcomes in other tumour types (tier IIIA). Worst outcome was observed in patients treated based on another type of alteration than the one reported to improve outcomes (tier IIIB), highlighting the crucial impact of the type of the alterations beyond the gene and the signalling pathway.

[Antiphospholipid antibodies and haemostasis]. / Anticorps antiphospholipides et hémostase.

The antiphospholipid syndrome is characterized by recurrent thrombosis and pregnancy morbidity in association with the persistent presence of autoantibodies called antiphospholipid antibodies. Antiphospholipids are a heterogeneous group of circulating autoantibodies associated with a risk of thrombosis and can paradoxically prolong in vitro the clotting times. In the past few years, significant improvement has been made in understanding the pathophysiologic mechanisms of the disease, thus raising the possibility of future predictive test for the risk of thrombosis. The aim of this review is to make an overview on how the antiphospholipids increase the risk of thrombosis and to provide an update of the laboratory diagnosis and the possible future therapies.

SPRED1 germline mutations caused a neurofibromatosis type 1 overlapping phenotype.

OBJECTIVE: Germline loss-of-function mutations in the SPRED1 gene have recently been identified in patients fulfilling the National Institutes of Health (NIH) diagnostic criteria for neurofibromatosis type 1 (NF1) but with no NF1 (neurofibromin 1) mutation found, suggesting a neurofibromatosis type 1-like syndrome. METHODS: 61 index cases with NF1 clinical diagnosis but no identifiable NF1 mutation were screened for SPRED1 mutation. RESULTS: We describe one known SPRED1 mutation (c.190C>T leading to p.Arg64Stop) and four novel mutations (c.637C>T leading to p.Gln213Stop, c.2T>C leading to p.Met1Thr, c.46C>T leading to p.Arg16Stop, and c.1048_1060del leading to p.Gly350fs) in five French families. Their NF1-like phenotype was characterised by a high prevalence of café-au-lait spots, freckling, learning disability, and an absence of neurofibromas and Lisch nodules in agreement with the original description. However, we did not observe Noonan-like dysmorphy. It is noteworthy that one patient with the p.Arg16Stop mutation developed a monoblastic acute leukaemia. CONCLUSIONS: In our series, SPRED1 mutations occurred with a prevalence of 0.5% in NF1 patients and in 5% of NF1 patients displaying an NF1-like phenotype. SPRED1 mutated patients did not display any specific dermatologic features that were not present in NF1 patients, except for the absence of neurofibromas that seem to be a specific clinical feature of NF1. The exact phenotypic spectrum and the putative complications of this NF1 overlapping syndrome, in particular haematological malignancies, remain to be further characterised. NIH diagnostic criteria for NF1 must be revised in view of this newly characterised Legius syndrome in order to establish a specific genetic counselling.

[Review: delta-storage pool disease]. / Mise au point : la maladie du pool vide plaquettaire.

Platelet storage pool disease is a qualitative platelet disorder associated with variable degrees of reduction in the numbers and contents of dense granules (delta-granules). Electron microscopy is the major tool for biological diagnosis. Patients presenting with this platelet disorder generally show a mild bleeding syndrome.