Familial uveal melanoma and other tumors in 25 families with monoallelic germline MBD4 variants.

Background: Monoallelic germline MBD4 pathogenic variants were recently reported to cause a predisposition to uveal melanoma, associated with a specific tumor mutational signature and good response to immunotherapy. Monoallelic tumor pathogenic variants have also been described in brain tumors, breast cancers, and myxofibrosarcomas, whereas biallelic germline MBD4 pathogenic variants have been involved in a recessive hereditary adenomatous polyposis and a specific type of acute myeloid leukemia.

Methods: We analyzed MBD4 for all patients with a diagnosis of uveal melanoma at Institut Curie since July 2021 and in the 3240 consecutive female probands explored at the Institut Curie for suspicion of predisposition to breast cancer between July 2021 and February 2023.

Diagnosis of PTEN mosaicism: the relevance of additional tumor DNA sequencing. A case report and review of the literature.

Background: PTEN hamartoma syndrome (PHTS) is an autosomal dominant disorder characterized by pathogenic variants in the tumor suppressor gene phosphatase and tensin homolog (PTEN). It is associated with an increased risk of muco-cutaneous features, hamartomatous tumors, and cancers. Mosaicism has been found in a few cases of patients with de novo PHTS, identified from blood samples.

PTEN alterations in sporadic and BRCA1-associated triple negative breast carcinomas.

The similarities between sporadic basal-like breast cancer (BLBC) and BRCA1-mutated breast tumours raise the possibility that deregulation of the same pathway may underlie these tumour types. The aim of this study was to determine if PTEN aberrations are characteristic of both BRCA1 tumours and sporadic TN breast carcinomas with low BRCA1 expression, and can thus be used to identify sporadic tumours potentially sensitive to PARP inhibitors. Twelve BRCA1 tumours, 19 non-BRCA familial breast tumours and 71 unselected TN breast carcinomas were screened for PTEN mutations and assessed for PTEN expression and BRCA1 mRNA expression.

Increased incidence of pathogenic variants in ATM in the context of testing for breast and ovarian cancer predisposition.

Pathogenic Variants (PV) in major cancer predisposition genes are only identified in approximately 10% of patients with Hereditary Breast and Ovarian Cancer (HBOC) syndrome. Next Generation Sequencing (NGS) leads to the characterization of incidental variants in genes other than those known to be associated with HBOC syndrome. The aim of this study was to determine if such incidental PV were specific to a phenotype.

Classification of 101 BRCA1 and BRCA2 variants of uncertain significance by cosegregation study: A powerful approach.

Up to 80% of BRCA1 and BRCA2 genetic variants remain of uncertain clinical significance (VUSs). Only variants classified as pathogenic or likely pathogenic can guide breast and ovarian cancer prevention measures and treatment by PARP inhibitors. We report the first results of the ongoing French national COVAR (cosegregation variant) study, the aim of which is to classify BRCA1/2 VUSs.

TUMOSPEC: A Nation-Wide Study of Hereditary Breast and Ovarian Cancer Families with a Predicted Pathogenic Variant Identified through Multigene Panel Testing.

Assessment of age-dependent cancer risk for carriers of a predicted pathogenic variant (PPV) is often hampered by biases in data collection, with a frequent under-representation of cancer-free PPV carriers. TUMOSPEC was designed to estimate the cumulative risk of cancer for carriers of a PPV in a gene that is usually tested in a hereditary breast and ovarian cancer context. Index cases are enrolled consecutively among patients who undergo genetic testing as part of their care plan in France.

Combined tumor genomic profiling and exome sequencing in a breast cancer family implicates ATM in tumorigenesis: A proof of principle study.

Familial breast cancers (BCs) account for 10%-20% of all diagnosed BCs, yet only 20% of such tumors arise in the context of a germline mutation in known tumor suppressor genes such as BRCA1 or BRCA2. The vast genetic heterogeneity which characterizes non BRCA1 and non BRCA2 (or BRCAx) families makes grouped studies impossible to perform. Next generation sequencing techniques, however, allow individual families to be studied to identify rare and or private mutations but the high number of genetic variants identified need to be sorted using pathogenicity or recurrence criteria.

Insertion of Alu elements at a PTEN hotspot in Cowden syndrome.

Cowden syndrome (CS) is an inherited autosomal dominant disorder associated with germline pathogenic variants of the PTEN tumor suppressor gene. Its phenotypical expression is highly variable and the existence of patients with a CS suggestive phenotype without pathogenic PTEN variant may be related to genetic heterogeneity. In order to explore this hypothesis through the detection of potentially deleterious variants enabling us to identify a new candidate gene, we performed whole-exome sequencing (WES) in a series of 22 CS patients without detectable PTEN pathogenic variant using conventional methods for mutation screening.

Long clinical benefit achieved in two patients with malignant paraganglioma treated by metronomic cyclophosphamide.

Treatment of malignant paraganglioma remains a challenge with an overall 5-year survival rate between 34 and 60%. Systemic treatment is recommended in case of unresectable malignant paraganglioma. Recent advances in molecular biology provided rationale to use antiangiogenic agents in this setting.

[Hereditary ovarian carcinomas: clinico-biological features and treatment].

Hereditary ovarian cancers account for 10% of all cases. Two major syndromes with dominant autosomal transmission are identified. The most common one is breast-ovarian cancer syndrome due to BRCA1 and BRCA2 genes mutations, and the Lynch syndrome with mutated MMR genes is the other.

High cumulative risks of cancer in patients with PTEN hamartoma tumour syndrome.

Background: PTEN hamartoma tumour syndrome (PHTS) encompasses several clinical syndromes with germline mutations in the PTEN tumour suppressor gene, including Cowden syndrome which is characterised by an increased risk of breast and thyroid cancers. Because PHTS is rare, data regarding cancer risks and genotype-phenotype correlations are limited. The objective of this study was to better define cancer risks in this syndrome with respect to the type and location of PTEN mutations.