bims-lifras 2024-08-18 papers

Issue of 2024–08–18
five papers selected by
Joanna Zawacka, Karolinska Institutet

Clin Cancer Res. 2024 Aug 16.

The Impact of Li Fraumeni and Germline Retinoblastoma Mutations on Leiomyosarcoma Initiation, Outcomes and Genetic Testing Recommendations.

Josephine K Dermawan, David H Abramson, Sarah Chiang, Martee L Hensley, William D Tap, Sujana Movva, Robert G Maki, Diana Mandelker, Cristina R Antonescu.

PURPOSE: Leiomyosarcomas (LMS) are clinically and molecularly heterogeneous, occurring mostly in sporadic but also syndromic settings. The role of pathogenic germline variants (PGV) as LMS drivers and impact on outcome remain uncertain.
EXPERIMENTAL DESIGN: We perform a comprehensive clinicopathologic and molecular analysis using a tumor-normal DNA next-generation sequencing assay (MSK-IMPACT) of germline-associated LMS compared to sporadic LMS.
RESULTS: Among 285 LMS [120 soft tissue LMS (STLMS), 165 uterine (ULMS)] with germline testing, 78 (27%, 43 STLMS, 35 ULMS) cases harbored PGV: 35/78 (45%) of PGV carriers showing biallelic inactivation of the corresponding gene in the tumor (26 STLMS, 9 ULMS). The most frequent germline predispositions were TP53 (Li-Fraumeni syndrome) (17 patients, 16 in STLMS) and RB1 (retinoblastoma) (13 patients, 11 in STLMS). Germline TP53 and somatic RB1 alterations often co-occurred in the tumor, and vice versa. Other biallelically inactivated PGV were enriched in DNA damage repair-related genes: CHEK2, MSH2, MSH6, RAD51D, BRCA2 and FANCA. Monoallelic PGV were mostly in ULMS and associated with co-occurring TP53 and RB1 somatic alterations. STLMS patients with biallelic but not monoallelic PGV were significantly younger than sporadic STLMS patients (median ages 38 vs 52 vs 58 years). No differences in disease-specific or progression-free survival were observed in germline-associated vs sporadic LMS, regardless of biallelic status.
CONCLUSIONS: While ULMS patients had a relatively low proportion of PGV, a high percentage of STLMS patients with PGV had tumor biallelic status, indicating that PGV drive tumorigenesis in these individuals. These findings have significant implications for genetic testing recommendations.

DOI: https://doi.org/10.1158/1078-0432.CCR-24-1160

Hemasphere. 2024 Aug;8(8): e145

How to manage patients with germline DDX41 variants: Recommendations from the Nordic working group on germline predisposition for myeloid neoplasms.

Panagiotis Baliakas, Bianca Tesi, Jörg Cammenga, Asbjørg Stray-Pedersen, Kirsi Jahnukainen, Mette Klarskov Andersen, Helena Ågerstam, Maria Creignou, Ingunn Dybedal, Klas Raaschou-Jensen, Kirsten Grønbæk, Outi Kilpivaara, Eva Hellström Lindberg, Ulla Wartiovaara-Kautto.

Increasing recognition of germline DDX41 variants in patients with hematological malignancies prompted us to provide DDX41-specific recommendations for diagnosis, surveillance, and treatment. Causative germline variants in the DDX41 predispose to the development of myeloid neoplasms (MNs), especially myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Almost 3%-5% of all patients with MDS or AML carry a pathogenic or likely pathogenic germline DDX41 variant, while half of them acquire a somatic second hit in the other allele. DDX41-associated MNs exhibit unique clinical characteristics compared to other hematological malignancies with germline predisposition: MNs occur mostly at advanced age and follow an indolent clinical course. Male carriers are more prone to develop MDS or AML than females. DDX41-associated MN is often hypoplastic, and the malignancy may be preceded by cytopenias.

DOI: https://doi.org/10.1002/hem3.145

Int J Hematol. 2024 Aug 16.

Molecular pathophysiology of germline mutations in acute myeloid leukemia.

Yasunobu Nagata.

Germline (GL) predisposition to acute myeloid leukemia (AML) has been established as an independent disease entity in the latest World Health Organization classification. Following the American College of Medical Genetics and Genomics guidelines, GL variants were interpreted as causal if they were classified as "pathogenic." GL predisposition can be divided into three groups with different phenotypes, and play an important role in the pathogenesis of adult-onset AML. The clinical course and age of onset of myeloid neoplasms varied considerably for each gene. For example, patients with GATA2 GL variants develop AML before the age of 30 along with bone marrow failure, whereas those with DDX41 GL variants tend to develop AML after the age of 50 without any preceding hematological abnormalities or organ dysfunction. A comprehensive analysis of adult-onset myelodysplastic syndromes in transplant donors showed a 7% frequency of pathogenic GL variants, with DDX41 being the most frequent gene mutation at approximately 3.8%. Future research on GL predisposition at any age of myeloid neoplasm onset will assist in early and accurate diagnosis, development of effective treatment strategies, and selection of suitable donors for stem cell transplantation.

Keywords: Acute myeloid leukemia; Donor for stem cell transplantations; Germline variants; Mutations; Pathogenic variants

DOI: https://doi.org/10.1007/s12185-024-03824-x

Ann Surg Oncol. 2024 Aug 12.

Development of a Novel Protocol for Germline Testing in Pancreatic Cancer.

BACKGROUND: Guidelines now recommend universal germline genetic testing (GGT) for all pancreatic ductal adenocarcinoma (PDAC) patients. Testing provides information on actionable pathogenic variants and guides management of patients and family. Since traditional genetic counseling (GC) models are time-intensive and GC resources are sparse, new approaches are needed to comply with guidelines without overwhelming available resources.
METHODS: A novel protocol was developed for physician-led GGT. Completed test kits were delivered to the GC team, who maintained a prospective database and mailed all orders. If results revealed pathogenic variants for PDAC, patients were offered comprehensive GC, whereas negative and variant of uncertain significance (VUS) test results were reported to patients via brief calls.
RESULTS: During protocol implementation between January 2020 and December 2022, 310 (81.5%) patients underwent GGT, with a physician compliance rate of 82.6% and patient compliance rate of 98.7%. Of 310 patients tested, 44 (14.2%) patients had detection of pathogenic variants, while 83 (26.8%) patients had VUS. Pathogenic variants included BRCA1/BRCA2/PALB2 (n = 18, 5.8%), ATM (n = 9, 2.9%), CFTR (n = 4, 1.3%), EPCAM/MLH1/MSH2/MSH6/PMS2 (n = 3, 1.0%), and CDKN2A (n = 2, 0.7%). The GC team successfully contacted all patients with pathogenic variants to discuss results and offer comprehensive GC.
CONCLUSION: Our novel protocol facilitated GGT with excellent compliance despite limited GC resources. This framework for GGT allocates GC resources to those patients who would benefit most from GC. As we continue to expand the program, we seek to implement methods to ensure compliance with cascade testing of high-risk family members.

Keywords: Genetic counseling; Germline genetic testing; PDAC; Physician-led genetic testing; Universal genetic testing

DOI: https://doi.org/10.1245/s10434-024-16011-3

Dermatol Pract Concept. 2024 Jul 01. 14(3):

Prevalence of CDKN2A, CDK4, POT1, BAP1, MITF, ATM, and TERT Pathogenic Variants in a Single-Center Retrospective Series of Patients With Melanoma and Personal or Family History Suggestive of Genetic Predisposition.

Giada Ferrara, Salvatore Paiella, Giulio Settanni, Melissa Frizziero, Paolo Rosina, Valeria Viassolo.

INTRODUCTION: Approximately 20%-45% of familial melanoma (FM) cases are associated with genetic predisposition.
OBJECTIVES: This single-center retrospective study aimed to assess the frequency of pathogenic variants (PV) in the main melanoma-predisposing genes in patients with cutaneous melanoma and investigate the clinical predictors of genetic predisposition.
METHODS: Patients included were those diagnosed with cutaneous melanoma at the Dermatology Unit of the University Hospital of Verona, Italy, from 2000 to 2022, presenting at least one of the followings: multiple melanomas (≥ 3); personal/family history of pancreatic cancer (PC) (up to 2nd-degree relatives); ≥ 2 1st-degree relatives with melanoma; ≥ 1 1st-degree relatives with early-onset (<45 years) melanoma and tested for CDKN2A, CDK4, POT1, BAP1, MITF, ATM, and TERT.
RESULTS: During the study period, 35 out of 1320 patients (2.7%) underwent genetic testing. Four patients (11.4%) harbored a PV in a melanoma-predisposing gene, three in CDKN2A (8.6%), and one in MITF (2.9%). Variants currently classified as being of unknown clinical significance (VUS) were detected in CDKN2A (N = 1), MITF (N = 1), and ATM (N = 2). Family history of PC and ≥5 melanomas, personal history of ≥50 nevi, and ≥4 melanomas were significantly associated with PV in tested genes (P < 0.05).
CONCLUSIONS: The prevalence of PV in predisposing genes in FM was lower than previously reported in Italian registries. Possible reasons include deleterious variants in untested intermediate/low-penetrance genes or yet-to-be-discovered high-penetrance genes and environmental risk factors. A family history of PC, a high number of nevi and melanomas predict a monogenic predisposition to melanoma.

DOI: https://doi.org/10.5826/dpc.1403a120