Revisiting Li-Fraumeni Syndrome From TP53 Mutation Carriers

Nrf2: A key regulator in chemoradiotherapy resistance of osteosarcoma

Osteosarcoma (OS), frequently observed in children and adolescents, is one of the most common primary malignant tumors of the bone known to be associated with a high capacity for invasion and metastasis. The incidence of osteosarcoma in children and adolescents is growing annually, although improvements in survival remain limited. With the clinical application of neoadjuvant chemotherapy, chemotherapy combined with limb-preserving surgery has gained momentum as a major intervention. However, certain patients with OS experience treatment failure owing to chemoradiotherapy resistance or metastasis. Nuclear factor E2-related factor 2 (Nrf2), a key antioxidant factor in organisms, plays a crucial role in maintaining cellular physiological homeostasis; however, its overactivation in cancer cells restricts reactive oxygen species production, promotes DNA repair and drug efflux, and ultimately leads to chemoradiotherapy resistance. Recent studies have also identified the functions of Nrf2 beyond its antioxidative function, including the promotion of proliferation, metastasis, and regulation of metabolism. The current review describes the multiple mechanisms of chemoradiotherapy resistance in OS and the substantial role of Nrf2 in the signaling regulatory network to elucidate the function of Nrf2 in promoting OS chemoradiotherapy resistance and formulating relevant therapeutic strategies.

Update on Cancer Screening Recommendations for Individuals with Li-Fraumeni Syndrome

Li-Fraumeni syndrome (LFS) is an autosomal dominant cancer predisposition condition characterized by a high lifetime risk for a wide spectrum of malignancies associated with germline pathogenic/likely pathogenic variants in the TP53 tumor suppressor gene. Secondary malignant neoplasms are particularly common. Early cancer detection through surveillance enables early intervention and leads to improved clinical outcomes with reduced tumor-related mortality and treatment-related morbidity. Since the 2017 publication of LFS tumor surveillance guidelines from the inaugural American Association for Cancer Research Childhood Cancer Predisposition Workshop, understanding the genotype-phenotype relationships in LFS has evolved, and adaptations of the guidelines have been implemented in institutions worldwide. The "Toronto Protocol" remains the current standard for lifelong surveillance; however, as outlined in this perspective, modifications should be considered about the use of certain modalities to target organs in an age-dependent manner. The Working Group's recommendations have also been extended to include a more detailed outline for surveillance in the adult TP53 pathogenic/likely pathogenic variant carrier population, based on the recognition that early education of both practitioners and patients on what to expect after the transition from childhood/adolescence to young adulthood is important in preparing them for changes in surveillance strategies. In this perspective, we provide an up-to-date clinical overview of LFS and present our updated consensus tumor surveillance recommendations from the 2023 American Association for Cancer Research Childhood Cancer Predisposition Workshop.

Targeting pediatric adrenocortical carcinoma: Molecular insights and emerging therapeutic strategies

Pediatric adrenocortical carcinoma (pACC) is an exceptionally rare and aggressive malignancy, accounting for only 0.2-0.3% of childhood cancers. Characterized by significant endocrine activity and often associated with genetic syndromes such as Li-Fraumeni syndrome, pACC exhibits distinct clinical and molecular profiles compared to adult adrenocortical carcinoma (ACC). Current treatment approaches, largely adapted from adult protocols, center on surgery and chemotherapy, including mitotane. However, the lack of pediatric-specific data and major clinical trials underscores a pressing need for tailored therapeutic strategies. Advances in molecular profiling have unveiled actionable targets, such as alterations in the Wnt/β-catenin and MAP/ERK pathways, overexpression of IGF2, and epigenetic dysregulation. Emerging therapies, including immune checkpoint inhibitors, CAR T-cell therapy, and radiopharmaceuticals, hold promise but remain largely untested in pediatric populations. Targeting metabolic vulnerabilities, such as steroidogenesis and lipid metabolism, offers additional avenues for therapeutic innovation. Furthermore, improved diagnostic tools like liquid biopsy and steroid profiling may enhance disease monitoring and early detection. Despite progress in understanding pACC biology, significant challenges remain in translating these insights into effective treatments. Collaborative efforts, such as the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT), and the development of pediatric-specific clinical trials are vital for advancing the field. Multidisciplinary care and international research initiatives will be pivotal in addressing the unmet needs of pACC patients. By leveraging molecular insights and fostering global collaboration, the field can move toward personalized medicine, improving outcomes and quality of life for children with this challenging disease. Expanding clinical trials, refining diagnostic tools, and integrating novel therapies into treatment regimens will be critical in bridging the gap between pediatric and adult ACC treatment success.

Li-Fraumeni Syndrome : Current Strategies and Future Perspectives

Li-Fraumeni syndrome (LFS) is a rare inherited cancer predisposition syndrome caused by germline mutations in the TP53 tumor suppressor gene. It predisposes affected individuals to a wide spectrum of early-onset malignancies, including sarcomas, breast cancer, brain tumors, and adrenocortical carcinoma. Advances in genetic testing and risk management strategies have enhanced the identification and clinical management of LFS patients. Comprehensive surveillance has demonstrated increased survival rates through proactive screening. Beyond surveillance, research is exploring novel approaches such as liquid biopsy for early cancer detection and chemoprevention strategies, including metformin trials, to mitigate cancer risk. This review discusses the molecular basis, clinical spectrum, surveillance strategies, and emerging research in LFS.

Overt and covert genetic causes of pediatric acute lymphoblastic leukemia

Pediatric acute lymphoblastic leukemia (pALL) is the most common childhood malignancy, yet its etiology remains incompletely understood. However, over the course of three waves of germline genetic research, several non-environmental causes have been identified. Beginning with trisomy 21, seven overt cancer predisposition syndromes (CPSs)-characterized by broad clinical phenotypes that include an elevated risk of pALL-were first described. More recently, newly described CPSs conferring high risk of pALL are increasingly covert, with six exhibiting only minimal or no non-cancer features. These 13 CPSs now represent the principal known hereditary causes of pALL, and human pangenomic data indicates a strong negative selection against mutations in the genes associated with these conditions. Collectively they affect approximately 1 in 450 newborns, of which just a minority will develop the disease. As evidenced by tailored leukemia care protocols for children with trisomy 21, there is growing recognition that CPSs warrant specialized diagnostic, therapeutic, and long-term management strategies. In this review, we investigate the evidence that the 12 other CPSs associated with high risk of pALL may also see benefits from specialized care - even if these needs are often incompletely mapped or addressed in the clinic. Given the rarity of each syndrome, collaborative international research and shared data initiatives will be crucial for advancing knowledge and improving outcomes for these patients.

Genetic predisposition in sarcomas: clinical implications and management

Recent studies indicate up to 20% of sarcomas may be associated with predisposition genes, and this number will probably increase as genetic testing becomes more available. Evidence on the management of patients with sarcoma and genetic predisposition remains, however, scarce. This review compiles available research on genetic predisposition syndromes associated with sarcoma and sarcoma treatment within such syndromes, addressing key gaps in knowledge. We explore the current evidence on how genetic predisposition may influence treatment decisions and clinical management, focusing on surgery, radiotherapy, systemic treatment, and surveillance. Evidence-based recommendations are currently not available for most syndromes, and we have therefore included pragmatic advice for clinicians. Unanswered questions and unmet needs are also identified, underscoring the importance of multidisciplinary input from specialists such as geneticists, radiologists, surgeons and oncologists. The review stresses the need for future research to improve clinical outcomes for patients with sarcoma and genetic predisposition.

Funding

No funding has been provided for this work.

A case of Li-Fraumeni syndrome caused by a 3.6 kb deletion in the TP53 gene suggested by additional data from the NCC Oncopanel

A Japanese woman with Li-Fraumeni syndrome in her 40s underwent comprehensive genetic profiling accompanied by germline data using the Oncoguide NCC Oncopanel, but no germline pathogenic variants in the tumor suppressor gene TP53 were detected. However, careful examination of additional data in the report suggested the presence of a large TP53 deletion. Custom targeting next-generation sequencing and nanopore sequencing revealed a 3.6 kb deletion located between intron 1 and intron 6 of TP53. This finding indicates that the NCC Oncopanel is suggestive for detecting large germline deletions in tumor suppressor genes.

Early-onset Colorectal Cancer in a Patient with Li-Fraumeni Syndrome: A Case Series and Literature Review

Screening for colorectal cancer (CRC) in individuals with Li-Fraumeni syndrome (LFS) typically recommends initiating colonoscopy at 25 years old. We herein report a case of LFS with dual CRC and liver metastasis diagnosed before the recommended screening age. A 17-year-old boy with a history of sarcoma underwent colonoscopy, revealing 2 advanced CRCs: neuroendocrine carcinoma in the descending colon and adenocarcinoma in the rectum, each displaying distinct histological features. In addition, a TP53 missense mutation (p.His193Arg) was detected by a detailed genetic examination. LFS is associated with a heightened risk of rapid progression to invasive carcinomas due to TP53 variants. Therefore, earlier initiation of colonoscopy screening may be necessary for patients with LFS.

Undifferentiated Pleomorphic Sarcoma in Children and Young Adults: A Comprehensive Clinicopathologic, Genomic, and Epigenetic Comparison With Adult Counterparts

Undifferentiated pleomorphic sarcoma (UPS) occurs primarily in older adults and remains a diagnosis of exclusion due to its lack of differentiation and specific molecular alterations. Its occurrence in children is rare and controversial, with an unclear relationship to its adult counterpart. In this study, we aimed to investigate a cohort of 6 pediatric undifferentiated pleomorphic sarcoma (P-UPS, mean 10 years old) and 19 young-adult undifferentiated pleomorphic sarcoma (YA-UPS, mean 30 years old) cases by conducting a comprehensive comparative analysis of their clinicopathologic, genomic, and epigenetic features relative to their adult undifferentiated pleomorphic sarcoma counterparts (A-UPS, n = 100). Histologically, P-UPS and YA-UPS exhibited broad morphologic spectrum. The most frequent alterations across all groups were TP53, CDKN2A/B, and ATRX, with no significant differences among subsets. Notably, RB1 alterations were absent in P-UPS, although representing the second most common alteration in YA-UPS (32%) and A-UPS (41%). PTEN alterations were significantly more prevalent in YA-UPS (26%) compared with that in P-UPS (0%) and A-UPS (6%). Deletions in chromosomes 10, 16q, and 13q, along with amplification of 20q, were the most common across all groups. Except for a higher frequency of 17q amplification in P-UPS (33%) and YA-UPS (26%) compared with that in A-UPS (6%), no other arm-level differences were observed. P-UPS showed a lower mean fraction genome altered compared with YA-UPS and A-UPS, whereas all UPS age groups showed a low tumor mutational burden (mean <10 mut/MB). Pathogenic germline variants of high clinical significance (TP53, NF1, MLH1, CHEK2, and BARD1) were observed only in YA-UPS (31%) and A-UPS (12%) cases. By T-distributed stochastic neighborhood embedding and hierarchical clustering of DNA methylation, the majority of P-UPS and a small subset of YA-UPS grouped in a distinct cluster, characterized by a lower genomic index compared to A-UPS. In contrast, most UPS occurring in young adults genomically parallel their older adults' counterparts. P-UPS and YA-UPS cases exhibited a better disease-specific and progression-free survival, compared with A-UPS cases.

Clinical Sequence Revealed the Prevalence and Biological Significance of Somatic Pathogenic Variants in Thoracic Cancer: Implications for Germline Status

PURPOSE

Presumed germline pathogenic variants (PGPVs) are occasionally detected in thoracic cancer and their frequency and functional significance remain underexplored. We investigated the prevalence and biological significance of PGPVs identified in comprehensive genomic profiling (CGP) panels in patients with thoracic cancer.

PATIENTS AND METHODS

Between January 2021 and August 2023, 204 patients with thoracic cancer were included in this study. A somatic cancer genomic profile system-FoundationOne CDx or an in-house system (Rapid-Neo)-was used for next-generation sequencing-based cancer gene panel tests. Potential PGPVs were identified by evaluating the variant allele frequency (VAF; cutoff > 10%) and pathogenicity based on ClinVar.

RESULTS

PGPVs were detected at a frequency of 9.7% from cohort 1 and 8.1% from cohort 2 in thoracic cancer, based on real-world comprehensive genomic profiling panel testing. Copy number plot did not indicate any homologous recombination deficiency patterns in cases with BRCA1, BRCA2, and RAD51D pathogenic variants in thoracic cancer compared with those in hereditary breast and ovarian cancers. Only one hit of MSH6 pathogenic germline variant was observed for lung cancer tissue in the case of Lynch syndrome; therefore, high tumor mutational burden/microsatellite instability or mismatch repair deficiency was not observed, unlike that in endometrial cancer tissue in the same individual.

CONCLUSION

This study underscores the importance of identifying PGPVs through CGP testing conducted in patients with thoracic cancer. Using frequency and functional analysis. Further investigation is warranted regarding the clinical significance of these PGPVs in managing patients with thoracic cancer and their families.

Characterisation of heritable TP53-related cancer syndrome in Sweden-a nationwide study of genotype-phenotype correlations in 90 families

We aimed to describe the clinical characteristics of families with heritable TP53-related cancer (hTP53rc) syndrome in Sweden with class 4 and 5 germline TP53 variants (gTP53), and to evaluate the genotype-phenotype correlation. These results were also used to evaluate our previously published phenotype prediction model based on TP53 missense variants and their impact on protein conformation. 90 families with hTP53rc were initially identified in Sweden. After variant reclassification using the TP53-specific ACMG criteria, 83 families remained (176 carriers) to harbour a pathogenic (class 5) or likely pathogenic (class 4) variant in TP53. Of these, 112 carriers (64%) had a previous history of cancer, and 35 (31%) had developed more than one primary tumour. 16% of the families met the stricter criteria for Classic Li-Fraumeni syndrome, 45% the updated Chompret criteria, 35% for hereditary breast cancer (HBC), and the remaining 5% were classified as "Others". We identified 42 different gTP53 variants of which 22 were missense. The most frequently observed variant was the missense c.542 G > A, p.R181H identified in 14/29 (48%) of HBC families. Fifteen of the 20 informative missense variants (75%) were phenotypically predicted correctly using our previously published in silico prediction model. The TP53 p.R181H was identified as a common Swedish variant predominantly associated with an HBC phenotype. Apart from this variant, there were no significant genotype-phenotype correlations. Therefore, due to phenotypic overlap it is still too early to stratify surveillance programme for different TP53-carriers.

Risk assessment and genetic counseling for hematologic malignancies-Practice resource of the National Society of Genetic Counselors

Hematologic malignancies (HMs) are a heterogeneous group of cancers impacting individuals of all ages that have been increasingly recognized in association with various germline predisposition syndromes. Given the myriad of malignancy subtypes, expanding differential diagnoses, and unique sample selection requirements, evaluation for hereditary predisposition to HM presents both challenges as well as exciting opportunities in the ever-evolving field of genetic counseling. This practice resource has been developed as a foundational resource for genetic counseling approaches to hereditary HMs and aims to empower genetic counselors who encounter individuals and families with HMs in their practice.

Adjuvant Radiotherapy and Breast Cancer in Patients with Li-Fraumeni Syndrome: A Critical Review

Background/Objectives: Li-Fraumeni syndrome (LFS) is a disease caused by a germline mutation of the tp53 gene that predisposes the individual to various malignancies, including breast cancer. Its impact on treatment modalities in oncology remains poorly studied. In this critical review, we aimed to retrieve and analyze available data concerning adjuvant radiotherapy in early breast cancer for LFS patients, as well as the current guidelines. Methods: We reviewed articles with LFS patient cohorts that reported secondary malignancy rates after breast adjuvant radiotherapy. Rates of recurrence, when available, were also included. Furthermore, we discussed contemporary radiobiological evidence and guidelines on the subject. Results: Six retrospective studies were reviewed. Five reported much higher rates of secondary malignancies compared to the general population. Additionally, there was no clear trend toward increased locoregional control after adjuvant radiotherapy. Radiobiological data suggest increased radioresistance and radiosensitivity within p53-mutated cells. Guidelines recommend avoiding radiotherapy in LFS patients when possible. Conclusions: Currently, there is no standard treatment or cure for LFS or a germline variant of the TP53 gene. With few exceptions, cancers in people with LFS are treated the same way as cancers in other patients, but research continues into the best way to manage cancers involved in LFS.

Multidisciplinary Tumor Board Evaluation of Pediatric Patients with Adrenocortical Tumors Across Seven International Centers

BACKGROUND

The management of rare tumors at reference centers with specialized multidisciplinary tumor boards (MTBs) improves patient survival. No international standardized diagnostic and treatment recommendations for pediatric patients with adrenocortical carcinoma (ACC) exist so far. The aim of this case-based study is to determine how congruent treatment recommendations are in different specialized institutions in different countries.

METHODS

In this cross-sectional, case-based survey study, five anonymized patient cases, including imaging data of pediatric adrenocortical carcinomas (pACCs), were distributed to seven international specialized centers located in Brazil, Germany, India, Italy, Poland, Turkey, and the USA. The centers were tasked with providing recommendations regarding the treatment sequence and modalities, as well as indicating the level of consensus on these decisions within their MTBs. For each case, the treatment approach recommended by the highest number of centers was recorded to calculate an agreement percentage relative to all treatment recommendations made. The consensus level for each case was determined on a scale of 1 to 10, with higher scores indicating greater agreement among MTB members.

RESULTS

A total of five patient cases were discussed across seven MTBs, yielding a total of 34 treatment recommendations. The agreement percentages for the primary therapeutic approach for each case were as follows: primary therapeutic approach: 88.6%; surgical approaches: 51.8%; and systemic chemotherapy recommendations: 53%.

CONCLUSIONS

This study represents the first case-based analysis of international inter-center agreement on pediatric ACC management. Inter-center agreement regarding treatment allocation and sequencing was low, while the level of consensus within each MTB was high. These findings point to potentially significant and clinically relevant differences in treatment standards across centers, highlighting the need for international collaboration and standardized diagnostic and therapeutic recommendations, especially for rare tumors. Increased case-based exchanges between centers are essential to reduce the substantial discrepancies observed here and to further standardize the management of pediatric patients with ACC.

A microglia clonal inflammatory disorder in Alzheimer's disease

Somatic genetic heterogeneity resulting from post-zygotic DNA mutations is widespread in human tissues and can cause diseases, however, few studies have investigated its role in neurodegenerative processes such as Alzheimer's disease (AD). Here, we report the selective enrichment of microglia clones carrying pathogenic variants, that are not present in neuronal, glia/stromal cells, or blood, from patients with AD in comparison to age-matched controls. Notably, microglia-specific AD-associated variants preferentially target the MAPK pathway, including recurrent CBL ring-domain mutations. These variants activate ERK and drive a microglia transcriptional program characterized by a strong neuro-inflammatory response, both in vitro and in patients. Although the natural history of AD-associated microglial clones is difficult to establish in humans, microglial expression of a MAPK pathway activating variant was previously shown to cause neurodegeneration in mice, suggesting that AD-associated neuroinflammatory microglial clones may contribute to the neurodegenerative process in patients.

A systematic review of high-grade glioma associated with Li-Fraumeni syndrome

Li-Fraumeni Syndrome (LFS) is a rare hereditary cancer syndrome characterized by an increased risk of early-onset and multiple tumors across various organ systems, predominantly linked to germline TP53 mutations. While commonly associated neoplasms include sarcomas, breast cancer, and adrenocortical carcinoma, the occurrence of high-grade gliomas (HGG), including glioblastoma multiforme (GBM), in LFS patients is less documented and typically presents at a younger age relative to sporadic cases. A systematic review following PRISMA guidelines was conducted, focusing on clinical studies and case reports that explore the association between HGG and LFS. A comprehensive PubMed search was used to capture relevant studies. The inclusion criteria focused on patients with a confirmed diagnosis of LFS and histopathologically verified HGG. A total of 248 articles were initially identified, with 8 studies meeting the final inclusion criteria after independent review and consensus. Overall, 8 studied reported on patients with either WHO grade 3 or 4 gliomas in the setting of LFS. In total these studies represent 12 patients, with 8 (66%) WHO grade 4, and 4 (33%) WHO grade 3. 9 (75%) patients underwent maximal safe resection, 5 (42%) underwent concurrent TMZ and EBRT. 9 (75%) patients underwent external beam radiation therapy (EBRT), 1 (8%) underwent intensity modulated radiation therapy (IMRT), and 1 (8%) underwent adjuvant treatment with tumor treating fields (TTF) therapy. Overall chemotherapy utilization was 75% with 9 patients receiving some form of chemotherapy. The median time to recurrence following initial treatment was 7 months (IQR: 2.00-7.00). Time to progression was variable, ranging from 5.1 months to 7 years. 64% of patients succumbed to their disease with a median OS of 17 months across studies. LFS associated HGGs are a genetically heterogenous entity. Detailed study of outcomes reported in the literature with respect to these genetics will develop further insight into therapeutic response and prognostication.

Clinical Characteristics and Chemosensitivity in Germline TP53 Pathogenic Variant Cases Identified by Cancer Genomic Testing

BACKGROUND/AIM

The widespread implementation of cancer genomic profiling (CGP) has led to an increase in the detection of germline TP53 pathogenic variants (gTP53v) in patients who do not meet the classical Li-Fraumeni syndrome (LFS) criteria. The present study aimed to characterize the clinical features and treatment outcomes of gTP53v cases identified through routine CGP testing.

PATIENTS AND METHODS

We conducted a retrospective analysis of 43 patients with gTP53v identified through CGP testing between June 2019 and August 2024. Clinical characteristics, molecular features, and treatment outcomes were analyzed and compared with TP53 wild-type cases from the same database (n=6,515).

RESULTS

The median age at diagnosis was 38 years (range=1-83 years), with 58.1% of cases presenting with non-core LFS tumors. A genomic analysis revealed diverse variant types (missense: 32, frameshift: 8, and nonsense: 3) with variant allele frequencies ranging between 0.10 and 0.696. Among 37 patients who received first-line chemotherapy, the objective response rate was 62%, which was significantly higher than in TP53 wild-type cases (32%, p=0.02). Complete responses were observed in six patients and partial responses in 14.

CONCLUSION

The present results suggest that gTP53v carriers identified through CGP represent a broader clinical spectrum than classical LFS, while demonstrating potentially favorable treatment outcomes. These results challenge traditional paradigms and emphasize the need for individualized approaches to patient care, particularly in cases with atypical presentations requiring the careful interpretation of mosaicism, de novo mutations, and clonal hematopoiesis.

Li-Fraumeni syndrome: a germline TP53 splice variant reveals a novel physiological alternative transcript

BACKGROUND

Li-Fraumeni syndrome (LFS) predisposes individuals to a wide range of cancers from childhood onwards, underscoring the crucial need for accurate interpretation of germline TP53 variants for optimal clinical management of patients and families. Several unclassified variants, particularly those potentially affecting splicing, require specialised testing. One such example is the NM_000546.6:c.1101-2A>C (rs587781664) variant, located at the splice acceptor site of the last intron of TP53, identified in a female patient with breast cancer diagnosed in her 20s.

METHODS

To interpret this variant, which has been classified as a variant of uncertain significance (VUS), we developed specific assays including a p53 functional assay, RT-QMPSF, Splice and Expression Analyses by exon Ligation and High-Throughput Sequencing and long RT-droplet digital PCR.

RESULTS

We demonstrated a loss of p53 transcriptional activity, and a half reduction in TP53 mRNA expression. Additionally, we detected the use of a novel alternative last exon downstream of exon 11, which we have named exon 12. This transcript, typically detectable at low levels in most individuals, was found to be more highly expressed in the c.1101-2A>C carrier, predominantly transcribed from the mutant allele due to the disruption of the splice acceptor site in intron 10.

CONCLUSION

By combining these approaches, we successfully reclassified this intronic VUS as 'pathogenic', enabling appropriate genetic counselling for the patient and her family. Additionally, we identified a novel TP53 alternative transcript that is expressed in both physiological and pathological contexts, with heightened expression in the patient with LFS. This discovery provides a basis for further investigation into the role of TP53 isoforms in LFS oncogenesis.

TP53 Deficiency in the Natural History of Prostate Cancer

Prostate cancer remains a leading cause of cancer-related mortality in men, with advanced stages posing significant treatment challenges due to high morbidity and mortality. Among genetic alterations, TP53 mutations are among the most prevalent in cancers and are strongly associated with poor clinical outcomes and therapeutic resistance. This review investigates the role of TP53 mutations in prostate cancer progression, prognosis, and therapeutic development. A comprehensive analysis of preclinical and clinical studies was conducted to elucidate the molecular mechanisms, clinical implications, and potential therapeutic approaches associated with TP53 alterations in prostate cancer. TP53 mutations are highly prevalent in advanced stages, contributing to genomic instability, aggressive tumor phenotypes, and resistance to standard treatments. Emerging evidence supports the utility of liquid biopsy techniques, such as circulating tumor DNA analysis, for detecting TP53 mutations, providing prognostic value and facilitating early intervention strategies. Novel therapeutic approaches targeting TP53 have shown promise in preclinical settings, but their clinical efficacy requires further validation. Overall, TP53 mutations represent a critical biomarker for disease progression and therapeutic response in prostate cancer. Advances in detection methods and targeted therapies hold significant potential to improve outcomes for patients with TP53-mutated prostate cancer. Further research is essential to integrate TP53-based strategies into routine clinical practice.

Re-envisioning genetic predisposition to childhood and adolescent cancers

Although cancer is rare in children and adolescents, it remains a leading cause of death within this age range, and genetic predisposition is the main known risk factor. Since the discovery of retinoblastoma-predisposing RB1 pathogenic germline variants in 1985, several additional high-penetrance cancer predisposition genes (CPGs) have been identified. Although few clinically recognizable genetic conditions display moderate cancer phenotypes, burden testing has revealed low-to-moderate penetrance CPGs. In addition to germline pathogenic variants in CPGs, postzygotic somatic mosaic CPG pathogenic variants acquired during embryonic development are increasingly recognized as factors that predispose children and adolescents to malignancies. Genome-wide association studies of various childhood and adolescent cancer types have identified some common low-risk cancer susceptibility alleles. Although the clinical utility of polygenic risk scores is currently limited in children and adolescents, polygenic risk scores developed for adults can predict subsequent cancer risks in childhood and adolescent cancer survivors. In this Review, I describe our current knowledge of genetic predisposition to childhood and adolescent cancers. Survival rates in children and adolescents with cancer and CPGs are often poor, necessitating better integration of genomic testing into clinical care to improve cancer prevention, surveillance and therapies.

Classification of variants of reduced penetrance in high-penetrance cancer susceptibility genes: Framework for genetics clinicians and clinical scientists by CanVIG-UK (Cancer Variant Interpretation Group-UK)

PURPOSE

Current practice is to report and manage likely pathogenic/pathogenic variants in a given cancer susceptibility gene as though having equivalent penetrance, despite increasing evidence of intervariant variability in risk associations. Using existing variant interpretation approaches, largely based on full-penetrance models, variants in which reduced penetrance is suspected may be classified inconsistently and/or as variants of uncertain significance. We aimed to develop a national consensus approach for such variants within the Cancer Variant Interpretation Group UK (CanVIG-UK) multidisciplinary network.

METHODS

A series of surveys and live polls were conducted during and between CanVIG-UK monthly meetings on various scenarios potentially indicating reduced penetrance. These informed the iterative development of a framework for the classification of variants of reduced penetrance by the CanVIG-UK Steering and Advisory Group working group.

RESULTS

CanVIG-UK recommendations for amendment of the 2015 ACMG/AMP variant interpretation framework were developed for variants in which (A) active evidence suggests a reduced-penetrance effect size (eg, from case-control or segregation data) and (B) reduced penetrance effect is inferred from weaker/potentially inconsistent observed data.

CONCLUSION

CanVIG-UK propose a framework for the classification of variants of reduced penetrance in high-penetrance genes. These principles, although developed for cancer susceptibility genes, are potentially applicable to other clinical contexts.

Bone sarcomas and cancer predisposition syndromes

Bone sarcomas, constituting less than 1% of malignant neoplasms across all age groups, are rare tumours possibly associated with genetic susceptibility syndromes. This review aims to provide recommendations for the detection of cancer predisposition syndromes associated with bone sarcomas and managing affected patients. Recommendations were formulated by a multidisciplinary working and reviewing group from GROUPOS and SFCE oncogenetic's group, including geneticists, oncologists, and radiologists. For various bone sarcomas including osteosarcomas, chondrosarcomas and Ewing sarcomas, we delineate tumour presentation, management strategies, and follow-up within the context of cancer predisposition syndromes. The inherited predisposition syndrome, associated with germline TP53 variants, known as the Li-Fraumeni syndrome, is the most frequent implicated in osteosarcoma cases. Other cancer predisposition syndromes, such as RB1, RECQ or CDKN2A disorders in osteosarcomas and Ollier and Maffucci diseases in chondrosarcomas, are also recognized. Additionally, we discuss rarer cancer predisposition syndromes associated with bone sarcomas and suggest tailored treatment approaches in some cancer predisposition syndromes to mitigate severe toxicities or secondary oncological events. Furthermore, we emphasize the role of identification somatic molecular variations in identifying constitutional germline variants and describe national and international screening programs, reference networks and molecular tumour boards available for collegial and collaborative management discussion. This comprehensive review provides insights into the intricate interplay between genetic predisposition, tumour biology, and therapeutic interventions in bone sarcoma patients with cancer predisposition syndrome.

Exploiting somatic oncogenic driver alterations in a patient with Li-Fraumeni syndrome- paving the path towards precision medicine: a case report

BACKGROUND

Li-Fraumeni syndrome (LFS) is an autosomal dominant tumor predisposition syndrome characterized by a high familial incidence of various malignancies. It results from pathogenic/likely pathogenic heterozygous constitutional variants of the TP53 gene. Due to impaired DNA damage repair, conventional cytotoxic therapies or radiotherapy should be avoided whenever feasible to mitigate the high incidence of treatment-related secondary malignancies in these patients. However, there is limited evidence supporting the effectiveness of targeted therapy approaches in LFS patients.

CASE PRESENTATION

We present the case of a woman with breast cancer and subsequent osteosarcoma, both treated with surgery and chemotherapy. Constitutional genetic germline testing identified a pathogenic TP53 variant in line with the clinical features of Li-Fraumeni syndrome. Subsequent molecular analysis of the osteosarcoma tissue revealed homozygous loss of the CDKN2A gene locus, warranting treatment with CDK4/6 inhibitor palbociclib. Palbociclib therapy was discontinued after one year with no evidence of disease. One year later, ovarian cancer was diagnosed, with molecular analysis indicating interstitial heterozygous loss of the BRCA2 gene locus, providing a rationale for targeted therapy with the PARP inhibitor olaparib.

CONCLUSIONS

In the era of accessible and comprehensive genetic and phenotypic tumor profiling, this case study of a patient with Li-Fraumeni syndrome underscores the success of precision oncology in harnessing additional somatic oncogenic driver alterations. Furthermore, it emphasizes the indispensable role of an interdisciplinary molecular tumor board, enhancing the awareness of molecular profiling and targeted therapies in patients with rare cancer susceptibility disorders.

TP53 germline testing and hereditary cancer: how somatic events and clinical criteria affect variant detection rate

BACKGROUND

Germline heterozygous pathogenic variants (PVs) in TP53 cause Li-Fraumeni syndrome (LFS), a condition associated with increased risk of multiple tumor types. As the associated cancer risks were refined over time, clinical criteria also evolved to optimize diagnostic yield. The implementation of multi-gene panel germline testing in different clinical settings has led to the identification of TP53 PV carriers outside the classic LFS-associated cancer phenotypes, leading to a broader cancer phenotypic redefinition and to the renaming of the condition as "heritable TP53-related cancer syndrome" (hTP53rc). Germline TP53 variant interpretation is challenging due to the diverse nature of TP53 PVs, variable penetrance of the syndrome, possible occurrence of TP53 somatic mosaicism, and TP53 involvement in clonal hematopoiesis of indeterminate potential (CHIP). Here we aim to assess the relevance and impact of these issues on the diagnostic routine, and to evaluate the sensitivity of the different LFS clinical criteria to identify hTP53rc.

METHODS

TP53 was analyzed in 6161 suspected hereditary cancer non-related patients categorized into three subgroups: (1) 495 patients fulfilling any LFS/Chompret clinical criteria; (2) 2481 patients diagnosed with early-onset breast/colorectal cancer; (3) 3185 patients without clinical criteria suggestive of hTP53rc. Ancillary tests were performed when TP53 PVs were identified in individuals not meeting LFS/Chompret criteria and/or when the variant was identified at low variant allele frequency (VAF).

RESULTS

TP53 PVs were identified in blood DNA of 45 probands. Variant origin was elucidated in 39 of these: 72% patients had a constitutional PV, 10% were mosaics, and 18% had CHIP-associated PVs. Notably, two of the seven CHIP-TP53 PVs identified were detected at high allelic frequencies (VAF > 35%). Twenty-nine percent of germline TP53 PV did not meet any of the LFS clinical criteria. Among the clinical criteria, Chompret 2009 showed the highest sensitivity in our cohort (68% vs. 54% for Chompret 2015), highlighting the relevance of considering lung cancer in the criteria.

CONCLUSIONS

Our data supports performing TP53 ancillary testing for the identification of potential mosaicisms and CHIP-associated PVs, particularly in patients not meeting clinical criterial for LFS, irrespective of the VAF, and the application of clinical criteria that include lung cancer diagnosis.

Cancer risk in carriers of TP53 germline variants grouped into different functional categories

Li-Fraumeni syndrome is a cancer predisposition syndrome caused by pathogenic TP53 germline variants; it is associated with a high lifelong cancer risk. We analyzed the German Li-Fraumeni syndrome registry, which contains data on 304 individuals. Cancer phenotypes were correlated with variants grouped according to their ability to transactivate target genes in a yeast assay using a traditional (nonfunctional, partially functional) and a novel (clusters A, B, and C) classification of variants into different groups. Partially functional and cluster B or C variants were enriched in patients who did not meet clinical testing criteria. Time to first malignancy was longer in carriers of partially functional variants (hazard ratio = 0.38, 95% CI = 0.22 to 0.66). Variants grouped within cluster B (hazard ratio = 0.45, 95% CI = 0.28 to 0.71) or C (hazard ratio = 0.34, 95% CI = 0.19 to 0.62) were associated with later cancer onset than NULL variants. These findings can be used to risk-stratify patients and inform care.

Adrenocortical tumors and hereditary syndromes

INTRODUCTION

Adrenocortical tumors (ACTs) are frequently encountered in clinical practice. They vary in clinical and biological characteristics from nonfunctional to life threatening hormone excess, from benign to highly aggressive malignant tumors. Most ACTs appear to be benign and nonfunctioning. It has been controversial how these apparently benign and nonfunctioning tumors should be monitored. Over the past few decades, significant advances have been made in understanding the regulation of growth and tumorigenesis in adrenocortical cells. Defining the molecular pathomechanisms in inherited tumor syndromes led to the expansion of research to sporadic ACTs. Distinct molecular signatures have been identified in sporadic ACTs and a potential genomic classification of ACT has been proposed.

AREAS COVERED

In this review, we discuss the various adrenocortical pathologies associated with hereditary syndromes with special focus on their molecular pathomechanisms, the understanding of which is important in the era of precision medicine.

EXPERT OPINION

Identifying the molecular pathomechanisms of the adrenocortical tumorigenesis in inherited syndromes has led to the understanding of the alterations in different signaling pathways that help explain the wide variations in the biology and behavior of ACTs.

Germline genetic mutations in a multi-center cohort of 248 phyllodes tumors

PURPOSE

Germline genetic mutations in women with phyllodes tumors (PT) are understudied, although some describe associations of PT with various mutations. We sought to determine the prevalence of pathogenic/likely pathogenic (P/LP) variants in women with PT.

METHODS

A 6-site multi-center study of women with a PT was initiated, then expanded nationally through an online "Phyllodes Support Group." All women underwent 84-gene panel testing. We defined eligibility for testing based on select NCCN (National Comprehensive Cancer Network) criteria (v1.2022). Logistic regression was used to estimate the association of covariates with the likelihood of a P/LP variant.

RESULTS

274 women were enrolled: 164 (59.9%) through multi-center recruitment and 110 (40.1%) via online recruitment. 248 women completed testing; overall 14.1% (N = 35) had a P/LP variant, and over half (N = 19) of these individuals had a mutation in genes associated with autosomal dominant (AD) cancer conditions. The most common AD genes with a P/LP variant included CHEK2, ATM, and RAD51D. A quarter of participants (23.8%) met NCCN criteria for testing, but we found no difference in prevalence of a P/LP variant based on eligibility (p = 0.54). After adjustment, the presence of P/LP variants was not associated with age, NCCN testing eligibility, or PT type (all p > 0.05).

CONCLUSION

Our study demonstrates that 7.7% of women with PT harbor germline P/LP variants in genes associated with AD cancer conditions. Early identification of these variants has implications for screening, risk reduction, and/or treatment. National guidelines for women with PT do not currently address germline genetic testing, which could be considered.

Clustering of TP53 variants into functional classes correlates with cancer risk and identifies different phenotypes of Li-Fraumeni syndrome

Li-Fraumeni syndrome (LFS) is a heterogeneous predisposition to an individually variable spectrum of cancers caused by pathogenic TP53 germline variants. We used a clustering method to assign TP53 missense variants to classes based on their functional activities in experimental assays assessing biological p53 functions. Correlations with LFS phenotypes were analyzed using the public germline TP53 mutation database and validated in three LFS clinical cohorts. Class A carriers recapitulated all phenotypic traits of fully penetrant LFS, whereas class B carriers showed a slightly less penetrant form dominated by specific cancers, consistent with the notion that these classes identify variants with distinct functional properties. Class C displayed a lower lifetime cancer risk associated with attenuated LFS features, consistent with the notion that these variants have hypomorphic features. Class D carriers showed low lifetime cancer risks inconsistent with LFS definitions. This classification of TP53 variants provides insights into structural/functional features causing pathogenicity.

New Germline TP53 Variant Detected After Radiotherapy-Induced Angiosarcoma of the Chest Wall in a Previously Treated Breast Cancer Patient: A Case Report and Review of Li-Fraumeni Syndrome and Radiotherapy-Induced Sarcoma

Li-Fraumeni syndrome (LFS) is one of the most common hereditary cancer predisposition syndromes in Brazil. The high frequency of the syndrome is due to a founding variant (R337H) in the country. LFS is characterized by a wide variety of malignant phenotypes. Despite the great epidemiological importance of the R337H variant, the frequency of other types of pathogenic variants is like other populations, with the majority of these being missense variants. There is strong evidence that radiotherapy is associated with secondary sarcomas, including angiosarcomas, and this finding is especially true for LFS patients. Angiosarcoma is not described as overrepresented in individuals with LFS, except in patients submitted to radiotherapy. Germline testing in all breast cancer patients under 65 will reveal many germline mutations in TP53 without a family history of cancers associated with the syndrome. We present a case of a previously undescribed pathogenic variant in TP53 (c788del, pAns263llefs⁣∗82) in a patient with no family history of cancer, with a previous diagnosis of breast carcinoma treated with radiotherapy, who developed angiosarcoma after a few years leading to germline testing. The presence of angiosarcoma in a radiotherapy bed should raise suspicion for LFS. The recent recommendation of testing breast cancer patients under the age of 65, even without any family history, can be a source of discoveries of new mutations and assist in therapeutic decisions.

Are TP53 mutations all alike?

TP53 is mutated in 10 to 15% of cases of acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) and is associated with a previous exposure to cytotoxic therapy, complex cytogenetic abnormalities, and a poor prognosis. Recent data have established the importance of TP53-mutant allele status, the determination of which requires specific genetic testing. Compared with monoallelic disease, multihit TP53-mutant AML/MDS is associated with chromosomal abnormalities and decreased overall survival. Most TP53 mutations are missense mutations that localize to the DNA binding domain. Hot-spot mutations involving residues R175, Y220, G245, R248, R273, or R282 represent approximately 35% of all TP53 missense mutations in AML/MDS. There is evidence that these hot-spot mutations may have dominant negative or gain-of-function properties. Here we review this evidence and discuss its potential impact on patient outcomes and clinical management.

Multi-omics profiling highlights karyopherin subunit alpha 2 as a promising biomarker for prognosis and immunotherapy respond in pediatric and adult adrenocortical carcinoma

PURPOSE

Adrenocortical carcinoma (ACC) afflicts both pediatric and adult populations and is characterized by dismal prognosis and elevated mortality. Given the inconsistent therapeutic benefits and significant side effects associated with the conventional chemotherapy agent, mitotane, and the nascent stage of immunotherapy and targeted treatments, there is an urgent need to identify novel prognostic biomarkers and therapeutic targets in ACC.

METHODS

Utilizing multi-omic datasets from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO), we employed Weighted Gene Co-expression Network Analysis (WGCNA), Cox regression, Receiver Operating Characteristic (ROC) curves, and survival analyses to sift for potential prognostic biomarkers. We subsequently validated these findings through immunohistochemistry and cell assays, and delved into the biological role of KPNA2 in ACC through functional enrichment analysis, mutational landscape, and immune cell infiltration.

RESULTS

A total of 77 progression-associated genes with aberrant chromosomal accessibility were discerned within the TCGA-ACC dataset. By integrating ROC and Cox regression from GEO datasets, KPNA2 emerged as an independent risk factor portending poor outcomes in ACC. ATAC-seq analysis revealed attenuated chromatin accessibility of KPNA2 in cases with unfavorable prognosis. Immunohistochemistry corroborated elevated KPNA2 expression, which was linked to enhanced proliferation and invasion. Elevated KPNA2 levels were found to activate oncogenic pathways while simultaneously suppressing immunological responses. Immune infiltration analysis further revealed a decrement in CD8+ T-cell infiltration in KPNA2-high cohorts.

CONCLUSION

This study demonstrates the clinical and biological significance of KPNA2 in ACC and suggests that KPNA2 could serve as a promising biomarker for predicting prognosis and immunotherapeutic responses in pediatric and adult ACC patients.

Li-Fraumeni-associated osteosarcomas: The French experience

PURPOSE

Describe clinical characteristics and outcome of Li-Fraumeni syndrome (LFS)-associated osteosarcomas.

METHODS

TP53 germline pathogenic/likely pathogenic variant carriers diagnosed with osteosarcoma in France between 1980 and 2019 were identified via the French Li-Fraumeni database at Rouen University Hospital. Sixty-five osteosarcomas in 52 patients with available clinical and histological data were included. The main clinical characteristics were compared with data from National Cancer Institute's SEER (Surveillance, Epidemiology, and End Results) for patients of the same age group.

RESULTS

Median age at first osteosarcoma diagnosis was 13.7 years (range: 5.9-36.7). Compared to unselected osteosarcomas, LFS-associated osteosarcomas occurred more frequently in patients less than 10 years of age (23% vs. 9%), and when compared with osteosarcomas in patients less than 25 years were characterized by an excess of axial (16% vs. 10%) and jaw sites (15% vs. 3%) and histology with predominant chondroblastic component and periosteal subtypes (17% vs. 1%). Metastases incidence (25%) was as expected in osteosarcomas. After the first osteosarcoma treatment, the rate of good histologic response (62%) and the 5-year progression-free survival (55%, 95% confidence interval [CI]: 42.6-71.1) were as expected in unselected series of osteosarcomas, whereas the 5-year event-free survival was 36.5% [95% CI: 25.3-52.7] due to the high incidence of second malignancies reaching a 10-year cumulative risk of 43.4% [95% CI: 28.5-57.5].

CONCLUSION

In osteosarcoma, young age at diagnosis, axial and jaw sites, histology with periosteal or chondroblastic subtype, and synchronous multifocal tumors should prompt suspicion of a germline TP53 mutation. Standard treatments are effective, but multiple malignancies impair prognosis. Early recognition of these patients is crucial for tailored therapy and follow-up.

DNA Mismatch Repair Deficiency as a Biomarker in Sarcoma

Purpose

Lynch syndrome (LS) is a cancer predisposition syndrome caused by a germline loss-of-function mutation in a mismatch repair (MMR) gene. While sarcomas are not classically considered LS cancers, we investigated the MMR status and clinical features of sarcomas in LS patients to help inform optimal treatment strategies.

Methods

A prospectively maintained institutional clinical cancer genetics database was queried for LS patients (defined by pathogenic germline mutation in a MMR gene) with a documented diagnosis of sarcoma between 1998-2022. Tumor MMR status was determined by immunohistochemistry (IHC) for MMR proteins and secondarily by PCR assay if IHC was normal or intact.

Results

Among the 30 LS patients with sarcoma, germline mutations were most common in MSH2 (50%). The most common sarcoma subtypes were undifferentiated pleomorphic sarcoma (40%) and leiomyosarcoma (27%). Median age at diagnosis was 49.2 years (interquartile range 40.4-62.4). 90% presented with localized disease, and 10% presented with synchronous metastatic disease. Among 10 patients with tissue available for biomarker determination, dMMR was confirmed in 4 (40%), while the remaining (60%) were pMMR. Three patients received immunotherapy. Two of these had confirmed dMMR tumor status: one demonstrated a sustained complete response on pembrolizumab monotherapy for 44 months; the other had a partial response on ipilimumab and nivolumab for 31 months but died from an unrelated cause. In the entire cohort of 30 patients at a median follow-up time of 68.2 months since sarcoma diagnosis (interquartile range 29.0-151.5 months), median overall survival and progression-free survival have not been reached.

Conclusion

While rare, sarcoma can be encountered in patients with LS, particularly those with germline MSH2 mutation. LS-associated sarcomas occur significantly earlier, carry a favorable outcome, and demonstrate the potential for durable response with immunotherapy.

Prostate cancer and genetic contributions

Prostate cancer remains a lethal disease for many men. Knowledge of genetic contributions to this condition has increasingly been used in its management. In this narrative review, we summarize various genetic alterations and syndromes associated with prostate cancer, including hereditary breast and ovarian cancer syndrome, Lynch syndrome, and hereditary prostate cancer, among others. Indications for germline testing are reviewed, as well as incorporation of genetic data at different phases of management for prostate cancer, such as screening and monitoring, and treatment of localized and metastatic disease.

The Importance of Genetic Screening on the Syndromes of Colorectal Cancer and Gastric Cancer: A 2024 Update

Gastrointestinal cancers (GIC), encompassing colonic, rectal, and gastric malignancies, rank among the most prevalent cancer types globally, contributing significantly to cancer-related mortality. In the scientific literature, various syndromes associated with colorectal and gastric cancers have been elucidated, highlighting the intricate interplay between genetic factors and disease manifestation. The primary objective of this study was to conduct a genetic exploration aimed at elucidating these associations and identifying shared genetic determinants across these cancer types. Notably, considerable research has focused on the KRAS gene mutations, polymorphisms in nucleic acids, the Wnt signaling pathway, and the role of chemokine ligands in tumorigenesis. While investigations into natural plant extracts as potential therapeutic agents are still in their nascent stages, they represent a promising avenue for future research. Ongoing studies are essential to uncover suitable biomarkers that could facilitate the identification and understanding of the genetic links between these GIC. This exploration not only seeks to enhance our comprehension of the underlying genetic architecture but also aims to inform the development of targeted therapies and preventive strategies.

Complexity in interpreting cardiac valve-associated thrombus from tumors in Li-Fraumeni syndrome

Li-Fraumeni syndrome (LFS) is a well-defined autosomal dominant predisposition syndrome due to TP53 germline mutation that causes many cancer malignancies. This early-onset syndrome poses a state of widespread malignancy. Such an inherited condition possessing defective p53, guardian of the genome, in the germline has the potential to cause multiple cancers by predominantly affecting mesenchyme (connective tissues, blood cells), breast, brain, and adrenal cortex organs. The tumors initially identified in LFS can eventually propagate to cause secondary malignancies. LFS contributes to multiple cancers in individuals with defective p53 inheritance. When suspected to possess any mass, patients with other co-morbidities, in particular those with certain cardiovascular conditions, undergo screening using high-throughput techniques like transthoracic and transesophageal echocardiography or cardiothoracic magnetic resonance imaging to locate and interpret the size of the mass. In LFS cases, it is certain to presume these masses as cancers and plan their management employing invasive surgeries after performing all efficient diagnostic tools. There are only poor predictions to rule out the chances of any other pathology. This criterion emphasizes the necessity to speculate alternative precision diagnostic methods to affirm such new growth or masses encountered in LFS cases. Moreover, it has all the possibilities to ultimately influence surgical procedures that may be invasive or complicate operative prognosis. Hence, it is essential to strategize an ideal protocol to diagnose any new unexplored mass in the LFS community. In this editorial, we discuss the importance of diagnostic approaches on naïve pristine masses in LFS.

Clinical and genetic characteristics of carriers of the TP53 c.541C > T, p.Arg181Cys pathogenic variant causing hereditary cancer in patients of Arab-Muslim descent

TP53 pathogenic variants cause Li-Fraumeni syndrome (LFS), with some variants causing an attenuated phenotype. Herein, we describe the clinical phenotype and genetic characteristics of carriers of NM_000546.6 (TP53): c.541C > T, (p.Arg181Cys) treated at Hadassah Medical Center. We retrospectively examined our genetic databases to identify all carriers of TP53 p.Arg181Cys. We reached out to carriers and their relatives and collected clinical and demographic data, lifestyle factors, carcinogenic exposures as well as additional blood samples for genetic testing and whole exome sequencing. Between 2005 and 2022 a total of 2875 cancer patients underwent genetic testing using genetic panels, whole exome sequencing or targeted TP53 assays. A total of 30 cancer patients, all of Arab-Muslim descent, were found to be carriers of TP53 p.Arg181Cys, the majority from Jerusalem and Hebron, two of which were homozygous for the variant. Carriers were from 24 distinct families of them, 15 families (62.5%) met updated Chompret criteria for LFS. Median age of diagnosis was 35 years-old (range 1-69) with cancers characteristic of LFS (16 Breast cancer; 6 primary CNS tumors; 3 sarcomas) including 4 children with choroid plexus carcinoma, medulloblastoma, or glioblastoma. A total of 21 healthy carriers of TP53 p.Arg181Cys were identified at a median age of 39 years-old (range 2-54)-19 relatives and 2 additional pediatric non-cancer patients, in which the finding was incidental. We report a shared haplotype of 350kb among carriers, limited co-morbidities and low BMI in both cancer patients and healthy carriers. There were no demographic factors or carcinogenic exposures unique to carriers who developed malignancy. Upon exome analysis no other known pathogenic variants in cancer predisposing genes were identified. TP53 p.Arg181Cys is a founder pathogenic variant predominant to the Arab-Muslim population in Jerusalem and Hebron, causing attenuated-LFS. We suggest strict surveillance in established carriers and encourage referral to genetic testing for all cancer patients of Arab-Muslim descent in this region with LFS-associated malignancies as well as family members of established carriers.

New Paradigms in the Clinical Management of Li-Fraumeni Syndrome

Approximately 8.5%-16.2% of childhood cancers are associated with a pathogenic/likely pathogenic germline variant-a prevalence that is likely to rise with improvements in phenotype recognition, sequencing, and variant validation. One highly informative, classical hereditary cancer predisposition syndrome is Li-Fraumeni syndrome (LFS), associated with germline variants in the TP53 tumor suppressor gene, and a >90% cumulative lifetime cancer risk. In seeking to improve outcomes for young LFS patients, we must improve the specificity and sensitivity of existing cancer surveillance programs and explore how to complement early detection strategies with pharmacology-based risk-reduction interventions. Here, we describe novel precision screening technologies and clinical strategies for cancer risk reduction. In particular, we summarize the biomarkers for early diagnosis and risk stratification of LFS patients from birth, noninvasive and machine learning-based cancer screening, and drugs that have shown the potential to be repurposed for cancer prevention.

Germline p.R181H variant in TP53 in a family exemplifying the genotype-phenotype correlations in Li-Fraumeni syndrome

Li-Fraumeni syndrome (LFS) is a cancer predisposition syndrome associated with germline pathogenic/likely pathogenic variants in TP53. Genotype-phenotype correlations are progressively being characterized in LFS with certain TP53 variants associated with attenuated penetrance and phenotypes. We report on a family harboring a TP53 p.R181H variant presenting with a restricted cancer phenotype in adulthood. The proband was a female with breast cancer at the age of 71 years who had three first degree relatives also diagnosed with breast cancer after the age of 40 years (mother, two sisters). Of the nine individuals harboring the variant (6 genetically confirmed, 3 obligate heterozygous), six have not developed malignancies at this time (age range: 36-42). No childhood-onset cancers were reported in this family. A concomitant literature review identified 51 additional individuals harboring the p.R181H variant in TP53, presenting a tumor phenotype dominated by breast cancer. Rare occurrences of other adult-onset cancers (prostate, colorectal and thyroid) and only few childhood onset cancer were documented. These observations are consistent with functional analysis showing that p.R181H retains partial p53 function and suggesting possible reduced cancer penetrance, particularly in the pediatric setting.

Current insights and future directions of Li-Fraumeni syndrome

Li-Fraumeni syndrome is a rare yet serious hereditary cancer predisposition syndrome, marked by a significant early-life increased risk of developing cancer. Primarily caused by germline mutations in the TP53 tumor suppressor gene, Li-Fraumeni syndrome is associated with a wide range of malignancies. Clinical management of Li-Fraumeni syndrome could be challenging, especially the lifelong surveillance and follow-up of patients which requires a multidisciplinary approach. Emerging insights into the molecular and clinical basis of Li-Fraumeni syndrome, coupled with advances in genomic technologies and targeted therapies, offer promise in optimizing risk assessment, early detection, and treatment strategies tailored to the unique clinical and molecular profiles of affected individuals. This review discusses Li-Fraumeni syndrome in more depth, reviewing molecular, genomic, epidemiological, clinical, and therapeutic aspects of this disease.

Bioinformatic Characterization of the Functional and Structural Effect of Single Nucleotide Mutations in Patients with High-Grade Glioma

Background: Gliomas are neoplasms of the central nervous system that originate in glial cells. The genetic characteristics of this type of neoplasm are the loss of function of tumor suppressor genes such as TP53 and somatic mutations in genes such as IDH1/2. Additionally, in clinical cases, de novo single nucleotide polymorphisms (SNP) are reported, of which their pathogenicity and their effects on the function and stability of the protein are known. Methodology: Non-synonymous SNPs were analyzed for their structural and functional effect on proteins using a set of bioinformatics tools such as SIFT, PolyPhen-2, PhD-SNP, I-Mutant 3.0, MUpro, and mutation3D. A structural comparison between normal and mutated residues for disease-associated coding SNPs was performed using TM-aling and the SWISS MODEL. Results: A total of 13 SNPs were obtained for the TP53 gene, 1 SNP for IDH1, and 1 for IDH2, which would be functionally detrimental and associated with disease. Additionally, these changes compromise the structure and function of the protein; the A161S SNP for TP53 that has not been reported in any databases was classified as detrimental. Conclusions: All non-synonymous SNPs reported for TP53 were in the region of the deoxyribonucleic acid (DNA) binding domain and had a great impact on the function and stability of the protein. In addition, the two polymorphisms detected in IDH1 and IDH2 genes compromise the structure and activity of the protein. Both genes are related to the development of high-grade gliomas. All the data obtained in this study must be validated through experimental approaches.

Osteosarcoma patient with Li-Fraumeni syndrome: the first case report in Vietnam

Li-Fraumeni syndrome (LFS) is a hereditary disorder characterized by an increased risk of developing multiple early-onset cancers, primarily due to germline TP53 mutations. Women and men with this mutation face lifetime cancer risks of 90% and 70%, respectively. This report describes the first documented case of LFS with clinical information in Vietnam involving a 9-year-old child diagnosed with osteosarcoma who had multiple first- and second-degree relatives with cancer. Whole-genome sequencing (WGS) revealed a heterozygous, pathogenic, autosomal dominant TP53 variant NM_000546.6:c.733G>A (p.Gly245Ser) and a translocation in the 3'UTR of the ATMIN gene with unknown pathogenicity in both the patient and her mother. Sanger sequencing confirmed the presence of the TP53 c.733G>A mutation, which was subsequently detected in extended family members. Of the 17 family members invited for testing, only 8, none of whom currently have cancer, agreed to participate: all tested negative for the mutation. This case highlights the importance of genetic testing for the early detection and management of cancers in LFS patients. It also underscores significant barriers to genetic screening in Vietnam, including limited access and the psychosocial consequences of testing, which emphasize the need for improved genetic counseling and surveillance strategies that are tailored to local contexts.

Novel case of ependymoma-like tumor with mesenchymal differentiation harboring ZFTA::RELA fusion in an adult

High-grade supratentorial tumors harboring ZFTA::NCOA1/2 fusion in infants presenting with mixed histology of embryonal-appearing components resembling ependymoma and mesenchymal sarcomatous components have recently been reported as ependymoma-like tumors with mesenchymal differentiation (ELTMDs). In contrast, we describe herein a pathologically similar case with a novel ZFTA::RELA fusion in an adult. A frontal lobe lesion was resected from a 30-year-old woman and displayed mixed components on pathological examination, showing ependymoma-like and sarcomatous parts. The absence of perivascular pseudorosettes was inconsistent with a diagnosis of ependymoma. Fluorescence in situ hybridization analysis confirmed ZFTA::RELA fusion. The DKFZ methylation classifier (v12.8) did not categorize this case among established methylation classes. In addition, t-distributed stochastic neighbor embedding analysis using DNA methylation data revealed that the present case was distant from ependymomas but close to two previously reported cases of ELTMD involving ZFTA::NCOA1/2 fusion. Taken together, we concluded that this tumor should be considered under the entity of ELTMD. This represents the first description of an adult patient with ELTMD harboring ZFTA::RELA fusion analyzed by DNA methylation profiling, supporting the establishment of ELTMD as a possible new tumor type.

Molecular pathophysiology of germline mutations in acute myeloid leukemia

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.

Advances in pathogenesis research and challenges in treatment development for acute myeloid leukemia

Acute myeloid leukemia (AML) develops when hematopoietic stem cells acquire chromosomal and genetic abnormalities, transforming into leukemia stem cells (LSCs) and further gaining driver mutations. Advances in genomic analysis have identified numerous new gene mutations involved in AML development. Recent research has shown that individuals with germline mutations in genes like DDX41 and CEBPA develop AML upon acquiring additional somatic mutations, and the latest WHO classification separates AML with such mutations into distinct disease groups. LSCs are regulated by different metabolic processes than normal stem cells, contributing to drug resistance and relapse. LSCs rely on oxidative phosphorylation (OXPHOS) metabolism for energy production, and venetoclax inhibits this process, affecting LSCs. Resistant LSCs show enhanced glycolysis, which suggests that targeting both OXPHOS and glycolysis is crucial. While targeted therapies like FLT3, BCL-2, and IDH inhibitors have shown efficacy, resistance remains an issue, highlighting the need for new treatment strategies. CAR-T cell therapy is an emerging immunotherapy that shows particular promise for targeting CD123 and CLL-1, with acceptable toxicity. Future developments in CAR-T cell therapy and other immunotherapies are anticipated to improve AML treatment outcomes.

Germline DNA Damage Repair Gene Alterations in Patients with Metachronous Breast and Colorectal Cancer

A hereditary component of breast (BC) and colorectal cancer (CRC) has been described in approximately one-third of these tumor types. BC patients have an increased risk of developing CRC as a second primary tumor and vice versa. Germline genomic variants (NextSeq550, Illumina) were investigated in 24 unrelated BC and/or CRC patients and 7 relatives from 3 index patients. Fifty-six pathogenic or likely pathogenic variants were identified in 19 of 24 patients. We detected single-nucleotide variants (SNVs) in CRC predisposition genes (MLH1 and MUTYH) and other promising candidates (CDK5RAP3, MAD1L1, NOS3, and POLM). Eighteen patients presented SNVs or copy number variants (CNVs) in DNA damage repair genes. We also identified SNVs recently associated with BC or CRC predisposition (PABPC1, TYRO3, MAP3K1, SLC15A4, and LAMA1). The PABPC1c.1255C>T variant was detected in nine unrelated patients. Each patient presented at least one SNV/CNV in a candidate gene, and most had alterations in more than one gene, reinforcing a polygenic model for BC/CRC predisposition. A significant fraction of BC/CRC patients with a family history of these tumors harbored deleterious germline variants in DNA repair genes. Our findings can lead to strategies to improve the diagnosis, genetic counseling, and treatment of patients and their relatives.