Early Cancer Detection in Li-Fraumeni Syndrome with Cell-Free DNA.

People with Li-Fraumeni syndrome (LFS) harbor a germline pathogenic variant in the TP53 tumor suppressor gene, face a near 100% lifetime risk of cancer, and routinely undergo intensive surveillance protocols. Liquid biopsy has become an attractive tool for a range of clinical applications, including early cancer detection. Here, we provide a proof-of-principle for a multimodal liquid biopsy assay that integrates a targeted gene panel, shallow whole-genome, and cell-free methylated DNA immunoprecipitation sequencing for the early detection of cancer in a longitudinal cohort of 89 LFS patients. Multimodal analysis increased our detection rate in patients with an active cancer diagnosis over uni-modal analysis and was able to detect cancer-associated signal(s) in carriers prior to diagnosis with conventional screening (positive predictive value = 67.6%, negative predictive value = 96.5%). Although adoption of liquid biopsy into current surveillance will require further clinical validation, this study provides a framework for individuals with LFS. SIGNIFICANCE: By utilizing an integrated cell-free DNA approach, liquid biopsy shows earlier detection of cancer in patients with LFS compared with current clinical surveillance methods such as imaging. Liquid biopsy provides improved accessibility and sensitivity, complementing current clinical surveillance methods to provide better care for these patients. See related commentary by Latham et al., p. 23. This article is featured in Selected Articles from This Issue, p. 5.

Genetic predisposition to cancers in children and adolescents.

PURPOSE OF REVIEW: Childhood cancer is rare, but it remains the leading cause of disease-related mortality among children 1-14 years of age. As exposure to environmental factors is lower in children, inherited genetic factors become an important player in the cause of childhood cancer. This review highlights the current knowledge and approach for cancer predisposition syndromes in children. RECENT FINDINGS: Current literature suggests that 10-18% of paediatric cancer patients have an underlying genetic susceptibility to their disease. With better knowledge and technology, more genes and syndromes are being discovered, allowing tailored treatment and surveillance for the probands and their families.Studies have demonstrated that focused surveillance can detect early malignancies and increase overall survival in several cancer predisposition syndromes. Various approaches have been proposed to refine early tumour detection strategies while minimizing the burden on patients and families. Newer therapeutic strategies are being investigated to treat, or even prevent, tumours in children with cancer predisposition. SUMMARY: This review summarizes the current knowledge about different cancer predisposition syndromes, focusing on the diagnosis, genetic counselling, surveillance and future directions.

How essential are in-person clinic visits during maintenance treatment of children with acute lymphoblastic leukemia?

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common cancer in children. Treatment consists of an initial intensive phase of chemotherapy, followed by a prolonged period of maintenance chemotherapy intended to reduce the risk of relapse. During the COVID-19 pandemic, the need arose to identify and reduce non-essential hospital visits. OBJECTIVE: We aimed to determine which proportion of in-person clinic visits during ALL maintenance therapy was associated with a change of management based on the results of the physical examination. PATIENTS AND METHODS: Medical records of children receiving maintenance chemotherapy for B-precursor ALL between September 2019 and February 2020 were reviewed. Visits with a new finding on physical examination were divided into those where an in-person assessment was deemed essential versus not essential. Finally, we determined the proportion of essential in-person visits that resulted in a change of management. RESULTS: A total of 240 maintenance visits by 75 children were analyzed. An abnormal finding on physical examination was noted during 20 visits (8.3%). Of those, 14 (5.8%) uncovered a new finding, six (2.5%) were classified as "in-person visit essential," and among those six visits, three (1.2%) resulted in a change of patient management (one for acute otitis media, one for wheezing, and one for limp). CONCLUSION: Our findings support the evaluation of care delivery models other than in-person visits during ALL maintenance therapy. A prospective study is required to delineate criteria, benefits/risks, and families' perspectives associated with virtual care delivery and the optimal frequency of in-person visits.

Syndromes predisposing to leukemia are a major cause of inherited cytopenias in children.

Prolonged cytopenias are a non-specific sign with a wide differential diagnosis. Among inherited disorders, cytopenias predisposing to leukemia require a timely and accurate diagnosis to ensure appropriate medical management, including adequate monitoring and stem cell transplantation prior to the development of leukemia. We aimed to define the types and prevalences of the genetic causes leading to persistent cytopenias in children. The study comprises children with persistent cytopenias, myelodysplastic syndrome, aplastic anemia, or suspected inherited bone marrow failure syndromes, who were referred for genetic evaluation from all pediatric hematology centers in Israel during 2016-2019. For variant detection, we used Sanger sequencing of commonly mutated genes and a custom-made targeted next-generation sequencing panel covering 226 genes known to be mutated in inherited cytopenias; the minority subsequently underwent whole exome sequencing. In total, 189 children with persistent cytopenias underwent a genetic evaluation. Pathogenic and likely pathogenic variants were identified in 59 patients (31.2%), including 47 with leukemia predisposing syndromes. Most of the latter (32, 68.1%) had inherited bone marrow failure syndromes, nine (19.1%) had inherited thrombocytopenia predisposing to leukemia, and three each (6.4%) had predisposition to myelodysplastic syndrome or congenital neutropenia. Twelve patients had cytopenias with no known leukemia predisposition, including nine children with inherited thrombocytopenia and three with congenital neutropenia. In summary, almost one third of 189 children referred with persistent cytopenias had an underlying inherited disorder; 79.7% of whom had a germline predisposition to leukemia. Precise diagnosis of children with cytopenias should direct follow-up and management programs and may positively impact disease outcome.

Molecular diagnosis of α-thalassemia in a multiethnic population.

OBJECTIVE: α-Thalassemia, one of the most common genetic diseases, is caused by deletions or point mutations affecting one to four α-globin genes. Molecular diagnosis is important to prevent the most severe forms of the disease. However, the diagnosis of α-thalassemia is complex due to a high variability of the genetic defects involved, with over 250 described mutations. We summarize herein the findings of genetic analyses of DNA samples referred to our laboratory for the molecular diagnosis of α-thalassemia, along with a detailed clinical description. METHODS: We utilized a diagnostic algorithm including Gap-PCR, to detect known deletions, followed by sequencing of the α-globin gene, to identify known and novel point mutations, and multiplex ligation-dependent probe amplification (MLPA) for the diagnosis of rare or novel deletions. RESULTS: α-Thalassemia was diagnosed in 662 of 975 samples referred to our laboratory. Most commonly found were deletions (75.3%, including two novel deletions previously described by us); point mutations comprised 25.4% of the cases, including five novel mutations. Our population included mostly Jews (of Ashkenazi and Sephardic origin) and Muslim Arabs, who presented with a higher rate of point mutations and hemoglobin H disease. Overall, we detected 53 different genotype combinations causing a spectrum of clinical phenotypes, from asymptomatic to severe anemia. CONCLUSION: Our work constitutes the largest group of patients with α-thalassemia originating in the Mediterranean whose clinical characteristics and molecular basis have been determined. We suggest a diagnostic algorithm that leads to an accurate molecular diagnosis in multiethnic populations.

Cancer incidence and survival among infants in Israel, 1998-2007.

Cancer during the first year of life is relatively rare and often has clinical and biological properties different from those of the same histologic type of cancer occurring in older children. The aim of this study was to find differences in epidemiology and survival between infants and older children and to compare the percentage of distribution of infant cancer types in Israel with that reported in the United States. We collected infant <1 year of age cases diagnosed between 1998 and 2007 as having cancer from the database of the Israel National Cancer Registry, a total of 309 cases with an incidence rate of 228.5 cases per million. The largest group was diagnosed with neuroblastoma (35%) with an incident rate of 80 per million, followed by leukemia (15.9%), with acute lymphoid leukemia and acute myeloid leukemia accounting for most of this group and central nervous system malignancies comprised 10.7% of infant cancer. One hundred and fifty four new cases of infant girls was diagnosed compared to 155 infant boys with an incidence rates of 234 cases per million for girls and 224.7 for boys, not statistically significant (F:M rate ratio of 1.04). The 5-year survival rates seen in the different groups were leukemia: 55.3%, lymphoma: 71%, CNS tumors: 53.3%, neuroblastoma: 93.4%, retinoblastoma: 94.7% renal tumors: 90.9%, hepatic tumors: 63.3%, soft tissue sarcoma: 76.2%, germ cell neoplasms: 83.3%, and other epithelial neoplasms: 100%. Our study did not find survival differences with statistical significance upon comparing survival rates between different genders and ethnic groups.

Cancer incidence and survival among adolescents in Israel during the years 1998 to 2009.

PURPOSE: Our goal was to describe adolescent cancer incidence and survival in Israel, and to identify demographic and epidemiologic variations among adolescents with cancer. PATIENTS AND METHODS: We used data from the Israel National Cancer Registry in order to examine the incidence and survival of adolescent cancer in Israeli adolescents aged 15-19 years, diagnosed during the years 1998-2009. Cases were analyzed according to sex, ethnicity and geographical region, as well as comparison to other countries in the region and other western countries. RESULTS: Among the 1,532 new cases of adolescent cancer, there was a total incidence rate of 226 cases per million. The incidence rate for males was higher than for females (230 and 222, respectively) and higher for Jewish adolescents than for Arab adolescents (235 and 194, respectively). The largest groups were Lymphomas (69 per million), Malignant Epithelial Neoplasms (49 per million), and Leukemias (21 per million). We estimated the survival probability updated to December 2009, and calculated the 5-year survival for new cases until the end of 2004. The overall survival at 5 years was 78%, with 62% for the Arabic population and 81% for the Jewish population, dependent on the diagnosis. CONCLUSIONS: The results of this study show little difference in the predominance of some adolescent cancers in comparison with other developed countries. This study may add more information for further investigation of the genetic and environmental factors that cause adolescent cancer in Israel. As well as delineate the genetic basis for ethnic origin disparities in survival.

Cancer incidence and survival among children and adolescents in Israel during the years 1998 to 2007.

Our goal was to describe childhood cancer incidence and survival in Israel and to identify demographic and epidemiologic variations among children and adolescents with cancer. We used data from the Israel National Cancer Registry to examine the incidence and survival of pediatric cancer in Israeli children aged 0 to 19 years, diagnosed during the years 1998 to 2007. Cases were analyzed according to sex, age, ethnicity, and geographic region. Among the 4255 cases of childhood cancer, there was a total age-adjusted incidence rate of 172.4 per million for children aged 0 to 19 years and 153.4 per million for children aged 0 to 14 years. The incidence rate for boys was higher than for girls (192.5 and 153.3, respectively) and higher for Jewish children than for Arab children (177.6 and 156.8, respectively). The largest groups were leukemias (22%), lymphomas (20.2%), and central nervous system tumors (17.4%). The number of new cases increased each year, but the incidence rate remained steady. The survival probability updated to December 2008 was estimated and the 5-year survival was calculated for the new cases until the end of 2003. The overall survival at 5 years was 80.8%, with 72.8% for the Arabic population and 83.2% for the Jewish population, and depended on the diagnosis. Incidence and survival in childhood cancer in Israel is at the same medium level compared with other parts of the world. This study may set the basis for investigating the genetic and environmental factors that cause pediatric cancer in Israel, delineating the genetic basis for ethnic origin disparities in survival.