A novel tandem duplication in a child with Li-Fraumeni syndrome.

Li-Fraumeni syndrome (LFS) is one of the most common cancer predisposition syndromes that affects both children and adults. Individuals with LFS are at an increased risk of developing various types of cancer over their lifetime including soft tissue sarcomas, osteosarcomas, breast cancer, leukemia, brain tumors, and adrenocortical carcinoma. Heterozygous germline pathogenic variants in the tumor suppressor gene are the known causal genetic defect for LFS.

Unique Familial MLL(KMT2A)-Rearranged Precursor B-Cell Infant Acute Lymphoblastic Leukemia in Non-twin Siblings.

Background: Infant acute lymphoblastic leukemia (ALL) has never occurred in families except for the ∼100% concordant cases in monozygous twins attributed to twin-to-twin metastases. We report the first kindred with infant ALL in non-twin siblings. The siblings were diagnosed with MLL-rearranged (MLL-R) ALL 26 months apart.

Acquired isochromosome 12p, somatic TP53 and PTEN mutations, and a germline ATM variant in an adolescent male with concurrent acute megakaryoblastic leukemia and mediastinal germ cell tumor.

Previous reports have described an association between hematologic malignancies (HMs) and extragonadal germ cell tumor (GCT). Most patients have been adolescent males with mediastinal nonseminomatous GCT. Although a variety of HMs have been reported, there is a striking predilection toward acute megakaryoblastic leukemia (AMKL).

Implementation of high resolution single nucleotide polymorphism array analysis as a clinical test for patients with hematologic malignancies.

Single nucleotide polymorphism-based oligonucleotide arrays have been used as a research tool to detect genomic copy number changes and allelic imbalance in a variety of hematologic malignancies and solid tumors. The high resolution, genome-wide coverage, minimal DNA requirements, and relatively short turnaround time are advantageous for use in a clinical setting. We validated the Illumina HumanHap550 BeadChip array for clinical use by analyzing 127 pediatric leukemia and lymphoma samples that had previously been characterized by means of standard cytogenetic analysis and fluorescence in situ hybridization.