B-acute lymphoblastic leukemia and cystinuria in a patient with duplication 22q11.21 detected by chromosomal microarray analysis

Comprehensive clinical, genome and transcriptomic analysis of primary ghost cell odontogenic carcinoma

OBJECTIVES

There is currently no comprehensive genome-wide description of the primary ghost cell odontogenic carcinoma (GCOC), hindering our understanding of pathogenesis. We herein present a case with comprehensive clinical, genome and transcriptomic analysis. These will serve as the first comprehensive molecular atlas for primary GCOC. A 58-year-old male underwent subtotal resection with prosthetic restoration. Genome sequencing (WGS) detected previously identified CTNNB1 mutation with novel alterations of MAP3K, EP300, and 22q11.21 region. Transcriptome results showed significant involvement of cytokine-cytokine receptor interaction and PI3K-Akt signaling pathway. These results need to be compared with more GCOCs for more accurate clinical guidance.

Acute Pre-B Lymphoblastic Leukemia and Congenital Anomalies in a Child with a de Novo 22q11.1q11.22 Duplication

Microdeletions and microduplications are recurrent in the q11.2 region of chromosome 22. The 22q11.2 duplication syndrome is an extremely variable disorder with a phenotype ranging from severe intellectual disability, facial dysmorphism, heart defects, and urogenital abnormalities to very mild symptoms. Both benign and malignant hematological entities are rare. A male patient was diagnosed with mild facial dysmorphia, congenital heart anomalies shortly after birth and acute bowel obstruction due to malrotation of the intestine at the age of 3 years. A whole-genome single nucleotide polymorphism (SNP) array revealed a de novo 6.6 Mb duplication in the 22q11.1q11.22 chromosomal region. A year later, the patient was diagnosed with acute pre-B lymphoblastic leukemia (pre-B ALL). Five genes, CDC45, CLTCL1, DGCR2, GP1BB and SEPT5, in the 22q11.1q11.22 region are potentially responsible for cell cycle division. We hypothesized that dosage imbalance of genes implicated in the rearrangement could have disrupted the balance between cell growth and differentiation and played a role in the initiation of malignancy with a hyperdiploid leukemic clone, whereas over-expression of the TBX1 gene might have been responsible for congenital heart defects and mild facial dysmorphia.

22q11.2 microduplication syndrome and juvenile glaucoma

BACKGROUND

22q11.2 microduplication is a relatively recently recognized syndrome. Findings in affected individuals range from apparent normality to a wide variety of systemic and ocular conditions. We describe the association between 22q11.2 microduplication and juvenile glaucoma in two brothers.

MATERIALS AND METHODS

We reviewed ophthalmological, genetic, and hematological medical records of two patients and their unaffected mother.

RESULTS

A 2.07 Mb interstitial duplication in 22q11.21 and a smaller 182 kb duplication in 22q11.23 were identified in both subjects. Patient 1 showed an initial intraocular pressure (IOP) of 15 mmHg in right eye (RE) and 32 mmHg in left eye (LE) under maximum medical treatment. Deep sclerectomy surgery in LE was converted to trabeculectomy due to a macroperforation of the trabeculo-descemetic membrane. Postoperatively, the patient developed persistent hypotony with retinal folds, while IOP in RE increased to 28 mmHg. Trabeculectomy in RE was also complicated by persistent hypotony. Autologous blood injection was performed, resulting in an increase in both visual acuity and IOP. Patient 2 presented with an IOP of 29 mmHg in RE and 33 mmHg in LE. We planned an elective trabeculectomy and added orally administered acetazolamide. The patient developed bilinear cytopenia that contraindicated the surgical procedure. After hematologic normalization, the patient underwent trabeculectomy in LE, causing persistent hypotony. We performed deep sclerectomy surgery in RE, without any significant intra- or post-operative complications.

CONCLUSIONS

22q11.2 microduplication syndrome can be associated with juvenile glaucoma. Trabeculectomy may be complicated by persistent hypotony. Deep sclerectomy appears to be a better surgical option, although the presence of a thin sclera may result in conversion to trabeculectomy.

Preexisting conditions in pediatric ALL patients: Spectrum, frequency and clinical impact

INTRODUCTION

The etiology of acute lymphoblastic leukemia remains undisclosed in the majority of cases. A number of rare syndromic conditions are known to predispose to different forms of childhood cancer including ALL. The present study characterized the spectrum and clinical impact of preexisting diseases in a cohort of ALL patients from Germany, Austria and Switzerland with a focus on genetic diseases predisposing to cancer development.

METHODS

Retrospective database and study chart review included all patients from Germany, Austria and Switzerland (n = 4939) enrolled into multicenter clinical trial AIEOP-BFM ALL 2000 between July 1999 and June 2009. Patients enrolled into study AIEOP-BFM ALL 2009 - which was initiated subsequent to AIEP-BFM ALL 2000 - who were reported with a cancer prone syndrome or chromosomal abnormality were additionally included in this study to increase conclusiveness of observations.

RESULTS

A total of 233 patients with at least one reported condition could be identified. The following conditions were reported in more than one patient: Gilbert's disease (n = 13), neurofibromatosis type I (n = 8), ataxia telangiectasia (n = 8), thalassemia (n = 7), Nijmegen Breakage syndrome (n = 6), cystic fibrosis (n = 4), glucose-6-phosphate dehydrogenase deficiency (n = 4), Noonan syndrome (n = 2), Klinefelter syndrome (n = 2), alpha-1-antitrypsin deficiency (n = 2), primary ciliary dyskinesia (n = 2). Especially those syndromes with a known cancer predisposition (NF type I, Ataxia telangiectasia, Nijmegen Breakage syndrome etc.) were associated with certain general and ALL-related characteristics, high therapy-related toxicity and reduced survival.

CONCLUSION

The spectrum of underlying diseases within ALL patients is dispersed. A small number of ALL patients are reported with cancer predisposition syndromes at initial diagnosis which are associated with high rates of therapy-related toxicity and a markedly reduced chance of survival. The true prevalence of these conditions within the ALL population remains unknown due to inapparent clinical presentation. A targeted clinical and/or genetic examination for certain diagnoses like NF type I, Ataxia telangiectasia or Nijmegen Breakage syndrome could identify patients who benefit from adjustment of antileukemic therapy or intensification of supportive care.

Significant evidence of linkage for a gene predisposing to colorectal cancer and multiple primary cancers on 22q11

Objectives:

The genetic basis of colorectal cancer (CRC) is not completely specified. Part of the difficulty in mapping predisposition genes for CRC may be because of phenotypic heterogeneity. Using data from a population genealogy of Utah record linked to a statewide cancer registry, we identified a subset of CRC cases that exhibited familial clustering in excess of that expected for all CRC cases in general, which may represent a genetically homogeneous subset of CRC.

Methods:

Using a new familial aggregation method referred to as the subset genealogic index of familiality (subsetGIF), combined with detailed information from a statewide tumor registry, we identified a subset of CRC cases that exhibited excess familial clustering above that expected for CRC: CRC cases who had at least one other primary tumor at a different site. A genome-wide linkage analysis was performed on a set of high-risk CRC pedigrees that included multiple CRC cases with additional primaries to identify evidence for predisposition loci.

Results:

A total of 13 high-risk CRC pedigrees with multiple CRC cases with other primary cancers were identified. Linkage analysis identified one pedigree with a significant linkage signal at 22q11 (LOD (logarithm (base 10) of odds)=3.39).

Conclusions:

A predisposition gene or variant for CRC that also predisposes to other primary cancers likely resides on chromosome 22q11. The ability to use statewide population genealogy and tumor registry data was critical to identify an informative subset of CRC cases that is possibly more genetically homogeneous than CRC in general, and may have improved statistical power for predisposition locus identification in this study.

Dissecting the genotype in syndromic intellectual disability using whole exome sequencing in addition to genome-wide copy number analysis

When a known microimbalance affecting multiple genes is detected in a patient with syndromic intellectual disability, it is usually presumed causative for all observed features. Whole exome sequencing (WES) allows questioning this assumption. In this study of three families with children affected by unexplained syndromic intellectual disability, genome-wide copy number and subsequent analyses revealed a de novo maternal 1.1 Mb microdeletion in the 14q32 imprinted region causing a paternal UPD(14)-like phenotype, and two inherited 22q11.21 microduplications of 2.5 or 2.8 Mb. In patient 1 carrying the 14q32 microdeletion, tall stature and renal malformation were unexplained by paternal UPD(14), and there was no altered DLK1 expression or unexpected methylation status. By WES and filtering with a mining tool, a novel FBN1 missense variant was found in patient 1 and his mother, who both showed clinical features of Marfan syndrome by thorough anthropometric assessment, and a novel EYA1 missense variant as a probable cause of the renal malformation in the patient. In patient 2 with the 22q11.21 microduplication syndrome, skin hypo- and hyperpigmentation and two malignancies were only partially explained. By WES, compound heterozygous BLM stop founder mutations were detected causing Bloom syndrome. In male patient 3 carrying a 22q11.21 microduplication inherited from his unaffected father, WES identified a novel missense variant in the OPHN1 X-linked intellectual disability gene inherited from the unaffected mother as a possible additional cause for developmental delay. Thus, WES seems warranted in patients carrying microdeletions or microduplications, who have unexplained clinical features or microimbalances inherited from an unaffected parent.