Constitutional 2p16.3 deletion including MSH6 and FBXO11 in a boy with developmental delay and diffuse large B-cell lymphoma.

We describe a case of a boy with neurodevelopmental delay and a diffuse large B-cell lymphoma (DLBCL) in whom we discovered a germline de novo 2p16.3 deletion including MSH6 and part of the FBXO11 gene. A causative role for MSH6 in cancer development was excluded based on tumor characteristics. The constitutional FBXO11 deletion explains the neurodevelopmental delay in the patient. The FBXO11 protein is involved in BCL-6 ubiquitination and BCL-6 is required for the germinal center reaction resulting in B cell differentiation. Somatic loss of function alterations of FBXO11 result in BCL-6 overexpression which is a known driver in DLBCL. We therefore consider that a causative relationship between the germline FBXO11 deletion and the development of DLBCL in this boy is conceivable.

Genomic profiling of Acute lymphoblastic leukemia in ataxia telangiectasia patients reveals tight link between ATM mutations and chromothripsis.

Recent developments in sequencing technologies led to the discovery of a novel form of genomic instability, termed chromothripsis. This catastrophic genomic event, involved in tumorigenesis, is characterized by tens to hundreds of simultaneously acquired locally clustered rearrangements on one chromosome. We hypothesized that leukemias developing in individuals with Ataxia Telangiectasia, who are born with two mutated copies of the ATM gene, an essential guardian of genome stability, would show a higher prevalence of chromothripsis due to the associated defect in DNA double-strand break repair. Using whole-genome sequencing, fluorescence in situ hybridization and RNA sequencing, we characterized the genomic landscape of Acute Lymphoblastic Leukemia (ALL) arising in patients with Ataxia Telangiectasia. We detected a high frequency of chromothriptic events in these tumors, specifically on acrocentric chromosomes, as compared with tumors from individuals with other types of DNA repair syndromes (27 cases total, 10 with Ataxia Telangiectasia). Our data suggest that the genomic landscape of Ataxia Telangiectasia ALL is clearly distinct from that of sporadic ALL. Mechanistically, short telomeres and compromised DNA damage response in cells of Ataxia Telangiectasia patients may be linked with frequent chromothripsis. Furthermore, we show that ATM loss is associated with increased chromothripsis prevalence in additional tumor entities.

Childhood neuroendocrine tumours: a descriptive study revealing clues for genetic predisposition.

BACKGROUND: Neuroendocrine tumours (NETs) are rare in children and limited data are available. We aimed to specify tumour and patient characteristics and to investigate the role of genetic predisposition in the aetiology of paediatric NETs. METHODS: Using the Dutch Pathology Registry PALGA, we collected patient- and tumour data of paediatric NETs in the Netherlands between 1991 and 2013 (N=483). RESULTS: The incidence of paediatric NETs in the Netherlands is 5.40 per one million per year. The majority of NETs were appendiceal tumours (N=441;91.3%). Additional surgery in appendiceal NETs was indicated in 89 patients, but performed in only 27 of these patients. Four out of five patients with pancreatic NETs were diagnosed with Von Hippel-Lindau disease (N=2) and Multiple Endocrine Neoplasia type 1 (N=2). In one patient with an appendiceal NET Familial Adenomatous Polyposis was diagnosed. On the basis of second primary tumours or other additional diagnoses, involvement of genetic predisposition was suggestive in several others. CONCLUSIONS: We identified a significant number of patients with a confirmed or suspected tumour predisposition syndrome and show that paediatric pancreatic NETs in particular are associated with genetic syndromes. In addition, we conclude that treatment guidelines for appendiceal paediatric NETs need revision and improved implementation.

Treatment of acute leukemia in children with ataxia telangiectasia (A-T).

Early onset ataxia telangiectasia (A-T) is a neurodegenerative DNA-instability disorder, which presents early in childhood. Hallmarks of A-T are progressive ataxia and a dramatic increased risk of developing malignancies (25%), especially of hematological origin. In children these malignancies mainly concern aggressive Non-Hodgkin lymphoma, acute leukemias and Hodgkin lymphoma. Of the acute leukemias, T-cell lymphoblastic leukemia (T-ALL) is by far the most common. Since patients with A-T experience increased toxicity to radio- and chemotherapeutic treatment, the optimal treatment strategy of acute leukemia remains subject of debate. Review of literature of treatment of T-ALL in patients with A-T (n = 18) showed that many patients are not diagnosed with A-T at time of presentation of T-ALL. This implicates that physicians must be aware of symptoms of A-T in young patients presenting with T-ALL. Complete remission rates are high following upfront modified as well as unmodified treatment strategies. Treatment of ALL in children with A-T is feasible and should be performed. Definitive treatment strategy must be determined by shared decision making with patient, caretakers and medical team. Future prospective studies are needed to elucidate optimal treatment strategy.

Adrenocortical carcinoma in children: first population-based clinicopathological study with long-term follow-up.

Adrenocortical carcinoma (ACC) is rare in both adult and pediatric populations. Literature suggests significant differences between children and adults in presentation, histological properties and outcome. The aim of this first nationwide study on pediatric ACC was to describe the incidence, presentation, pathological characteristics, treatment and survival in The Netherlands. All ACC patients aged <20 years at diagnosis and registered in the population-based Netherlands Cancer Registry between 1993 and 2010 were included. Clinical data were extracted from medical records. Archival histological slides were collected via the Dutch Pathology Registry (PALGA). We compared our findings to all clinical studies on pediatric ACC that were found on PubMed. Based on the results, 12 patients were identified: 8 females and 4 males. The median age was 4.1 years (range 1.1-18.6). The population-based age-standardized incidence rate for patients <20 years was 0.18 per million person-years. Autonomous hormonal secretion was present in 10 patients. Seven patients were aged ≤4 years at diagnosis, 5 presented with localized disease and 2 with locally advanced disease. Five patients were aged ≥5 years, 3 presented with distant metastases and 1 with locally advanced disease. For all patients, histological examination displayed malignant characteristics. All patients aged ≤4 years at diagnosis survived; the median follow-up was 97 months (57-179 months). All patients aged ≥5 years died; the median survival was 6 months (0-38 months). Pediatric ACC is extremely rare in the Western world. The clinical outcome was remarkably better in patients aged ≤4 years. This is in accordance with less advanced stage of disease at presentation, yet contrasts with the presence of adverse histological characteristics. Clinical management in advanced disease is adapted from adult practice in the absence of evidence regarding pediatric ACC.

Guidelines for surveillance of individuals with constitutional mismatch repair-deficiency proposed by the European Consortium "Care for CMMR-D" (C4CMMR-D).

Lynch syndrome (LS) is an autosomal dominant disorder caused by a defect in one of the DNA mismatch repair genes: MLH1, MSH2, MSH6 and PMS2. In the last 15 years, an increasing number of patients have been described with biallelic mismatch repair gene mutations causing a syndrome referred to as 'constitutional mismatch repair-deficiency' (CMMR-D). The spectrum of cancers observed in this syndrome differs from that found in LS, as about half develop brain tumours, around half develop digestive tract cancers and a third develop haematological malignancies. Brain tumours and haematological malignancies are mainly diagnosed in the first decade of life, and colorectal cancer (CRC) and small bowel cancer in the second and third decades of life. Surveillance for CRC in patients with LS is very effective. Therefore, an important question is whether surveillance for the most common CMMR-D-associated cancers will also be effective. Recently, a new European consortium was established with the aim of improving care for patients with CMMR-D. At a workshop of this group held in Paris in June 2013, one of the issues addressed was the development of surveillance guidelines. In 1968, criteria were proposed by WHO that should be met prior to the implementation of screening programmes. These criteria were used to assess surveillance in CMMR-D. The evaluation showed that surveillance for CRC is the only part of the programme that largely complies with the WHO criteria. The values of all other suggested screening protocols are unknown. In particular, it is questionable whether surveillance for haematological malignancies improves the already favourable outcome for patients with these tumours. Based on the available knowledge and the discussions at the workshop, the European consortium proposed a surveillance protocol. Prospective collection of all results of the surveillance is needed to evaluate the effectiveness of the programme.

High-quality care for all children with cancer.

BACKGROUND: Providing high-quality care for children with cancer could improve treatment outcomes, survival and quality of life of the children and parents. The aim of this study is to select high-quality care recommendations for all children with cancer based on literature and consensus for future development of quality indicators. MATERIALS AND METHODS: We performed an extensive search in databases for scientific literature and in websites of international health care and guideline development organizations to create an inventory of recommendations for the care for all children with cancer. The RAND modified Delphi method was used to grade and select recommendations for high-quality care. RESULTS: Our search resulted in a list of 131 recommendations on care for all children with cancer. The expert panel graded, discussed and prioritized these recommendations. Analysis of these ratings resulted ultimately in a list of 109 high-quality care recommendations for all children with cancer, including 31 prioritized recommendations. CONCLUSIONS: This study defines a set of high-quality care recommendations based on literature and consensus. These recommendations provide a basis for the development of a comprehensive set of quality indicators to evaluate care in paediatric oncology.

[Ovarian tumour in a girl with chronic abdominal pain and distension]. / Ovariumtumor bij een meisje met chronische buikpijn en zwelling van de buik.

A 12-year-old girl presented with chronic abdominal pain and distension that had persisted for 6 and 3 months, respectively. The cause was a Sertoli-Leydig cell tumour originating in the left ovary. The cyst and ovary were resected. The patient recovered and was asymptomatic 2 years after the operation. Ovarian tumours are rarely seen in children. The sex cordstromal tumours constitute a heterogeneous subgroup. Two of the most frequently observed sex cord-stromal tumours are the juvenile granulosa cell tumour and the Sertoli-Leydig cell tumour. Even though these tumours may contain histologically malignant characteristics, their behaviour is usually benign. Clinical characteristics are endocrine symptoms, fatigue, chronic abdominal pain and abdominal distension. In addition, pressure from the tumour mass may result in symptoms in adjacent organ systems. Surgical excision is usually curative. Patients with advanced disease may benefit from adjuvant chemotherapy. Chronic abdominal pain is frequently observed in children and, in some rare cases, may be caused by ovarian tumours.

Fumarase deficiency presenting with periventricular cysts.

A fumarase-deficient patient expressed a novel phenotype of congenital cerebral ventricular dilatation and periventricular cysts. The patient was a compound heterozygote for two mutations that are the only ones among the 12 published mutations that have been found in multiple, unrelated, fumarase-deficient patients.

The nuclear-encoded human NADH:ubiquinone oxidoreductase NDUFA8 subunit: cDNA cloning, chromosomal localization, tissue distribution, and mutation detection in complex-I-deficient patients.

We report the cloning of the cDNA sequence of the nuclear-encoded NDUFA8 subunit of NADH: ubiquinone oxidoreductase, the first mitochondrial respiratory chain complex. The NDUFA8 open reading frame (ORF) includes 519 bp and encodes 172 amino acids (Mr=20.1 kDa). The human cDNA sequence shows 86.2% identity with the bovine sequence, whereas the human NDUFA8 amino acid sequence is 87.8% similar to its bovine PGIV protein counterpart. Both human and bovine NDUFA8 contain a conserved cysteine motif. Polymerase chain reaction analysis of rodent/human somatic cell hybrids maps the human NDUFA8 gene to chromosome 9. A multiple tissue blot has revealed the highest NDUFA8 mRNA expression in human heart, skeletal muscle, and fetal heart. Mutation analysis of the NDUFA8 fibroblast cDNA in 20 patients with an isolated enzymatic complex I deficiency in cultured skin fibroblasts has revealed two polymorphisms, one within the ORF and the other in the 3' untranslated region of the NDUFA8 cDNA sequence. The allelic frequency of both polymorphisms was similar in controls and complex-I-deficient patients.

cDNA sequence and chromosomal localization of the remaining three human nuclear encoded iron sulphur protein (IP) subunits of complex I: the human IP fraction is completed.

NADH:ubiquinone oxidoreductase (complex I) of the mitochondrial respiratory chain can be fragmented in a flavoprotein (FP), iron-sulfur protein (IP), and hydrophobic protein (HP) subfraction. The IP subfraction is hypothesized to be significant, since it contains important prosthetic groups highly conserved among species. We cloned the cDNA of three remaining human NADH:ubiquinone oxidoreductase subunits of this IP fraction: the NDUFS2 (49 kDa), NDUFS3 (30 kDa), and NDUFS6 (13 kDa) subunits. All presented cDNAs include the complete open reading frame (ORF), which consist of 1392, 795, and 375 base pairs, coding for 463, 264, and 124 amino acids, respectively. The latter show 96, 90, and 83% homology with the corresponding bovine translation products. The 3' untranslated regions (UTR) are complete in all three cDNAs. Polymerase chain reaction performed with DNA isolated from somatic human-rodent cell hybrids containing defined human chromosomes as template gave a human-specific signal which mapped the NDUFS2 and NDUFS3 subunits to chromosomes 1 and 11, respectively. In the case of the NDUFS6 subunit a pseudogene may be present since signals were seen in the lanes containing chromosomes 5 and 6. The NDUFS2 contains a highly conserved protein kinase C phosphorylation site and the NDUFS3 subunit contains a highly conserved casein kinase II phosphorylation site which make them strong candidates for future mutation detection studies in enzymatic complex I-deficient patients.