Pediatric oncology clinical trial participation where the geography is vast: Development of a clinical research system for tertiary and satellite centers in Ontario, Canada.

Opportunities for participation in clinical trials are a core component of the care of children with cancer. In Ontario, many pediatric patients live long distances from their cancer center. This paper describes the work that was done in order to allow patients participating in Children's Oncology Group trials to receive care, including research protocol related care, jointly between the tertiary pediatric cancer center and the closer-to-home satellite center. The system is a pragmatic risk-based model, supporting excellence in care while ensuring good conduct of the research in compliance with applicable regulations and guidelines, including ethics oversight.

Anti-Müllerian Hormone in Female Adolescent Cancer Patients Before, During, and After Completion of Therapy: A Pilot Feasibility Study.

STUDY OBJECTIVE: Alkylating agents are implicated in premature ovarian insufficiency. To optimize counseling regarding future ovarian function in survivors of adolescent cancer, we describe anti-Müllerian hormone (AMH) levels in female adolescents at diagnosis, during, and shortly after completion of chemotherapy. DESIGN, SETTING, PARTICIPANTS, INTERVENTIONS, AND MAIN OUTCOME MEASURES: This was a prospective single-institution study. Participants were a mixed population of newly diagnosed postmenarchal female adolescents with malignancy. AMH was performed at diagnosis (T1), 6 months from diagnosis (T2), at end of therapy or 12 months [T3, whichever came first], 1 year after the end of therapy or 24 months from diagnosis [T4, whichever came first], and 18 months from the time of diagnosis (T5). All patients had baseline pelvic ultrasound examinations. Presence of menses and hot flashes were recorded at each time point. RESULTS: Sixteen participants with a median age at diagnosis of 14.3 years (range 12-17 years) were followed for 18.2 months (range, 14-24 months). Oncology diagnoses included leukemia, lymphoma, and sarcoma. Ten patients (62.5%) received alkylating agents with a median cumulative dose of 3041 mg/m2 (range, 2639-6478 mg/m2) of cyclophosphamide. Almost half (n = 7; 44%) experienced amenorrhea during treatment with resumption of menses in 6 of 7 patients (85%). Fifteen of 16 (94%) participants showed a decline in mean AMH levels by 6 months (T2) from diagnosis (15.8 IU/mL at T1 vs 6.5 IU/mL at T2; P = .003) and 12 of 15 (80%) showed at least some recovery of AMH (mean AMH at T4 = 13.2 IU/mL compared with 6.5 IU/mL at T2; P = .02). There was no difference in the mean decline nor recovery of AMH in those who did, vs did not receive cyclophosphamide. CONCLUSION: To our knowledge, this is the largest series to date in adolescents showing that AMH is uniformly suppressed during cancer therapy and short-term recovery occurs in just more than half of the patients by 18-24 months. The contribution of short-term AMH measurements in predicting long-term ovarian function remains to be defined. Long-term follow-up with serial AMH levels is required to help predict those at risk for premature ovarian insufficiency.

Mutational analysis of SDCCAG8 in Bardet-Biedl syndrome patients with renal involvement and absent polydactyly.

PURPOSE: To assess for SDCCAG8 mutations in Bardet-Biedl syndrome (BBS) subjects with renal involvement and no polydactyly, and to describe phenotypic characteristics of SDCCAG8-related disease. MATERIAL AND METHODS: Five patients (from 4 pedigrees) with clinical diagnosis of BBS, who had retinal and renal involvement and no polydactyly, were assessed. Sequence analysis of SDCCAG8 was undertaken and a detailed clinical review of an affected sibship was performed. RESULTS: A sibship of East Indian origin who carried a putative clinical diagnosis of BBS had compound heterozygous mutations in SDCCAG8 (p.Thr482LysfsX12/p.Asp543AlafsX24). The renal involvement was early and required transplant in both cases. Both were short statured and had asthma since childhood. The younger sister also had non-alcoholic fatty liver disease. Visual acuity and central fields were preserved in the teenage years in both patients. The optical coherence tomography showed preservation of the retinal lamination at the fovea; fundus autofluorescence demonstrated a perifoveal ring of hyperfluorescence as commonly observed in other forms of retinitis pigmentosa. Full-field electroretinogram revealed rod function to be more severely affected than cone function in both cases. CONCLUSION: Our results and prior literature suggest that SDCCAG8 could play an important role in presumed BBS patients affected with severe kidney disease and absent polydactyly. This report enhances the phenotypic description of SDCCAG8-related disease.

BBS mutational analysis: a strategic approach.

BACKGROUND: Bardet-Biedl syndrome (BBS, OMIM 209900) is a rare autosomal recessive, clinically and genetically heterogeneous disorder with 15 genes identified. The large amount of coding sequence challenges the cost effectiveness of mutational analysis of BBS. MATERIAL AND METHODS: We present our mutational analysis experience (83 BBS families) in the context of the literature published up to September 2010, to provide a comprehensive tabulation of all BBS1-BBS12 mutant alleles and optimize a screening approach. RESULTS: We identified two BBS disease alleles in 76% of probands. Together BBS1, BBS2, BBS10 and BBS12 account for 82.4% of published unrelated alleles. On average 82% of published alleles are private. The 267 published principal mutations were positioned and analysis of their distribution allowed the design of a mutation screening strategy. Starting by screening for recurrent mutations, for example BBS1 M390R (10% of our cohort) and BBS10 C91LfsX5 (6% of our cohort), allowed a capture of 23.5% of the principal mutated alleles. Following a hierarchy of frequently involved exons, subsequent sequencing of the 4 most commonly involved genes, BBS1, BBS10, BBS2 and BBS12 could bring this mutation detection to at least 62%. The 16 most frequently recurring alleles could be identified with the use of simple screening methods such as restriction enzyme digest and ARMS assay and require sequencing in only a few instances. CONCLUSION: Our results suggest that mutational analysis of such a "rare" genetically heterogeneous condition benefits from pooling of data. This allows the development of efficient and cost-conscious screening mutational analysis strategies.

BBS genotype-phenotype assessment of a multiethnic patient cohort calls for a revision of the disease definition.

Bardet-Biedl syndrome (BBS) is a ciliopathy characterized by retinal degeneration, obesity, polydactyly, renal abnormalities, and cognitive impairment for which 15 causative genes have been identified. Here we present the results of a mutational analysis of our multiethnic cohort of 83 families (105 cases); 75.9% of them have their mutations identified including 26 novel changes. Comprehensive phenotyping of these patients demonstrate that the spectrum of clinical features is greater than expected and overlapped with the features of other ciliopathies; specifically Alström and McKusick-Kauffman syndromes.

Mutations in chaperonin-like BBS genes are a major contributor to disease development in a multiethnic Bardet-Biedl syndrome patient population.

BACKGROUND: Bardet-Biedl syndrome is a pleiotropic disorder with 14 BBS genes identified. BBS1, BBS2, BBS4, BBS5, BBS7, BBS8, and BBS9 form a complex called the BBSome, which is believed to recruit Rab8(GTP) to the primary cilium and promote ciliogenesis. The second group, the chaperonin-like proteins BBS6, BBS10, and BBS12, have been defined as a vertebrate-specific branch of the type II chaperonin superfamily. These may play a role in the regulation of BBSome assembly. METHODS AND RESULTS: Using sequence analysis, the role of BBS6, 10 and 12 was assessed in the patient population comprising 93 cases from 74 families. Systemic and ocular phenotypes were defined. In the study, chaperonin-like BBS gene mutations accounted for the disease in approximately 36.5% of BBS families. A total of 38 different non-polymorphic exonic sequence variants were identified in 40.5% of BBS families (41.9% cases), of which 26 were novel (68%). Six cases had mutations present in more than one chaperonin-like BBS gene. One case with four mutations in BBS10 had a phenotype of overall greater severity. The phenotypes observed were beyond the classic BBS phenotype as they overlapped with characteristics of MKKS (congenital heart defect, vaginal atresia, hydrometrocolpos, cryptorchidism), as well as Alström syndrome (diabetes, hearing loss, liver abnormalities, endocrine anomalies, cardiomyopathy). CONCLUSIONS: While overlap between the MKKS and BBS phenotypes has previously been reported for cases with BBS6 mutations, we also observed MKKS phenotypes involving BBS10 and BBS12 and Alström-like phenotypes associated with mutations in BBS1, BBS2, BBS6, BBS7, BBS9, BBS10 and BBS12 for the first time.

NLRP7 mutations in women with diploid androgenetic and triploid moles: a proposed mechanism for mole formation.

Hydatidiform mole is an aberrant pregnancy with abnormal embryonic development and hydropic placental villi. Common moles are sporadic, not recurrent and affect one in every 1500 pregnancies in Western societies. Approximately, half of common moles are complete and mostly diploid androgenetic, whereas the remaining are partial and mostly triploid diandric. NLRP7 has been found to be responsible for a recurrent form of molar pregnancies. Recently, we showed that patients with NLRP7 mutations have an impaired inflammatory response to various stimuli. To date, molar tissues analyzed from patients with NLRP7 mutations have been found to be diploid and biparental. In this study, we report 10 new non-synonymous variants and one stop codon found in patients and not in controls. We demonstrate the presence of different types of moles, diploid biparental, diploid androgenetic, triploid and tetraploid conceptions, in patients with NLRP7 variants. We document in vitro and in vivo early embryo cleavage abnormalities in three patients. We propose a two-hit mechanism at the origin of androgenetic moles. This mechanism consists of variable degrees of early embryo cleavage abnormalities leading to chaotic mosaic aneuploidies, with haploid, diploid, triploid and tetraploid blastomeres. Surviving embryonic cells that reach implantation are then subject to the maternal immune response. Because of the patients' impaired inflammatory response, androgenetic cells, which are complete allograft, are able to grow and proliferate. In women with normal immune system, chaotic mosaic aneuploidies may also occur during early cleavage, however, androgenetic cells would die after implantation or stay undetected, confined to a small portion of the placenta.

Women heterozygous for NALP7/NLRP7 mutations are at risk for reproductive wastage: report of two novel mutations.

Familial recurrent hydatidiform moles are a rare recessive condition in which molar tissues have biparental contribution to their genome. One maternal locus responsible for this condition has been mapped to 19q13.4 and the causative gene, NALP7, identified (HUGO-approved nomenclature is now NLRP7). Here we report a first stop codon, c.295G>T (p.Glu99X) and a missense mutation, c.1970A>T (p.Asp657Val) in NLRP7 in two sisters with RHMs. We found these two mutations and a previously reported one, c.2078G>C (p.Arg693Pro) in a homozygous state, in males with normal reproductive outcomes. This suggests that NLRP7 is not required for normal spermatogenesis. The mother of the patients is heterozygous for Glu99X and had one stillbirth and three normal pregnancies. Our data on this new family and on heterozygous women from previously reported families indicate that women heterozygous for NLRP7 mutations are at risk for reproductive wastage without the manifestation of molar phenotype.