Wilms Tumor With Raised Serum Alpha-Fetoprotein: Highlighting the Need for Novel Circulating Biomarkers.

Wilms tumor (WT) is the commonest cause of renal cancer in children. In Europe, a diagnosis is made for most cases on typical clinical and radiological findings, prior to pre-operative chemotherapy. Here, we describe a case of a young boy presenting with a large abdominal tumor, associated with raised serum alpha-fetoprotein (AFP) levels at diagnosis. Given the atypical features present, a biopsy was taken, and histology was consistent with WT, showing triphasic WT, with epithelial, stromal, and blastemal elements present, and positive WT1 and CD56 immunohistochemical staining. During pre-operative chemotherapy, serial serum AFP measurements showed further increases, despite a radiological response, before a subsequent fall to normal following nephrectomy. The resection specimen was comprised of ~55% and ~45% stromal and epithelial elements, respectively, with no anaplasia, but immunohistochemistry using AFP staining revealed positive mucinous intestinal epithelium, consistent with the serum AFP observations. The lack of correlation between tumor response and serum AFP levels in this case highlights a more general clinical unmet need to identify WT-specific circulating tumor markers.

11p15.5 epimutations in children with Wilms tumor and hepatoblastoma detected in peripheral blood.

BACKGROUND: Constitutional or somatic mosaic epimutations are increasingly recognized as a mechanism of gene dysregulation resulting in cancer susceptibility. Beckwith-Wiedemann syndrome is the cancer predisposition syndrome most commonly associated with epimutation and is extremely variable in its phenotypic presentation, which can include isolated tumors. Because to the authors' knowledge large-scale germline DNA sequencing studies have not included methylation analysis, the percentage of pediatric cancer predisposition that is due to epimutations is unknown. METHODS: Germline methylation testing at the 11p15.5 locus was performed in blood for 24 consecutive patients presenting with hepatoblastoma (3 patients) or Wilms tumor (21 patients). RESULTS: Six individuals with Wilms tumor and 1 patient with hepatoblastoma were found to have low-level gain of methylation at imprinting control 1, and a child with hepatoblastoma was found to have loss of methylation at imprinting control 2. The loss of methylation at imprinting control 2 was found to be maternally inherited, despite not being associated with any detectable genomic alteration. CONCLUSIONS: Overall, 33% of patients (8 of 24 patients) with Wilms tumor or hepatoblastoma were found to have an epigenetic susceptibility that was detectable in the blood. It is interesting to note that low-level gain of methylation at imprinting control 1 predominantly was detected in females with bilateral Wilms tumors. Further studies in larger cohorts are needed to determine the efficacy of testing all patients with Wilms tumor or hepatoblastoma for 11p15.5 epimutations in the blood as part of DNA analysis because this hallmark of predisposition will not be detected by sequencing-based approaches and detecting a cancer predisposition may modify treatment.

Screening and identification of non-inflammatory specific protein markers in Wilms' tumor tissues.

Wilms' tumor is one of the most common malignancies in children, and early diagnosis is critical for its subsequent treatment and prognosis. Our previous study employed proteomics to investigate protein markers in the serum of Wilms' tumor children. The present study aimed to identify specific protein markers in Wilms' tumor. Proteomic comparison of Wilms' tumor with normal kidney tissues and the sera of systemic inflammatory response syndrome (SIRS) controls was performed. Surface-enhanced laser desorption ionization time-of-flight (SELDI-TOF-MS) identified a protein with m/z 8350 as specific to Wilms' tumor. The target protein was purified using sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) and identified as profilin-1 by matrix-assisted laser desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF). Its expression was validated using real-time polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA). Our data identify profilin-1 as a potential protein marker for Wilms' tumor and demonstrate the feasibility of the above procedures for screening and identification of tumor-specific protein markers.

PAI-1 and protein C as early markers of veno-occlusive disease in patients treated for Wilms tumor.

BACKGROUND: Hepatic veno-occlusive (VOD) disease has been described in hematopoietic stem cell transplantation (HSCT), solid tumors, and acute lymphoblastic leukemia. The incidence of VOD in Wilms tumor (WT) ranges from 1.2% to 8%. The diagnosis of VOD is clinical, and there are no validated laboratory biomarkers. PROCEDURE: We prospectively evaluated the specificity and sensitivity of plasminogen-activator inhibitor-1 (PAI-1) and protein C as diagnostic markers of VOD in WT patients. Fifty patients treated from 2008 to 2016 for WT were eligible. VOD was diagnosed according to modified Seattle criteria and retrospectively reclassified according to the recently published criteria for VOD in pediatric HSCT patients. RESULTS: VOD occurred in 6 of 50 patients (12%) after 20 to 97 days from starting chemotherapy. The average duration of VOD was 10 days (range, 4-13 days). PAI-1 levels were elevated in all VOD patients, while a decrease in protein C levels was observed in 33% of patients with VOD. PAI-1 antigen (Ag) values ≥ 26.4 ng/mL demonstrated high sensitivity and specificity for the clinical diagnosis of VOD with sensitivity 100%, specificity 93%; whereas protein C levels below 34.5% had sensitivity 67%, specificity 100%. Both PAI-1 and protein C had an high negative predictive value: PAI-1 Ag 100%; protein C 95%. CONCLUSIONS: PAI-1 Ag and protein C have good sensitivity and specificity for the diagnosis of VOD in WT patients. Their high negative predictive value can be used in the differential diagnosis of liver toxicity, especially in VOD episodes with absent or delayed hyperbilirubinemia.

Preoperative diagnosis of clear cell sarcoma of the kidney by detection of BCOR internal tandem duplication in circulating tumor DNA.

Clear cell sarcoma of the kidney (CCSK) is the second most common renal malignancy in children. The prognosis is poorer in CCSK than in Wilms' tumor, and multimodal treatment including surgery, intensive chemotherapy, and radiation is required to improve the outcome for children with CCSK. Histological evaluation is required for the diagnosis. However, biopsies of tumors to obtain diagnostic specimens are not routinely performed because of the risk of spreading tumor cells during the procedure. Recently, internal tandem duplication (ITD) of BCOR has been recognized as a genetic hallmark of CCSK. We herein established a novel BCOR-ITD-specific polymerase chain reaction method with well-designed primers, and then performed a liquid biopsy for cell-free DNA (cfDNA) obtained from plasma of three children with nonmetastatic renal tumors (stage II) and from one control. BCOR-ITD was positively detected in the cfDNA of two cases, both of which were later diagnosed as CCSK based on histological feature of the resected tumor specimen, while it was not detected for a normal control and a patient diagnosed with Wilms' tumor. Our study is the first one of preoperative circulating tumor DNA assay in pediatric renal tumors. The liquid biopsy method enables less invasive, preoperative diagnosis of CCSK with no risk of tumor spillage, which can avoid iatrogenic upstaging.

Biomarkers for Wilms Tumor: A Systematic Review.

PURPOSE: Wilms tumor is the most common childhood renal malignancy and the fourth most common childhood cancer. Many biomarkers have been studied but there has been no comprehensive summary. We systematically reviewed the literature on biomarkers in Wilms tumor to quantify the prognostic implications of the presence of individual tumor markers. MATERIALS AND METHODS: We searched for English language studies from 1980 to 2015 performed in patients younger than 18 years with Wilms tumor and prognostic data. The protocol was conducted per PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Two reviewers abstracted data in duplicate using a standard evaluation form. We performed descriptive statistics, then calculated relative risks and 95% confidence intervals for markers appearing in multiple level II or III studies. RESULTS: A total of 40 studies were included examining 32 biomarkers in 7,381 patients with Wilms tumor. Studies had a median of 61 patients, 24 biomarker positive patients per series and a median followup of 68.4 months. Median percentages of patients with stages 1, 2, 3, 4 and 5 tumors were 28.5%, 26.4%, 24.5%, 14.1% and 1.7%, respectively, and 10.2% had anaplasia. The strongest negative prognostic association was loss of heterozygosity at 11p15, with a risk of recurrence of 5.00, although loss of heterozygosity at 1p and gain of function at 1q were also strongly linked to increased recurrence (2.93 and 2.86, respectively). CONCLUSIONS: Several tumor markers are associated with an increased risk of recurrence or a decreased risk of overall survival in patients with Wilms tumor. These data suggest targets for development of diagnostic tests and potential therapies.

Gonadal function in boys with newly diagnosed cancer before the start of treatment.

STUDY QUESTION: Are Inhibin B and testosterone levels reduced in boys with newly diagnosed cancer prior to therapy? SUMMARY ANSWER: Pretreatment serum levels of Inhibin B and testosterone are significantly reduced in boys with newly diagnosed cancer, compared to reference values. WHAT IS ALREADY KNOWN: Disease-related gonadal impairment has been demonstrated in girls and young women diagnosed with cancer, prior to therapy. STUDY DESIGN, SIZE, DURATION: We conducted a descriptive study in boys newly diagnosed with cancer between January 2006 and February 2014. PARTICIPANTS/MATERIALS, SETTING, METHODS: Serum Inhibin B and testosterone levels were determined in 224 boys, up to the age of 18 years, with newly diagnosed cancer prior to therapy. Hormone levels were compared with age-matched reference values. The cohort consisted of patients with acute lymphoblastic leukaemia (ALL), acute myeloid leukaemia (AML), Hodgkin lymphoma (HL), non-Hodgkin lym-phoma (NHL), nephroblastoma, neuroblastoma and sarcoma. MAIN RESULTS AND THE ROLE OF CHANCE: This study demonstrates reduced serum levels of Inhibin B in boys with newly diagnosed cancer, compared to reference values (standard deviation score (SDS) -0.9, P < 0.001). Median Inhibin B level in patients was 103.5 ng/l (range 20-422). Of all patients, 78.6% showed Inhibin B levels below the 50th percentile, and 58.5% had Inhibin B levels below the 25th percentile. Serum testosterone levels were significantly lower than the reference range population (SDS -1.2, P < 0.001). Median testosterone level in pubertal patients was 7.3 nmol/l (range 0.1-23.6). No correlation with clinical signs of general illness and hormone levels were observed. LIMITATIONS, REASONS FOR CAUTION: In this study, reproductive hormone levels were compared with age-matched reference values. Future studies may compare reproductive hormone levels with case controls. WIDER IMPLICATIONS OF THE FINDINGS: Future longitudinal studies are necessary to determine whether pretreatment impaired gonadal function at the time of cancer diagnosis is an important determinant of ultimate recovery of spermatogenesis after treatment and later on in adulthood. STUDY FUNDING/COMPETING INTERESTS: W.v.D. was supported by the Pediatric Oncology Center Society for Research (KOCR), Rotterdam, The Netherlands. A.-L.L.F.v.d.K. was supported by EU FP7 PanCare LIFE study. The authors have no conflicts of interest.

ß-HCG Elevation in Wilms Tumor: An Uncommon Presentation.

Wilms tumor (nephroblastoma) is a readily diagnosed common abdominal tumor in children. Rarely, it may present with factors that may confound the diagnosis. We report a 6-year-old female child who presented with a rapidly growing and invasive abdominal mass with the histopathologic features of Wilms tumor associated with an elevated serum beta human chorionic gonadotropin, which has not been previously reported in this condition.

Circulating serum miRNAs as potential biomarkers for nephroblastoma.

BACKGROUND: Nephroblastoma (or Wilms tumor-WT) is the most common childhood kidney cancer. In Europe, nephroblastoma is treated with preoperative chemotherapy without histological confirmation by biopsy. Therefore, minimal-invasive diagnostic markers confirming nephroblastoma diagnosis are highly warranted. PROCEDURE: In our study, we aim to identify circulating miRNAs with diagnostic potential for differentiating nephroblastoma from controls. We determined the level of 19 miRNAs in serum of 32 patients with nephroblastoma and 12 controls with quantitative real-time PCR. Three miRNAs were further tested in an independent validation set including sera of patients with renal tumors other than Wilms. RESULTS: In total, 14 miRNAs showed significantly higher abundance in serum of patients with nephroblastoma than in controls. The miRNAs with highest diagnostic potentials included miRs-130b-3p, -100-5p, and -143-3p with an AUC of 0.94, 0.90, and 0.89, respectively. A signature based on these three miRNAs to differentiated patients from controls with an accuracy of 84.58%, a sensitivity of 76.67%, and a specificity of 92.5%. Higher expression of miRs-100-5p and -130b-3p was confirmed in an independent validation set. The signature based on miRs-100-5p and -130b-3p differentiated patients with nephroblastoma from healthy controls with an accuracy, sensitivity, and specificity of 79.6%, 69.2%, and 90.0%, respectively. CONCLUSION: In summary, we provide first evidence that serum miR-100-5p and -130b-3p hold potential as biomarker for WT irrespective of the subtype and that expression level of these miRNA in serum is unaffected by differences in serum collection.

A Phase I Study of the Anti-Idiotype Vaccine Racotumomab in Neuroblastoma and Other Pediatric Refractory Malignancies.

BACKGROUND: Pediatric neuroectodermal malignancies express N-glycolylated gangliosides including N-glycolyl GM3 (NeuGcGM3) as targets for immunotherapy. PROCEDURE: We evaluated the toxicity and maximum tolerated dose and immunological response of racotumomab, an anti-idiotype vaccine targeting NeuGcGM3 through a Phase I study enrolling children with relapsed or resistant tumors expressing NeuGcGM3. MATERIALS AND METHODS: Drug dose was escalated to three levels (0.15-0.25-0.4 mg) of racotumomab administered intradermally. Each drug level included three patients receiving a total of three doses, every 14 days. A confirmation cohort was added to the highest dose level. Antibody response was assessed upon study entry and at 4-week intervals for at least three immunological determinations for each patient. RESULTS: Fourteen patients were enrolled (10 with neuroblastoma, one with retinoblastoma, one with Wilms' tumor, and two with brainstem glioma). Three patients completed the three drug levels and three were enrolled in the confirmation cohort. One patient died of tumor progression before completing the three applications. Racotumomab was well tolerated. The only side effect observed was grade 1-2 toxicity at the injection site. Racotumomab elicited an IgM and/or IgG antibody response directed against NGcGM3 in nine patients and IgM against racotumomab in 11 of 13 evaluable patients. The maximum tolerated dose was not reached and no dose-limiting toxicity was seen. CONCLUSIONS: Racotumomab vaccination has a favorable toxicity profile up to a dose of 0.4 mg, and most patients elicited an immune response. Its activity as immunotherapy for neuroectodermal malignancies will be tested in further clinical trials.

Phase 2 trial of sorafenib in children and young adults with refractory solid tumors: A report from the Children's Oncology Group.

BACKGROUND: Sorafenib is an oral small molecule inhibitor of multiple kinases controlling tumor growth and angiogenesis. The purpose of the phase 2 study was to determine the response rate of sorafenib and gain further information on the associated toxicities, pharmacokinetics, and pharmacodynamics of sorafenib in children and young adults with relapsed or refractory tumors including rhabdomyosarcoma, Wilms tumor, hepatocellular carcinoma (HCC), and papillary thyroid carcinoma (PTC). PROCEDURE: Sorafenib, 200 mg/m(2) /dose, was administered every 12 hr continuously for 28 day cycles using a two-stage design in two primary strata (rhabdomyosarcoma and Wilms tumor) and two secondary strata (HCC and PTC). Correlative studies in consenting patients included determination of sorafenib steady state trough concentrations and assessments of VEGF and sVEGFR2. RESULTS: Twenty patients (median age of 11 years; range, 5-21) enrolled. No objective responses (RECIST) were observed in the 10 evaluable patients enrolled in each of the two primary disease strata of rhabdomyosarcoma and Wilms tumor. No patients with HCC or PTC were enrolled. Sorafenib was not associated with an excessive rate of dose-limiting toxicity (DLT). The mean ± SD steady state concentration during cycle 1 day 15 was 6.5 ± 3.9 µg/ml (n = 10). CONCLUSIONS: Sorafenib was well tolerated in children at 200 mg/m(2) /dose twice daily on a continuous regimen with toxicity profile and steady state drug concentrations similar to those previously reported. Single agent sorafenib was inactive in children with recurrent or refractory rhabdomyosarcoma or Wilms tumor.

[Expression and promoter methylation of SIX2 gene in peripheral blood of pediatric patients with nephroblastoma].

OBJECTIVE: To explore the transcriptional expression and promoter methylation status of SIX2 gene in peripheral blood of pediatric children with nephroblastoma and discuss their clinicopathological correlations. METHODS: Approved by the hospital ethics committee, peripheral blood samples were collected from 45 children with Wilms' tumor(case group) at the Department of Pediatric Surgery, First Affiliated Hospital, Zhengzhou University from October 2008 to January 2012. And another 15 pediatric cases gender-and-age matched, were selected as the control group (excluding cancer and other malignant diseases). The real-time quantitative (qRT)-PCR and methylation-specific PCR (MSP) were used to detect the mRNA expression level and methylation status of SIX2 gene.t or χ(2) test were used. Then analyzed their clinicopathological correlations in the case group and how SIX2 gene methylation affected its transcription. RESULTS: Relative quantity(RQ) of SIX2 mRNA in the case group was higher than that of the control group (1.93 ± 1.10 vs 0.57 ± 0.39, t = 5.354, P = 0.000). There were 8 SIX2 gene methylation-positive cases in the case group versus 12 cases in the control group. And the methylation positive ratio was extremely lower in the case group (χ(2) = 19.600, P = 0.000). RQ values in the case group was associated with tumor size, clinical stage, pathological type, lymph node metastasis, treatment and outcome (all P < 0.05). RQ values in the methylated group was lower than that of the unmethylated group both in case and control group (1.35 ± 0.44 vs 1.95 ± 1.15, 0.43 ± 0.29 vs 1.13 ± 0.20, t = 2.459 and 3.896, P = 0.020 and 0.002) . RQ values of case group was higher than that of the control group in methylated group (t = 5.624, P = 0.000) . No statistical significance existed in RQ values between the case and control groups of unmethylated group (t = 1.222, P = 0.229) . CONCLUSIONS: A close correlation between SIX2 low methylation and high mRNA expression in blood suggests that aberrant promoter methylation is possibly one of gene expression regulations, and may be correlated with the occurrence and development of Wilms' tumor. And SIX2 gene in methylated Wilms' tumor may play the role of oncogenes. A negative correlation exists between the overexpression in transcriptional level and its methylation status.

Treatment-independent miRNA signature in blood of Wilms tumor patients.

BACKGROUND: Blood-born miRNA signatures have recently been reported for various tumor diseases. Here, we compared the miRNA signature in Wilms tumor patients prior and after preoperative chemotherapy according to SIOP protocol 2001. RESULTS: We did not find a significant difference between miRNA signature of both groups. However both, Wilms tumor patients prior and after chemotherapy showed a miRNA signature different from healthy controls. The signature of Wilms tumor patients prior to chemotherapy showed an accuracy of 97.5% and of patients after chemotherapy an accuracy of 97.0%, each as compared to healthy controls. CONCLUSION: Our results provide evidence for a blood-born Wilms tumor miRNA signature largely independent of four weeks preoperative chemotherapy treatment.

Multicenter study identified molecular blood-born protein signatures for Wilms Tumor.

Wilms Tumor (WT) is the most common renal childhood tumor. Recently, we reported a cDNA microarray expression pattern that varied between WTs with different risk histology. Since the Societé Internationale d'Oncologie Pédiatrique (SIOP) in Europe initiates treatment without a histological confirmation, it is important to identify blood-born markers that indicate WT development. In a multicenter study, we established an autoantibody signature by using an array with 1,827 recombinant E. coli clones. This array was screened with sera of patients with WT recruited by SIOP or the Children's Oncology Group (COG). We report an extended number of antigens that are reactive with autoantibodies present in sera from patients with WT. We established an autoantibody signature that separates untreated patients with WT recruited in SIOP from non-WT controls with a specificity of 0.83 and a sensitivity of 0.82 at standard deviations of 0.02 and 0.04, respectively. Likewise, patients recruited in the COG in the United States were separated from the controls with an accuracy of 0.83 at a standard deviation of 0.02. Proteins that were most significant include zinc finger proteins (e.g., ZFP 346), ribosomal proteins and the protein fascin that has been associated with various types of cancer including renal cell carcinoma. Our study provides first evidence for autoantibody signatures for WTs and suggests that these may be most informative before chemotherapy. We present the first multicenter study of autoantibody signatures in patients with WT. We established an autoantibody signature that separates patients with WT from controls.

Vitamin D status in pediatric patients with a history of malignancy.

BACKGROUND: Multiple studies associate low vitamin D levels with cancer morbidity and mortality. However, few studies have measured vitamin D in pediatric patients with malignancy. Our aim was to assess vitamin D status in a large cohort of pediatric patients with cancer and to define risk factors for deficiency. METHODS: Circulating 25-hydroxyvitamin D (25OHD) levels were measured in 211 patients. Calcium intake and sun exposure habits were assessed in 142 patients (age 12.1 ± 5.8 y; number of male patients, 69; mean time from diagnosis, 4.4 ± 3.8 y). RESULTS: Daily calcium intake was 66.2 ± 39.3% of the recommended daily allowance. Mean 25OHD levels were 20.6 ± 7.9 ng/ml. Vitamin D deficiency (<15 ng/ml) was found in 24.6% of the patients and insufficiency (15-20 ng/ml) in 23.2%. Younger age and amount of sun exposure were associated with higher serum 25OHD. No association was found with calcium intake, disease type, gender, BMI SD score, years since diagnosis, or stem cell transplantation. The 25OHD levels during winter were significantly lower than the summer levels. CONCLUSION: The prevalence of vitamin D deficiency and insufficiency in pediatric patients with a history of malignancy was high, whereas calcium intake was low. These findings are concerning, given the risk for osteoporosis in this population and the possible role of vitamin D in the context of malignancy.

Identification of potential serum biomarkers for Wilms tumor after excluding confounding effects of common systemic inflammatory factors.

Wilms tumor is the most common pediatric tumor of the kidney. Previous studies have identified several serum biomarkers for Wilms tumor; however, they lack sufficient specificity and may not adequately distinguish Wilms tumor from confounding conditions. To date, no specific protein biomarker has been confirmed for this pediatric tumor. To identify novel serum biomarkers for Wilms tumor, we used proteomic technologies to perform protein profiling of serum samples from pre-surgery and post-surgery patients with Wilms tumor and healthy controls. Some common systemic inflammatory factors were included to control for systemic inflammation. By comparing protein peaks among the three groups of sera, we identified two peaks (11,526 and 4,756 Da) showing significant differential expression not only between pre-surgery and control sera but also between pre-surgery and post-surgery sera. These two peaks were identified as serum amyloid A1 (SAA1) and apolipoprotein C-III (APO C-III). Western blot analysis confirmed that both proteins were expressed at higher levels in pre-surgery sera than in post-surgery and control sera. Using the method of leave-1-out for cross detection, we demonstrate that detection of these two candidate biomarkers had high sensitivity and specificity in discriminating pre-surgery sera from post-surgery and normal control sera. Taken together, these findings suggest that SAA1 and APO C-III are two potential biomarkers for Wilms tumor.

Identification of novel serum biomarkers in child nephroblastoma using proteomics technology.

To screen and identify serum biomarkers for nephroblastoma in children using surface-enhanced laser desorption/ionization (SELDI) and other proteomics technologies. The surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS) was used to identify biomarkers in 100 children with nephroblastoma and 30 gender and age-matched normal healthy children. There were 30 cases of pre-operative patients and 70 cases of post-operative patients. Differentially expressed serum proteins were screened. The target proteins were then separated, purified, and analyzed by multidimensional high performance liquid chromatography (HPLC). The peptide mass fingerprints (PMFs) of each protein were obtained after scanning with LC-MS/MS (LTQ). The proteins were identified using SEQUEST and the biological functions and characterizations of these proteins were analyzed with bioinformatic methods. Two differential proteins (m/z 6455.5, 9190.8) were obtained. According to SEQUEST, the molecular masses of this two proteins indicated that they were apolipoprotein C-I and haptoglobin, respectively. Expressions of the two proteins were lower in the pre-surgery group compared with the post-surgery and control group (P<0.01). In contrast, the expression of this two proteins were higher in the early stage than in the advanced stage of nephroblastoma. Apolipoprotein C-I and haptoglobin may be used as potential biomarkers to predict the degree of malignancy, therapeutic outcomes, and prognosis of nephroblastoma in children.

Is the NBN gene mutation I171V a potential risk factor for malignant solid tumors in children?

NBN gene is considered as one of the low-to-moderate cancer susceptibility gene. At least 4 germline NBN mutations have been found in several malignancies in adults. In our studies, we observed the high incidence of germline mutation I171V of NBN gene in breast, colorectal, larynx cancer, and in multiple primary tumors. In this study, we would like to answer the question whether I171V germline mutation of NBN gene may constitute risk factor for solid tumors in children. The frequency of this mutation has been analyzed in patients with neuroblastoma (n=66), Wilms tumor (n=54), medulloblastoma (n=57), and rhabdomyosarcoma (n=82) hospitalized in Pediatric Oncology, Hematology and Bone Marrow Transplantation Department in the years between 1987 and 2010. About 2947 anonymous blood samples collected on Guthrie cards drawn from the newborn screening program of the Wielkopolska region have been used as controls. All the patients and controls came from the same geographical region. I171V mutation of the NBN gene has been observed in 5 controls. Among children with solid tumors only in 1 child with medulloblastoma I171V variant has been found. In conclusion, I171V germline mutation in contrary to adults cannot be considered as a risk factor for children malignancies. However, owing to low number of patients with solid tumors the possibility of a Type II error may exist.

Hypertensive Cardiomyopathy with Congestive Heart Failure in an Infant with Unilateral Wilms Tumor: A Case Report.

Wilms tumor (WT) is the most common malignant kidney tumor in children. High blood pressure is seen in up to 55% of children with WT. However, hypertensive cardiomyopathy with congestive heart failure due to WT is remarkably rare, with only several cases reported worldwide. In this report, a pediatric case of WT with hypertension causing hypertensive cardiomyopathy and congestive heart failure is presented. An 8-month-old male child with abdominal distension was seen by his primary physician. He was referred to our hospital for further examination and treatment. Abdominal contrast-enhanced computed tomography demonstrated a weakly enhancing, large abdominal mass, which was larger than 12 cm. Two-dimensional transthoracic echocardiography showed a diffuse hypokinetic left ventricle. The patient was diagnosed with cardiomyopathy caused by hypertension. Open surgical resection of the mass was successfully performed. His postoperative course was uncomplicated, and the patient was successfully discharged. The plasma renin activity was maintained at a high level even after left nephrectomy, suggesting that the right kidney was likely the source of renin secretion. Mechanical compression of the right renal blood vessels by a greatly enlarged left kidney can cause right renal ischemia, which activates renin excretion. Nephrectomy can be an effective treatment for a WT patient with hypertension causing hypertensive cardiomyopathy, and then cardiac function will be improved within several weeks. We recommend routine echocardiography surveillance in patients with WT. This report can help pediatric surgeons become more familiar with cardiomyopathy caused by WT.

Cystatin C and parenchymal thickness/kidney length ratio in Wilms tumor survivors.

BACKGROUND: This study presents a clinical, biochemical, and sonographic evaluation of single kidneys in Wilms tumor survivors. PROCEDURE: The function of single kidneys in 26 Wilms tumor survivors (mean age, 11.17 years; mean follow-up, 7.09 years) was evaluated using cystatin C (CysC) levels and compared to serum creatinine concentration and glomerular filtration rate (eGFR), the latter of which was estimated by the Schwartz formula. The length of the kidney, the resistance index (RI) of the renal vessels, and the parenchymal thickness/kidney length ratio (PT/KL) were evaluated by sonographic examination. RESULTS: Group A (n = 15) consisted of children with normal CysC levels, and group B (n = 11) consisted of children with CysC over 0.95 mg/L. No differences were observed between the groups in creatinine concentration, age, follow-up evaluation, age at the time of diagnosis, or kidney size. Children with elevated CysC had statistically lower eGFR (P = 0.02) and PT/KL (P = 0.0065). The correlation rate between CysC and PT/KL in all children was -0.38. Kidney hypertrophy was observed in 23 children and was correlated with CysC (group A, R = 0.46; group B, R = 0.4; P < 0.05). RI was normal in all individuals. CONCLUSIONS: CysC levels may be elevated in people with normal GFR. Hypertrophy of a single kidney increases with deteriorating kidney function. PT/KL should be verified in future studies as a sonographic marker of kidney impairment.