Cytogenetic findings in Polish patients with suspected Fanconi anemia.

BACKGROUND: The high sensitivity of cells of Fanconi anemia (FA) patients to DNA cross-linking agents (clastogens), such as mitomycin C (MMC), was used as a screening tool in Polish children with clinical suspicion of FA. OBJECTIVES: The aim of the study was to compare chromosome fragility between 3 groups, namely non-FA, possible mosaic FA and FA patients. MATERIAL AND METHODS: The study included 100 children with hematological manifestations and/or congenital defects characteristic of FA, and 100 healthy controls. Blood samples obtained from participants were analyzed using an MMC-induced chromosomal breakage test. RESULTS: Patients with clinical suspicion of FA were divided into 3 subgroups based on the MMC test results, namely FA, possible mosaic FA and non-FA. Thirteen out of 100 patients had a true FA cellular phenotype. The mean value of MMC-induced chromosome breaks/cell for FA patients was higher than for non-FA patients (6.67 ±3.92 compared to 0.23 ±0.18). In addition, the percentage of cells with spontaneous aberrations was more than 9 times higher in FA patients than in non-FA patients. CONCLUSIONS: Our results confirmed that the MMC sensitivity test distinguishes between individuals affected by FA, those with possible somatic mosaicism, and patients with bone marrow failure for other reasons, who were classified as non-FA in the first diagnostic step. However, a definitive differential diagnosis requires follow-up mutation testing and chromosome breakage analysis of skin fibroblasts.

Radical surgical treatment of neuroendocrine tumors of the appendix in children - a Polish multicenter study.

INTRODUCTION: The aim of the study was to examine management of pediatric appendiceal neuroendocrine tumors (ANETs) in Poland. METHODS: Records of 27 patients with ANET diagnosed incidentally after appendectomy in the last decade. RESULTS: Well-differentiated NET G1/G2 was diagnosed in 25 and well-differentiated neuroendocrine carcinoma G3 in 2 patients. Extended surgery was performed primarily in one instance and secondarily in 10 patients (right hemicolectomy in 9, ileocecal resection in 1) without adjuvant chemotherapy. Follow-up range was 1-121 months. Recurrence after secondary surgery was observed in 1 (3.7%) patient. CONCLUSIONS: Applying ENETS guidelines resulted in 100% overall survival of patients with NET.

Hematopoietic Stem Cell Transplantation Positively Affects the Natural History of Cancer in Nijmegen Breakage Syndrome.

PURPOSE: Nijmegen breakage syndrome (NBS) is a DNA repair disorder with a high predisposition to hematologic malignancies. EXPERIMENTAL DESIGN: We describe the natural history of NBS, including cancer incidence, risk of death, and the potential effectiveness of hematopoietic stem cell transplantation (HSCT) in preventing both pathologies: malignancy and immunodeficiency. RESULTS: Among 241 patients with NBS enrolled in the study from 11 countries, 151 (63.0%) patients were diagnosed with cancer. Incidence rates for primary and secondary cancer, tumor characteristics, and risk factors affecting overall survival (OS) were estimated. The cumulative cancer incidence was 40.21% ± 3.5% and 77.78% ± 3.4% at 10 years and 20 years of follow-up, respectively. Most of the tumors n = 95 (62.9%) were non-Hodgkin lymphomas. Overall, 20 (13.2%) secondary malignancies occurred at a median age of 18 (interquartile range, 13.7-21.5) years. The probability of 20-year overall survival (OS) for the whole cohort was 44.6% ± 4.5%. Patients who developed cancer had a shorter 20-year OS than those without malignancy (29.6% vs. 86.2%; P < 10-5). A total of 49 patients with NBS underwent HSCT, including 14 patients transplanted before malignancy. Patients with NBS with diagnosed cancer who received HSCT had higher 20-year OS than those who did not (42.7% vs. 30.3%; P = 0.038, respectively). In the group of patients who underwent preemptive transplantation, only 1 patient developed cancer, which is 6.7 times lower as compared with nontransplanted patients [incidence rate ratio 0.149 (95% confidence interval, 0.138-0.162); P < 0.0001]. CONCLUSIONS: There is a beneficial effect of HSCT on the long-term survival of patients with NBS transplanted in their first complete remission of cancer.

Clinical features and treatment outcomes of peripheral T-cell lymphoma in children. A current data report from Polish Pediatric Leukemia/Lymphoma Study Group (PPLLSG).

PURPOSE: Peripheral T-cell lymphomas (PTCL) are lymphoproliferative disorders derived from post-thymic cells, that occur extremely rarely in children. The optimal treatment of pediatric PTCL remains still unclear. PATIENTS AND METHODS: Ten children with PTCL from 3 up to 18 years of age registered by the Polish Pediatric Leukemia/Lymphoma Study Group (PPLLSG) were retrospectively analyzed. All patients were treated with different regimens including protocols: for lymphoblastic lymphoma in 7 cases, for anaplastic large cell lymphoma in 1, CHOP in 1. Five of the 10 patients with PTCL were classified as stage II; 4 as stage III and 1 as stage IV due to extralymphatic organs (bone marrow) involvement. Four histological subtypes of PTCL were recognized: extranodal NK/T-cell lymphoma, nasal type (ENTNT), peripheral T-cell lymphoma not otherwise specified (PTCL-NOS), subcutaneous panniculitis-like T-cell lymphoma (SPL), Sezary syndrome (SS). After first-line therapy 9 patients initially achieved complete remission, 4 relapsed, 5 died. One patient achieved remission spontaneously. Three children (1 with stage IV and 2 in relapse) underwent high-dose chemotherapy with allogeneic bone marrow stem cell transplantation and all of them are alive and in CR. RESULTS: The cumulative probability of 5-year overall survival (OS) for our whole group was 63.9% (95%CI: 35.2-88.2%) with a median follow-up time of 48.4 months (range 24-90+ months). The 5-year event free survival (EFS) was 81%. PTCLs are a heterogeneous and rare group of childhood NHLs. CONCLUSIONS: According to our experience the standard chemotherapy for precursor lymphomas seems to be a beneficial treatment option for children with PTCL. Allogeneic stem cell transplantation may improve the outcome in selected patients.

Upregulation of mitogen-activated protein kinase in ganglioglioma.

Ganglioglioma (GG) is a low-grade neoplasm, often associated with intractable epilepsy in pediatric patients. Available data suggest a relationship between GG and other glioneuronal lesions. So far, little is known about activation of kinases belonging to the mTor (mammalian target of rapamycin) pathway, although its upregulation is often found in brain tumors. Involvement of mTor kinase is responsible for excessive proliferation. In the current study we focused on the possible role of the Erk/Mapk (extracellular-signal-regulated kinase/mitogen-activated protein kinase) pathway in GG development. Eight GG tumors were resected from pediatric patients. Collected data reveal activation of proteins from the Erk pathway: Mek (extracellular regulated protein kinase kinase/mitogen-activated protein kinase kinase), Erk, Rsk1 (ribosomal S6 kinase 1), Rheb (Ras homolog enriched in brain) and Msk1 (mitogen- and stress-activated protein kinase 1), as detected by the western blot method. Moreover, activation of other proteins upstream of mTor - IGF-1R ß (insulin-like growth factor 1ß receptor), INR ß (insulin receptor ß), Akt/PKB (protein kinase B) - or downstream - 4E-BP1 (eukaryotic translation initiation factor 4E-binding protein 1) and rpS6 (ribosomal protein S6) - was also confirmed.

DNA methylation profiling of medulloblastoma allows robust subclassification and improved outcome prediction using formalin-fixed biopsies.

Molecular subclassification is rapidly informing the clinical management of medulloblastoma. However, the disease remains associated with poor outcomes and therapy-associated late effects, and the majority of patients are not characterized by a validated prognostic biomarker. Here, we investigated the potential of epigenetic DNA methylation for disease subclassification, particularly in formalin-fixed biopsies, and to identify biomarkers for improved therapeutic individualization. Tumor DNA methylation profiles were assessed, alongside molecular and clinical disease features, in 230 patients primarily from the SIOP-UKCCSG PNET3 clinical trial. We demonstrate by cross-validation in frozen training and formalin-fixed test sets that medulloblastoma comprises four robust DNA methylation subgroups (termed WNT, SHH, G3 and G4), highly related to their transcriptomic counterparts, and which display distinct molecular, clinical and pathological disease characteristics. WNT patients displayed an expected favorable prognosis, while outcomes for SHH, G3 and G4 were equivalent in our cohort. MXI1 and IL8 methylation were identified as novel independent high-risk biomarkers in cross-validated survival models of non-WNT patients, and were validated using non-array methods. Incorporation of MXI1 and IL8 into current survival models significantly improved the assignment of disease risk; 46 % of patients could be classified as 'favorable risk' (>90 % survival) compared to 13 % using current models, while the high-risk group was reduced from 30 to 16 %. DNA methylation profiling enables the robust subclassification of four disease subgroups in frozen and routinely collected/archival formalin-fixed biopsy material, and the incorporation of DNA methylation biomarkers can significantly improve disease-risk stratification. These findings have important implications for future risk-adapted clinical disease management.

Bacteria and Candida yeasts in inflammations of the oral mucosa in children with secondary immunodeficiency.

BACKGROUND: Oral microbial flora and a damaged oral mucosa may increase the risk of bacteriemia, fungemia and complications in immunocompromised patients. AIM OF THE STUDY: Assessment of presence: bacteria and Candida spp. in different oral lesions, and the incidence of bacteremia in the case of a damaged mucosa in transplant recipients and patients receiving anti-tumour chemotherapy. MATERIAL AND METHOD: Forty-five patients ­ 18 months to 18 years of life, were included (20 ­ organ recipients, 14­ anti-tumour chemotherapy, 11 ­ control group). Clinical, oral mucosa examination focused on the type, severity and site of lesions, and microbiology assessed the presence of bacteria and fungi in the material from lesions. Blood cultures were performed in ten immunocompromised patients with manifestations of systemic infection. The control material consisted of blood cultures made prior to the onset of oral lesions and after 4­6 weeks following their remission in a diagnosed bacteremia. The statistical analysis was performed. RESULTS: In the subjects with secondary immunodeficiency, among other coagulase-negative Staphylococcus (CoNS), Candidia spp. were more frequent. In cancer patients, mucositis was associated with Candida spp., Streptococcus spp. Organ recipients with stomatitis exhibited the presence of CoNS, Streptococcus viridians and other. Oral lesions in the control group contained Haemophilus parainfluenzae, Neisseria spp. and Staphylococcus aureus. In 30% of immunocompromised patients, oral lesions were accompanied by bacteremia. CONCLUSIONS: A correlation has been found between oral lesions and the presence of S. aureus in patients without secondary immunodeficiency, and of CoNS, Enterococcus spp., Candida spp. in immunocompromised patients.

Gait pathology assessed with Gillette Gait Index in patients after CNS tumour treatment.

Brain tumour is the third leading cause of death in children and adolescents younger than 16 years of age. The increasing survival rate of these patients makes their follow-up and quality of life assessment an important task. This study evaluated the gait pathology of the patients after the combined treatment for central nervous system (CNS) tumours. It assessed if the severity of gait deviation depended on the tumour site or age of illness onset. Gait analysis was performed on patients who completed the treatment (neurosurgery, chemo- and radiotherapy) and were disease-free at the time of the study. One hundred and five patients, 42 girls and 63 boys, aged 5-24 years of age, participated in the study. Depending on the location of the tumour, patients were divided into six groups. The Gillette Gait Index (GGI) was used to quantify gait deviation of patients compared to healthy subjects. Gait analysis was undertaken using VICON 460 movement analysis system. The Helen Hayes marker set was used, together with the Vicon Plug-in-Gait model. For each child the GGI was calculated separately for the left and right legs using data extracted from the subjects' averaged data. The results from left and right legs were then pooled together. To determine the effect of the tumour site and the onset of illness the ANOVA Kruskal-Wallis and correlation tests were used. The GGI did not depend on the tumour site, but demonstrated significant gait pathology in all patients. The age of illness onset appeared to influence the severity of gait deviation.

Prognostic significance of HER2 expression in neuroblastic tumors.

HER2 is essential for normal embryonic development and has a critical function in oncogenesis and progression of some types of cancer. Neuroblastic tumors create a heterogenous group of pediatric embryonal tumors of sympathoadrenal lineage. The biological and prognostic function of HER2 in these tumors is not well established. In this study, we evaluated the status of HER2, its prognostic significance, and clinicopathological correlations in series of 79 untreated neuroblastoma. The immunohistochemical assessment of HER2 and Ki-67 (proliferation index) as well as HER2 copy number status were performed on tissue microarrays. HER2 expression characterized 63 tumors, including 34 with low and 29 with high level, showing either membranous or mixed membranous-cytoplasmic pattern. Sixteen cases were HER2 immunonegative. The pattern of immunolabeling depended on the maturity of neuroblastic cells, being the most intense in differentiating neuroblasts. None of the tumors revealed HER2 amplification. In the examined group, 20% of patients died of disease from 4 to 107 months (median 18) from the diagnosis, and the survivors were followed up for 14-149 months (median 59). Patients' age, stage of disease, tumor location, mitosis/karyorrhexis index (MKI), and presence of HER2 expression were statistically significantly related to survival probability as detected by the Cox proportional hazard model. In the univariate analysis, Kaplan-Meier curves revealed significantly poorer outcome of HER2 negative than HER2-positive tumors (either low or high expression). The immunonegativity was associated with adverse clinicopathological parameters, including poor survival, metastatic stage of disease, un- or poorly differentiated histology, high MKI, and higher proliferation index. In conclusion, HER2 expression, not accompanied by gene amplification, is common in neuroblastic tumors. HER2 positivity seems to have a positive prognostic significance. HER2 expression with a variable pattern is a marker of the stage of neuroblastic cells differentiation.

Ganglioglioma associated with alterations of NBN gene. A case report.

We report a case of a 13-year-old girl with a tumour of the right fronto-parietal region of the brain. The tumour consisted of two components: a well-differentiated astroglial component with Rosenthal fibres and a neoplastic neuronal component. The final histopathology established diagnosis of ganglioglioma WHO grade I. The patient was selected from a group of children with central nervous system (CNS) tumours screened for the most common molecular variants in the NBN gene (exons 5 and 6). Molecular analysis revealed the presence of c.511A>G (p.Ile171Val) substitution on one allele. This is the first patient with ganglioglioma and confirmed mutation in the NBN gene.

[Bilateral papillary renal cell carcinoma in a patient post-renal transplantation]. / Obustronny rak "renal cell carcinoma" o typie brodawkowatym u pacjenta po transplantacji nerki.

Renal cancer accounts for about 2% of all cancers in general population. One of the risk factors is acquired cystic kidney disease developed in course of end- stage renal failure. About 2% of cases of renal cancer are associated with inherited syndromes. We present here the case of 18-year old boy with papillary bilateral renal cell carcinoma, which was found 3 years after renal transplantation, in the stage of graft failure, few days after graphtectomy, while looking for the reason of persistent fever.

Functional status of children after treatment for a malignant tumour of the CNS: a preliminary report.

The functional status of 41 paediatric patients after treatment for a malignant central nervous system (CNS) tumour was assessed using gait analysis and balance studies. Parameters of balance were obtained from stabilograms registered during "eyes-opened" and "eyes-closed" conditions. The patients could be divided into two groups: first, those with no deficits of balance, and second those with a balance deficit. The functional deficits exhibited by patients were not dependent on the tumour localization or age of onset of their illness. The mean time between the end of the treatment and the time of the study was 5.8 years in the non-deficit balance group, and 3.7 years in the balance deficit group (p=0.023). Children with a balance deficit tended to walk with a slightly higher speed, due to increased cadence. Their step width was slightly increased, as well as the percentage of the stance phase. They walked with increased external rotation at the hips and knee flexion at initial contact was slightly increased. The results suggest that patients can compensate the problems caused by oncology treatment, and indicate the need for early rehabilitation of CNS tumour patients.