[Oral cavity squamous cell carcinoma also occurs in children]. / Plaveiselcelcarcinoom in mondholte komt ook voor bij kinderen.

Squamous cell carcinoma in the head and neck area is rare in children and constitutes only 2% of malignancies. Between October 2019 and December 2020, 3 young, male patients presented at the Princess Máxima Centre for Paediatric Oncology with squamous cell carcinoma of the oral mucosa. All 3 had complaints of increasing, painful swelling in the oral cavity for weeks to months prior to the diagnosis. They had no risk factors for developing an oral malignancy and blank medical histories. In all 3 cases, there was a long delay preceding the diagnosis and the diagnosis was made at an advanced stage. Although rare, primary squamous cell carcinoma of the oral cavity can also occur in children.

Pleuropulmonary blastoma (PPB) and other DICER1-associated high-grade malignancies are morphologically, genetically and epigenetically related - A comparative study of 4 PPBs and 6 sarcomas.

DICER1-related tumors occur hereditary or sporadically, with high-grade malignancies sharing clinicopathological and (epi)genetic features. We compared 4 pleuropulmonary blastomas (PPBs) and 6 sarcomas by mutation analysis, whole transcriptome sequencing and methylation profiling. 9/10 patients were female. PPB patients were 0-4 years. 3/4 were alive; 2 without disease. One patient died of metastatic disease (median follow-up, 16 months). Sarcoma patients were 16-56 years. Locations included: uterine cervix/corpus (3/1), soft tissue back/shoulder (1) and paravertebral (1). 5/6 patients were alive; 2 developed metastases: intracranial (1) and lung and kidney (1) (median follow-up, 17 months). The deceased patient previously had a PPB and a Sertoli-Leydig cell tumor. Histologically, tumors showed atypical primitive-looking cells with incomplete rhabdomyoblastic differentiation and cartilage (n = 5). Immunohistochemistry demonstrated desmin- (n = 9/10), myogenin- (n = 6/10) and keratin positivity (n = 1/1). Eight cases harbored biallelic DICER1 mutations with confirmed germline mutations in 4 cases. Two cases showed a monoallelic mutation. By RNA expression- and methylation profiling, distinct clustering of our cases was seen demonstrating a close relationship on (epi)genetic level and similarities to embryonal rhabdomyosarcoma. In conclusion, this study shows overlapping morphological, immunohistochemical and (epi)genetic features of PPBs and DICER1-associated high-grade sarcomas, arguing that these neoplasms form a spectrum with a broad clinicopathological range.

In transit metastases in children, adolescents and young adults with localized rhabdomyosarcoma of the distal extremities: Analysis of the EpSSG RMS 2005 study.

In-transit metastases (ITM) are defined as metastatic lymph nodes or deposits occurring between the primary tumor and proximal draining lymph node basin. In extremity rhabdomyosarcoma (RMS), they have rarely been reported. This study evaluates the frequency, staging and survival of patients with ITM in distal extremity RMS. METHODS: Patients with extremity RMS distal to the elbow or knee, enrolled in the EpSSG RMS 2005 trial between 2005 and 2016 were eligible for this study. RESULTS: One hundred and nine distal extremity RMS patients, with a median age of 6.2 years (range 0-21 years) were included. Thirty seven of 109 (34%) had lymph node metastases at diagnosis, 19 of them (51%) had ITM, especially in lower extremity RMS. 18F-FDG-PET/CT detected involved lymph nodes in 47% of patients. In patients not undergoing 18F-FDG-PET/CT lymph node involvement was detected in 22%. The 5-yr EFS of patients with ITM vs proximal lymph nodes vs combined proximal and ITM was 88.9% vs 21.4% vs 20%, respectively (p = 0.01) and 5-yr OS was 100% vs 25.2% vs 15%, respectively (p = 0.003). CONCLUSION: Our study showed that in-transit metastases constituted more than 50% of all lymph node metastases in distal extremity RMS. 18F-FDG-PET/CT improved nodal staging by detecting more regional and in-transit metastases. Popliteal and epitrochlear nodes should be considered as true (distal) regional nodes, instead of in-transit metastases. Biopsy of these nodes is recommended especially in distal extremity RMS of the lower limb. Patients with proximal (axillary or inguinal) lymph node involvement have a worse prognosis.

Infantile fibrosarcoma with an EGFR kinase domain duplication: Underlining a close relationship with congenital mesoblastic nephroma and highlighting a similar morphological spectrum.

Infantile fibrosarcoma (IFS) and congenital mesoblastic nephroma (CMN) are locally aggressive tumors primarily occurring in infants. Both IFS and the cellular subtype of CMN show overlapping morphological features and an ETV6-NTRK3 fusion, suggesting a close relationship. An activating alteration of EGFR, based on an EGFR kinase domain duplication (KDD), occurs in a subset of CMNs lacking an NTRK3 rearrangement, especially in the classic and mixed type. So far no EGFR-KDDs have been detected in IFS. We describe four pediatric tumors at the extremities (leg, n = 2; foot and arm n = 1) with histological features of IFS/CMN. Two cases showed classic IFS morphology while two were similar to classic/mixed type CMN. In all cases, an EGFR-KDD was identified without detection of a fusion gene. There were no abnormalities of the kidneys in any of the patients. This is the first description of IFS with an EGFR-KDD as driver mutation, supporting that IFS and CMN are similar lesions with the same morphological and genetic spectrum. Pathologists should be aware of the more fibrous variant of IFS, similar to classic/mixed type CMN. Molecular analyses are crucial to treat these lesions adequately, especially with regard to the administration of tyrosine kinase inhibitors.

Neuroblastoma between 1990 and 2014 in the Netherlands: Increased incidence and improved survival of high-risk neuroblastoma.

PURPOSE: Long-term trends in neuroblastoma incidence and survival in unscreened populations are unknown. We explored trends in incidence, stage at diagnosis, treatment and survival of neuroblastoma in the Netherlands from 1990 to 2014. METHODS: The Netherlands Cancer Registry provided data on all patients aged <18 years diagnosed with a neuroblastoma. Trends in incidence and stage were evaluated by calculating the average annual percentage change (AAPC). Univariate and multivariable survival analyses were performed for stage 4 disease to test whether changes in treatment are associated with survival. RESULTS: Of the 593 newly diagnosed neuroblastoma cases, 45% was <18 months of age at diagnosis and 52% had stage 4 disease. The age-standardized incidence rate for stage 4 disease increased at all ages from 3.2 to 5.3 per million children per year (AAPC + 2.9%, p < .01). This increase was solely for patients ≥18 months old (3.0-5.4; AAPC +3.3%, p = .01). Five-year OS of all patients increased from 44 ± 5% to 61 ± 4% from 1990 to 2014 (p < .01) and from 19 ± 6% to 44 ± 6% (p < .01) for patients with stage 4 disease. Multivariable analysis revealed that high-dose chemotherapy followed by autologous stem cell rescue and anti-GD2-based immunotherapy were associated with this survival increase (HR 0.46, p < .01 and HR 0.37, p < .01, respectively). CONCLUSION: Incidence of stage 4 neuroblastoma increased exclusively in patients aged ≥18 months since 1990, whereas the incidence of other stages remained stable. The 5-year OS of stage 4 patients improved, mostly due to the introduction of high-dose chemotherapy followed by stem cell rescue and immunotherapy.

3-Methoxytyramine: An independent prognostic biomarker that associates with high-risk disease and poor clinical outcome in neuroblastoma patients.

INTRODUCTION: Prognosis of neuroblastoma patients is very diverse, indicating the need for more accurate prognostic parameters. The excretion of catecholamine metabolites by most neuroblastomas is used for diagnostic purposes, but their correlation with prognosis has hardly been investigated. Therefore, we performed an in-depth analysis of a panel of elevated urinary catecholamine metabolites at diagnosis and their correlation with prognosis. PATIENTS AND METHODS: Retrospective study of eight urinary catecholamine metabolites in a test (n = 96) and validation (n = 205) cohort of patients with neuroblastoma (all stages) at diagnosis. RESULTS: Multivariate analyses, including risk factors such as stage and MYCN amplification, revealed that 3-methoxytyramine (3MT) was an independent risk factor for event-free survival (EFS) and overall survival (OS). Furthermore, only 3MT appeared to be an independent risk factor for both EFS and OS in high-risk patients, which was independent of modern high-risk therapy and immunotherapy. Among high-risk patients, those with elevated 3MT and older than 18 months had an extremely poor prognosis compared to patients with non-elevated 3MT and younger than 18 months (5-year EFS of 14.3% ± 4% and 66.7% ± 18%, respectively, p = 0.001; 5-year OS of 21.8% ± 5% and 87.5% ± 12%, respectively, p < 0.001). CONCLUSIONS: Elevated 3MT at diagnosis was associated with high-risk disease and poor prognosis. For high-risk patients, elevated 3MT at diagnosis was the only significant risk factor for EFS and OS. 3MT was also able to identify subgroups of high-risk patients with favourable and extremely poor prognosis.

Feasibility, toxicity and response of upfront metaiodobenzylguanidine therapy therapy followed by German Pediatric Oncology Group Neuroblastoma 2004 protocol in newly diagnosed stage 4 neuroblastoma patients.

AIM OF THE STUDY: Radiolabelled meta-iodobenzylguanidine (MIBG) is an effective option in treatment of neuroblastoma (NBL) tumours. We studied feasibility, toxicity and efficacy of upfront 131I-MIBG and induction treatment in stage 4 NBL patients. PATIENTS AND METHODS: Retrospective, multi-centre (AMC and EMC) pilot regimen (1/1/2005-2011). Newly diagnosed stage 4 NBL patients, were treated with 2 courses of 131I-MIBG, GPOH 2004 NBL protocol, myeloablative therapy (MAT) and autologous stem cell rescue (ASCT). 131I-MIBG was administered in a fixed dose. Response rate (RR) was defined as complete remission, very good partial response and partial response. RESULTS: Thirty-two patients, (median age [range] 2.9 [0-11.4] years), 21 received 131I-MIBG therapy, 11 did not because of: MIBG non-avid (N = 5) and poor clinical condition (N = 6). In 95% of eligible patients 131I-MIBG treatment was feasible within 2 weeks from diagnosis. Interval between chemotherapy courses was 25 days (131I-MIBG group) versus 22 days (chemotherapy group). No stem cell support was needed after 131I-MIBG therapy. Stem cell harvest in both groups was feasible, neutrophil recovery was comparable, but platelet recovery post MAT, ASCT was slower for 131I-MIBG-treated patients. RR post 131I-MIBG was 38%, post MAT + ASCT was 71% (131I-MIBG group), 36% (chemotherapy group) and overall 59%. CONCLUSIONS: Induction therapy with 131I-MIBG before the HR GPOH NB 2004 protocol is feasible, tolerable and effective in newly diagnosed stage 4 NBL patients. 131I-MIBG upfront therapy induces early responses.

Synovial sarcoma in children and adolescents: the European Pediatric Soft Tissue Sarcoma Study Group prospective trial (EpSSG NRSTS 2005).

BACKGROUND: To report the results of the first European prospective nonrandomized trial dedicated to pediatric synovial sarcoma. PATIENTS AND METHODS: From August 2005 to August 2012, 138 patients <21 years old with nonmetastatic synovial sarcoma were registered in 9 different countries (and 60 centers). Patients were treated with a multimodal therapy including ifosfamide-doxorubicin chemotherapy and radiotherapy, according to a risk stratification based on surgical stage, tumor size and site, and nodal involvement. RESULTS: With a median follow-up of 52.1 months (range 13.8-104.4 months), event-free survival (EFS) was 81.9% and 80.7%, and overall survival (OS) was 97.2% and 90.7%, at 3 and 5 years, respectively. The only significant prognostic variable at univariate analysis was the risk group: 3-year EFS was 91.7% for low-risk, 91.2% for intermediate-risk, and 74.4% for high-risk cases. In 24 low-risk patients (completely resected tumor ≤5 cm in size) treated with surgery alone, there were two local relapses and no metastatic recurrences. Among 67 high-risk patients (unresected, or axial tumor or nodal involvement), 66 underwent surgery after neoadjuvant chemotherapy. Response to chemotherapy was 55.2%, including 22.4% cases with complete or major partial remissions, and 32.8% with minor partial remissions. CONCLUSION: This study demonstrates that collaborative prospective studies on rare pediatric sarcomas are feasible even on a European scale, with excellent treatment compliance. The overall results of treatment were satisfactory, with higher survival rates than those previously published by pediatric groups. Nonetheless, larger, international projects are needed, based on a cooperative effort of pediatric and adult oncologists. CLINICAL TRIALS NUMBER: European Union Drug Regulating Authorities Clinical Trials No. 2005-001139-31.

Prognostic significance of molecular-cytogenetic abnormalities in pediatric T-ALL is not explained by immunophenotypic differences.

Pediatric T-cell acute lymphoblastic leukemia (T-ALL) is characterized by chromosomal rearrangements possibly enforcing arrest at specific development stages. We studied the relationship between molecular-cytogenetic abnormalities and T-cell development stage to investigate whether arrest at specific stages can explain the prognostic significance of specific abnormalities. We extensively studied 72 pediatric T-ALL cases for genetic abnormalities and expression of transcription factors, NOTCH1 mutations and expression of specific CD markers. HOX11 cases were CD1 positive consistent with a cortical stage, but as 4/5 cases lacked cytoplasmatic-beta expression, developmental arrest may precede beta-selection. HOX11L2 was especially confined to immature and pre-AB developmental stages, but 3/17 HOX11L2 mature cases were restricted to the gammadelta-lineage. TAL1 rearrangements were restricted to the alphabeta-lineage with most cases being TCR-alphabeta positive. NOTCH1 mutations were present in all molecular-cytogenetic subgroups without restriction to a specific developmental stage. CALM-AF10 was associated with early relapse. TAL1 or HOX11L2 rearrangements were associated with trends to good and poor outcomes, respectively. Also cases with high vs low TAL1 expression levels demonstrated a trend toward good outcome. Most cases with lower TAL1 levels were HOX11L2 or CALM-AF10 positive. NOTCH1 mutations did not predict for outcome. Classification into T-cell developmental subgroups was not predictive for outcome.

[Influenza in children undergoing chemotherapy]. / Influenza bij kinderen die chemotherapie ondergaan.

Two paediatric cancer patients were found to have influenza shortly after receiving chemotherapy. Both presented with neutropenic fever. The first patient, a 15-year-old boy with Hodgkin's lymphoma, recovered without complications. The second patient, a 15-month-old-girl with metastatic Wilms' tumour, died due to severe infectious complications. These cases illustrate that common viruses, such as the influenza virus, can cause fulminant secondary infections in immunocompromised patients. Viruses, including the influenza virus, should always be considered as pathogens in patients with neutropenic fever, and influenza vaccination should be considered in these high-risk patients.

The catheter is stuck: complications experienced during removal of a totally implantable venous access device. A single-center study in 200 children.

BACKGROUND: Totally implantable venous access devices (TIVAD) facilitate repeat intravenous therapy for children. Many children recover and the device may be removed. Although removal should be a simple procedure via a single incision, in our experience, this has not been the case. METHODS: Two hundred consecutive cases of removal of TIVAD from September 2000 to January 2004 at Sophia Children's Hospital, Rotterdam, were reviewed. RESULTS: Average patient age was 5.9 years. The commonest indication for placement was administration of chemotherapy (88%); commonest indication for removal was remission of disease (70%). The median duration in situ of the catheter was 29 months (range, 0.4-91 months). Complications with removal of the polyurethane catheter of the TIVAD were experienced in 16% of cases. To enable removal, a second incision was required in 28 patients, venotomy in 5; the catheter could not be removed in 3. For all complicated removals the catheter had been in situ for longer than 20 months. CONCLUSIONS: Long-term implantation of TIVAD with polyurethane catheter appears unsuitable owing to a high incidence of complication at time of removal.

MDR1 expression in poor-risk acute myeloid leukemia with partial or complete monosomy 7.

Expression of the multidrug resistance (MDR1) phenotype, encoded by the MDR1 gene, is an adverse prognostic factor for CR and survival in acute myeloid leukemia (AML). Other prognostic factors, such as specific cytogenetic abnormalities, have been identified in AML. We have investigated the expression of the MDR1 gene in untreated AML patients with monosomy 7 (n = 12), and partial deletions (n = 7) of the long arm of chromosome 7 (respectively -7/7q-), because of the extremely bad prognosis associated with these cytogenetic abnormalities and because of the fact that the MDR1 gene is located on chromosome 7q21.1. The findings were compared with the level of MDR1 expression in a group of 42 other AML patients, matched for age with favourable, neutral or complex cytogenetic abberations. MDR1 mRNA expression, as measured by the RNase protection assay was significantly higher in the -7/7q- group vs other AML patients (median 1.3 vs 0.1 arbitrary units, P = 0.02). Protein expression of MDR1 in the -7/7q- group, as determined with the monoclonal antibody MRK16, was found to be similar to the levels found in the control group. With a functional rhodamine retention assay using the modulator PSC833, increased MDR1 activity was observed in the -7/7q- group as compared to the control group of patients (P = 0.05). Considering the higher MDR1 mRNA expression and equal or slightly elevated level of protein expression of MDR1, we studied the presence of MDR1 genes in this group of -7/7q- patients. Fluorescence in situ hybridization (FISH) studies, using a specific MDR1 probe revealed no loss of an MDR1 allele in any of the deleted q- arms of the seven patients with 7q-, whereas all monosomy 7 patients lacked one MDR1 gene homologue. To determine whether there was selective loss of the MDR1 gene in the -7/7q- patients, the genetic polymorphism of the MDR1 gene was used. Both allelic variants (G and T) were represented in the -7/7q- and in the control group, showing a predominance for GT at position 2677 of the MDR1 gene in the control group. In the 12 monosomy 7 patients loss of the MDR1 allele was random. Methylation studies of the CpG island of the MDR1 gene revealed no hypermethylation in any of the -7/7q- patients. We conclude that MDR1 expression in -7/7q- AML patients is upregulated at transcriptional, but not at translational level, suggesting that mechanisms other than MDR1 are responsible for the poor prognosis in these patients.

Microsatellite instability and promoter methylation as possible causes of NF1 gene inactivation in neurofibromas.

Neurofibromatosis type 1 (NF1) is a frequent hereditary disorder. One of the characteristic features of this disease is the development of neurofibromas. Since the NF1 gene is supposed to be a tumour suppressor gene, these neurofibromas should develop upon inactivation of both NF1 alleles. So far, mutation and deletion have been found to be involved in NF1 gene inactivation. However, these inactivating mechanisms explain the development of only a limited fraction of analysed neurofibromas. In this study, we investigated microsatellite instability (MSI) and promoter methylation as potential contributors to NF1 gene inactivation. As site-specific methylation in the NF1 promoter inhibits binding of transcription factors Sp1 and CREB, we studied the methylation status of their binding sites in particular. We analysed 20 neurofibromas and three neurofibrosarcomas, but did not find evidence for microsatellite instability or NF1 promoter methylation in any of the tumours. Thus, our data suggest that both microsatellite instability and promoter methylation are unlikely to be the major causes of NF1 gene inactivation in these tumours.

Transcriptional silencing of the p73 gene in acute lymphoblastic leukemia and Burkitt's lymphoma is associated with 5' CpG island methylation.

The p73 gene is located on 1p36.2-3, a region that is frequently deleted in human cancer. Because p73 encodes for a protein that is both structurally and functionally homologous to the p53 protein, p73 has been postulated to be a candidate tumor suppressor gene. To date, however, mutations of p73 have not been found. To study methylation of the p73 5'CpG island, a human bacterial artificial chromosome clone containing exon 1 and the 5' region of p73 was isolated. There was no evidence for p73 exon 1 methylation in normal tissues. In contrast, p73 was aberrantly methylated in approximately 30% of primary acute lymphoblastic leukemias (ALLs) and Burkitt's lymphomas. There was no evidence for methylation in any other types of hematological malignancies or solid tumors examined. In both leukemia cell lines and primary ALLs, methylation was associated with transcriptional loss of p73 by reverse transcription-PCR. We used single-strand conformational polymorphisms to screen for point mutations in a series of primary ALLs and found no mutations leading to a change in protein structure. Our results show that methylation of p73 is a frequent event in specific types of hematological malignancies and suggest that epigenetic silencing of p73 could have important consequences for cell-cycle regulation.

Neuroblastoma 4S: a heterogeneous disease with variable risk factors and treatment strategies.

BACKGROUND: Despite the excellent prognosis for neuroblastoma 4S (NBL 4S; with S indicating "special"), 10-25% of these patients nevertheless do not survive. Since the first description of this subgroup of disseminated neuroblastoma with a favorable natural outcome, treatment modalities have become milder. Current treatment strategies range from observation with supportive care to full cycles of chemotherapy, radiation therapy, and/or surgical removal of the primary tumor. METHODS: A recent case of NBL 4S seen at the Sophia Children's Hospital led the authors to review their patient charts from 1971 onward, as well as the literature, for the treatment modalities used and the outcome in treated versus nontreated patients. RESULTS: In addition to the presented case and five additional cases from the authors' patient files, the literature contained 113 reported cases. Of a total of 119 cases, 33 patients died, 12 as a result of hepatomegaly with renal impairment and/or respiratory failure. All but 1 of these patients were diagnosed in the first 4 weeks of life. Of the 33 patients who died, 45% progressed to Stage 4 metastatic disease (15 of 33), a finding that appeared to be unrelated to age. N-myc amplification data were available in 30 cases. Seventeen patients had < or = 3 gene copies; 12% of these patients (2 of 17) died. In the N-myc-amplified group of patients with > 3 gene copies, 69% (9 of 13) died and another patient progressed to Stage 4 with short follow-up. CONCLUSIONS: The data presented here suggest an important role for age as a prognostic factor. The very young NBL 4S patient (age < 4 weeks at diagnosis) was at high risk of dying of (respiratory) complications as a result of massive hepatomegaly. In contrast, disease progression to Stage 4 appears to be unrelated to age, but is strongly related to the presence of biologic markers in the tumor. The authors propose a therapeutic approach for very young patients and for those with unfavorable biology.