Impact of COVID-19 on paediatric chronic intestinal failure: A tertiary care children's hospital experience

OBJECTIVES

Paediatric patients with intestinal failure (IF) are at risk for both gastrointestinal (GI) and systemic complications, thus depending on a functioning network of multidisciplinary care. Data on the clinical impact of coronavirus disease 2019 (COVID-19) or the pandemic-related restrictions are limited. We aimed to analyse the clinical course of COVID-19 in children with IF, and to evaluate the perceived impact of the COVID-19 pandemic on IF patients and their caregivers by analysing quality of life (QoL), health-related QoL (HRQoL) and health care.

METHODS

Children with IF presenting at our intestinal rehabilitation centre were enrolled and interviewed about test-proven COVID-19 infection. A standardised questionnaire was offered to all caregivers of IF patients and to two control groups (children with inflammatory bowel disease and gastrointestinal healthy children).

RESULTS

Between December 2020 and November 2022, 25 out of 127 patients with IF contracted COVID-19. Forty-eight per cent had GI symptoms, 32% required additional intravenous fluids and 20% were hospitalized. Only 25% of vaccinated children showed signs of GI dysfunction, compared to 52% of unvaccinated children. Analysis of 93 questionnaires showed a negative impact on QoL and HRQoL (>66.7% and >27.8%, respectively). IF patients frequently experienced restrictions in health care, including appointments, services and supply of parenteral nutrition or medications. Caregiver burden increased significantly more often in caregivers of children with IF (p = 0.007).

CONCLUSIONS

Paediatric patients with IF contracting COVID-19 have an increased risk for GI dysfunction which may be alleviated by vaccination. Children and their caregivers were highly burdened by pandemic-related restrictions and reductions in health care provision.

Combined Metabolic and Functional Tumor Volumes on [18F]FDG-PET/MRI in Neuroblastoma Using Voxel-Wise Analysis

PURPOSE

The purpose of our study was to evaluate the association between the [18F]FDG standard uptake value (SUV) and the apparent diffusion coefficient (ADC) in neuroblastoma (NB) by voxel-wise analysis.

METHODS

From our prospective observational PET/MRI study, a subcohort of patients diagnosed with NB with both baseline imaging and post-chemotherapy imaging was further investigated. After registration and tumor segmentation, metabolic and functional tumor volumes were calculated from the ADC and SUV values using dedicated software allowing for voxel-wise analysis. Under the mean of thresholds, each voxel was assigned to one of three virtual tissue groups: highly vital (v) (low ADC and high SUV), possibly low vital (lv) (high ADC and low SUV), and equivocal (e) with high ADC and high SUV or low ADC and low SUV. Moreover, three clusters were generated from the total tumor volumes using the method of multiple Gaussian distributions. The Pearson's correlation coefficient between the ADC and the SUV was calculated for each group.

RESULTS

Out of 43 PET/MRIs in 21 patients with NB, 16 MRIs in 8 patients met the inclusion criteria (PET/MRIs before and after chemotherapy). The proportion of tumor volumes were 26%, 36%, and 38% (v, lv, e) at baseline, 0.03%, 66%, and 34% after treatment in patients with response, and 42%, 25%, and 33% with progressive disease, respectively. In all clusters, the ADC and the SUV correlated negatively. In the cluster that corresponded to highly vital tissue, the ADC and the SUV showed a moderate negative correlation before treatment (R = -0.18; p < 0.0001) and the strongest negative correlation after treatment (R = -0.45; p < 0.0001). Interestingly, only patients with progression (n = 2) under therapy had a relevant part in this cluster post-treatment.

CONCLUSION

Our results indicate that voxel-wise analysis of the ADC and the SUV is feasible and can quantify the different quality of tissue in neuroblastic tumors. Monitoring ADCs as well as SUV levels can quantify tumor dynamics during therapy.

Nephron sparing surgery and surgical management of intravascular extension of Wilms tumor

Although general treatment approaches for Wilms tumor differ between Children's Oncology Group and Société Internationale d'Oncologie Pédiatrique-Renal Tumors Study Group protocols, complex tumors that may be candidates for nephron sparing surgery (NSS) and those with intravascular tumor extension represent a management challenge. In both of these scenarios, anatomic considerations are important in guiding management, making these areas of significant similarities in management between the international groups. This paper aims to explore the current approaches to NSS and intravascular tumor extension by both international groups, with attention to the evidence supporting these approaches and current knowledge gaps.

Correction to: Surgical management of peripheral nerve sheath tumours in children, with special consideration of neurofibromatoses

A correction to this paper has been published: https://doi.org/10.1007/s00381-021-05228-2

Fatty acid composition of adipose tissue at term indicates deficiency of arachidonic and docosahexaenoic acid and excessive linoleic acid supply in preterm infants

BACKGROUND

Arachidonic (ARA) and docosahexaenoic acid (DHA) are constitutive to membrane phospholipids, and essential for brain and overall development. ARA/DHA pools in term infants (TI) are built during the third trimester, stored as adipose tissue triglycerides and predominantly distributed via plasma phosphatidylcholine (PC). In preterm infants (PTI), placental ARA/DHA supply is replaced by linoleic-acid (LA)-enriched nutrition. This study aimed to investigate the impact of PTI nutrition, compared to placental supply, on fatty acid composition in adipose tissue and blood.

METHODS

Prospective observational study (4/2017-3/2019) in 12 PTI and 3 PTI with enterostomy (PTI/E) (gestational age (GA) < 32 weeks) with surgical intervention at term (± 6 weeks) and 14 TI (GA ≥ 34 weeks, surgical intervention < 2 weeks postnatally). PTI/E were analyzed descriptively only. PC and triglyceride fatty acids were analyzed with tandem mass spectrometry and gas chromatography, respectively. Results were compared between TI and PTI with Wilcoxon Test and shown as median [25th percentile-75th percentile] mol%.

RESULTS

PTI had less ARA in adipose tissue TG (0.77[0.67-0.87]% vs. 1.04[0.95-1.14]%, p = 0.0003) and plasma PC (20.7[18.7-22.8]% vs. 28.3[22.7-33.5]%, p = 0.011) than TI. PTI also had less DHA in adipose tissue TG (0.6[0.4-0.8]% vs. 1.1[0.8-1.4]%, p = 0.006) and plasma PC (6.4[5.6-7.1]% vs. 8.4[7.8-13.1]%, p = 0.002). LA was increased in PTI's adipose tissue TG (10.0[8.8-12.3]% vs. 3.0[2.5-3.6]%, p < 0.0001) and plasma PC (48.4[44.6-49.6]% vs. 30.6[24.9-35.6]%, p = 0.0002). Similar differences were observed in erythrocyte PC.

CONCLUSION

In PTI, LA is increased and ARA/DHA decreased in adipose tissue, plasma and erythrocyte lipids as proxies for other tissues, likely caused by PTI nutrition. This may contribute to impaired PTI development.

Local Stage Dependent Necessity of Radiation Therapy in Rhabdoid Tumors of the Kidney (RTK)

PURPOSE

Rhabdoid tumor of the kidney (RTK) is one of the most aggressive childhood renal tumors. Overall survival ranges from 22% to 47%. The indication for radiation therapy (RT) in usually very young patients is an ongoing discussion. Recent protocols recommend RT independent of local stage, the latter being a good discriminator in other childhood kidney tumors. In this study, we analyze the evidence for RT in regard to risk factors, including tumor stage.

METHODS AND MATERIALS

This study analyzed 58 patients with RTK from Austria, Switzerland, and Germany treated in the framework of 4 consecutive, prospective renal/rhabdoid tumor studies from 1991 to 2014. All treatment protocols included multimodality treatment, including high-intensity chemotherapy, surgery, and RT.

RESULTS

Local stage distribution was not applicable, I, II, and III in 1, 6, 11, and 40, respectively. Twenty-nine (50%) patients had stage IV disease at diagnosis. Thirty-seven patients (64%) achieved complete remission, and 49% (18/37) relapsed. Thirty-four patients (60%) patients had progressive disease and died, 17 had local disease, 10 had combined disease, and 7 had distant disease; 2 treatment-related deaths were reported (3%). Twenty-one patients received RT during first-line treatment, 18 of them to all involved sites. Eight of the 34 cases of progressive disease occurred in irradiated patients. The local failure rate of treated patients with local stage II or III disease was 29% (6/18) in patients irradiated to all sites compared with 68% (15/22) in nonirradiated patients. One of 6 stage I patients received RT, and 1 patient experienced distant relapse (2-year progression-free and overall survival both 83% ± 15%). Progression-free survival for local stage II and III disease treated with RT, adjusted for early relapse or treatment abandonment, was 67% ± 11%, compared with 15% ± 7% without RT (P < .0001).

CONCLUSION

The 68% local failure rate in nonirradiated patients underlines the importance of local treatment. Our experience supports the use of RT for local control in higher stage disease. In contrast, no local relapse in 6 local stage I patients, including 5 nonirradiated patients, suggests omission of RT in this favorable subset of usually infant patients with RTK.

Surgical management of peripheral nerve sheath tumours in children, with special consideration of neurofibromatoses

INTRODUCTION

Peripheral nerve sheath tumours in children are a rare and heterogeneous group, consisting mostly of benign tumours as well as malignant neoplasms. Especially in the paediatric population, diagnostics and indication for therapy pose relevant challenges for neurosurgeons and paediatric neurologists alike. Most paediatric cases that need surgical intervention are associated to neurofibromatosis type 1 (NF1).

METHODS

We retrospectively reviewed all paediatric cases treated at the Department of Neurosurgery in Tübingen between 2006 and 2017 for peripheral nerve sheath tumours. We analysed clinical signs, symptoms, histology, association to an underlying phacomatosis and sensory/motor function.

RESULTS

Of the 82 identified patients, the majority had NF1 (76.8%). Nine children bore a sporadic tumour without underlying phacomatosis (11%), 8 had NF2 (9.8%) and 2 schwannomatosis (2.4%), A total of 168 surgical interventions were performed, and 206 tumours were removed. Indication for surgery was in most instances significant tumour growth (45.2%) followed by pain (33.9%). New deficits led to surgery in 12.5% of interventions; malignancy was suspected in 8.3%. Histopathology revealed mostly neurofibromas (82.5%), divided into cutaneous neurofibromas (10.7%), infiltrating plexiform neurofibromas (25.7%) and peripheral nerve-born neurofibromas (46.1%). 12.1% of tumours were schwannomas, 2.9% MPNST, 1.5% ganglioneuroma (n = 3) and 1 hybrid-neurofibroma and perineurinoma each. Leading symptoms, such as pain and motor and sensory deficits, improved after 125/166 interventions (74.4%), remained unchanged following 39 interventions (23.2%) and worsened in 4 occasions (2.4%).

CONCLUSION

Surgery is safe and effective for (neurofibromatosis associated) peripheral nerve sheath tumours in the paediatric population; however, management needs a multidisciplinary setting. We propose early surgical resection in paediatric patients with peripheral nerve sheath tumours with significant growth, or pain, or motor deficit, or suspected malignancy.

High-dose treatment for malignant rhabdoid tumor of the kidney: No evidence for improved survival-The Gesellschaft für Pädiatrische Onkologie und Hämatologie (GPOH) experience

BACKGROUND

Malignant rhabdoid tumor of the kidney (MRTK) is the most aggressive childhood renal tumor with overall survival (OS) rates ranging from 22% to 42%. Whether high-dose chemotherapy with autologous stem-cell transplantation (HDSCT) in an intensive first-line treatment offers additional benefit is an ongoing discussion.

METHODS

A retrospective analysis of all 58 patients with MRTK from Austria, Switzerland, and Germany treated in the framework of consecutive, prospective renal/rhabdoid tumor studies SIOP9/GPO, SIOP93-01/GPOH (where SIOP is International Society of Pediatric Oncology and GPOH is German Society of Pediatric Oncology and Hematology), SIOP2001/GPOH, and European Rhabdoid Tumor Registry from 1991 to 2014.

RESULTS

Median age at diagnosis was 11 months. Fifty percent of patients had metastases or multifocal disease at diagnosis (Stage IV). Local stage distribution was as follows: not done/I/II/III-1/6/11/40. Fifteen (26%) patients underwent upfront surgery. Thirty-seven (64%) patients achieved a complete remission, 17 (29%) relapsed, 34 (59%) died of disease progression, and two (3%) died of treatment-related complication. Mean time to the first event was 3.5 months. Two-year EFS/OS (where EFS is event-free survival) for the whole group was 37 ± 6%/38 ± 6%. Metastases/multifocal disease, younger age, and local stage III were associated with significantly inferior survival. Eleven (19%) patients underwent HDSCT (carboplatin + thiotepa, n = 6; carboplatin + etoposide + melphalan, n = 4; others, n = 1); 2-year OS in this group was 60 ± 15% compared to 34 ± 8% in the non-HDSCT group (P = 0.064). However, the time needed from radiologic to histologic diagnosis, stem-cell harvest, and HDSCT must also be taken into account to avoid selection bias by excluding the highest risk group with early progression (<90 days). Thus, 2-year EFS only for patients without progression until day 90 was 60 ± 16% consolidated by HDSCT compared to 62 ± 11% without (P = 0.8).

CONCLUSION

Our retrospective analysis suggests comparable outcomes for patients with and without HDSCT, if adjusted for early disease progression.

Effects of curcumin in pediatric epithelial liver tumors: inhibition of tumor growth and alpha-fetoprotein in vitro and in vivo involving the NFkappaB- and the beta-catenin pathways

In children with hepatocellular carcinoma (pHCC) the 5-year overall survival rate is poor. Effects of cytostatic therapies such as cisplatin and doxorubicin are limited due to chemoresistance and tumor relapse. In adult HCC, several antitumor properties are described for the use of curcumin. Curcumin is one of the best-investigated phytochemicals in complementary oncology without relevant side effects. Its use is limited by low bioavailability. Little is known about the influence of curcumin on pediatric epithelial hepatic malignancies. We investigated the effects of curcumin in combination with cisplatin on two pediatric epithelial liver tumor cell lines. As mechanisms of action inhibition of NFkappaB, beta-catenin, and decrease of cyclin D were identified. Using a mouse xenograft model we could show a significant decrease of alpha-fetoprotein after combination therapy of oral micellar curcumin and cisplatin. Significant concentrations of curcuminoids were found in blood samples, organ lysates, and tumor tissue after oral micellar curcumin administration. Micellar curcumin in combination with cisplatin can be a promising strategy for treatment of pediatric HCC.

Inducing Differentiation of Premalignant Hepatic Cells as a Novel Therapeutic Strategy in Hepatocarcinoma

Hepatocellular carcinoma (HCC) represents the second leading cause of cancer-related deaths and is reported to be resistant to chemotherapy caused by tumor-initiating cells. These tumor-initiating cells express stem cell markers. An accumulation of tumor-initiating cells can be found in 2% to 50% of all HCC and is correlated with a poor prognosis. Mechanisms that mediate chemoresistance include drug export, increased metabolism, and quiescence. Importantly, the mechanisms that regulate quiescence in tumor-initiating cells have not been analyzed in detail so far. In this research we have developed a single cell tracking method to follow up the fate of tumor-initiating cells during chemotherapy. Thereby, we were able to demonstrate that mCXCL1 exerts cellular state-specific effects regulating the resistance to chemotherapeutics. mCXCL1 is the mouse homolog of the human IL8, a chemokine that correlates with poor prognosis in HCC patients. We found that mCXCL1 blocks differentiation of premalignant cells and activates quiescence in tumor-initiating cells. This process depends on the activation of the mTORC1 kinase. Blocking of the mTORC1 kinase induces differentiation of tumor-initiating cells and allows their subsequent depletion using the chemotherapeutic drug doxorubicin. Our work deciphers the mCXCL1-mTORC1 pathway as crucial in liver cancer stem cell maintenance and highlights it as a novel target in combination with conventional chemotherapy. Cancer Res; 76(18); 5550-61. ©2016 AACR.

High-pitch computed tomography of the lung in pediatric patients: an intraindividual comparison of image quality and radiation dose to conventional 64-MDCT

PURPOSE

The aim of this study was to investigate frequencies of typical artifacts in low-dose pediatric lung examinations using high-pitch computed tomography (HPCT) compared to MDCT, and to estimate the effective radiation dose (Eeff).

MATERIALS AND METHODS

Institutional review board approval for this retrospective study was obtained. 35 patients (17 boys, 18 girls; mean age 112 ± 69 months) were included and underwent MDCT and follow-up scan by HPCT or vice versa (mean follow-up time 87 days), using the same tube voltage and current. The total artifact score (0 - 8) was defined as the sum of artifacts arising from movement, breathing or pulsation of the heart or pulmonary vessels (0 - no; 1 - moderate; 2 - severe artifacts). Eeff was estimated according to the European Guidelines on Quality Criteria for Multislice Computed Tomography. The Mann-Whitney U test was used to analyze differences between the patient groups. The Spearman's rank correlation coefficient was used for correlation of ordinal variables.

RESULTS

The scan time was significantly lower for HPCT compared to MDCT (0.72 ± 0.13 s vs. 3.65 ± 0.81s; p < 0.0001). In 28 of 35 (80 %) HPCT examinations no artifacts were visible, whereas in MDCT artifacts occurred in all examinations. The frequency of pulsation artifacts and breathing artifacts was higher in MDCT compared to HPCT (100 % vs. 17 % and 31 % vs. 6 %). The total artifact score significantly correlated with the patient's age in MDCT (r = - 0.42; p = 0.01), but not in HPCT (r = - 0.32; p = 0.07). The estimated Eeff was significantly lower in HPCT than in MDCT (1.29 ± 0.31 vs. 1.47 ± 0.37 mSv; p < 0.0001).

CONCLUSION

Our study indicates that the use of HPCT has advantages for pediatric lung imaging with a reduction of breathing and pulsation artifacts. Moreover, the estimated Eeff was lower. In addition, examinations can be performed without sedation or breath-hold without losing image quality.

KEY POINTS

• Fewer artifacts in pediatric lung imaging with HPCT• Reduced Eeff in HPCT• HPCT without sedation or breath-hold without loss of image quality.

Fast intraoperative testosterone assay confirms the location of an ovarian virilizing tumor in a young girl

The detection of testosterone-producing ovarian tumors in childhood and adolescence by imaging techniques only can be difficult because of the tumors' radiological structure and sometimes diminutive size. We describe an 11.5-year-old girl with a 9-month history of voice deepening, mild hirsutism, minor acne, increased growth velocity, weight gain, and clitoromegaly. Laboratory investigation revealed an extremely elevated serum testosterone level without any additional endocrine abnormalities. Abdominal ultrasound and MRI showed a sparsely noticeable solid mass in the center of the right ovary. At laparotomy, blood was selectively drawn from the right and the left ovarian veins. Rapid testosterone measurement revealed a 70-fold higher testosterone concentration in the right ovarian vein within 45 min. Based on this finding, a right salpingo-oophorectomy was performed. The patient's postoperative testosterone level declined within 24 h. The histopathological diagnosis was Leydig cell tumor. In conclusion, the implementation of a fast intraoperative testosterone assay enabled the localization and curative therapy of a Leydig cell tumor. This technique seems to be a good alternative to preoperative selective venous blood sampling when body imaging does not unveil the tumor's site.

Animal models of extracranial pediatric solid tumors

Animal models, including xenografts, models of metastatic invasion, syngeneic models and transgenic models, are important tools for basic research in solid pediatric tumors, while humanized animal models are useful for novel immunotherapeutical approaches. Optical and molecular imaging techniques are used for in vivo imaging and may be used in conjunction with alternative treatment approaches, including photodynamic therapy. The aim of this review is to highlight the various animal models that may be used for basic research in pediatric solid tumors.

Abstract 4337: Effect of sorafenib in combination with cytostatic agents on hepatoblastoma in vitro and in vivo

Background: Hepatoblastoma (HB) represents the most common malignant liver tumour in childhood. For patients with high risk or recurrent HB treatment results remain still poor due to a developing multidrug resistance during chemotherapy. Therefore new therapy strategies have to be evaluated. The primary objective was to investigate the combined therapy of cytotoxic agents with sorafenib. Sorafenib has been shown to reduce tumour progression and angiogenesis. In order to investigate a treatment close to a clinical setting the effect of the combined administration of cytotoxic agents with sorafenib on HB cell lines and xenotransplanted HB tumours was determined. Methods: Cell viability of two HB cell lines (HUH6 and HepT1) was evaluated in using MTT assays after treatment with sorafenib and different cytostatic agents (cisplatin (CDDP), doxorubicin, irinotecan, topotecan). ERK signalling was investigated by Western blot analysis. NMRI mice (nu/nu) bearing subcutaneous HUH6 derived tumours were treated with Sorafenib orally (30 mg/kg, on days 4-13 and 17-24) alone or in combination with CDDP i.p. (3 mg/kg, on days 1-3 and 14-16). Tumor progression and viability were monitored by tumour volume and AFP levels. Apoptosis was assessed by TUNEL assay. Angiogenesis was determined by CD31 staining and mean vascular density (MVD) was calculated. Results: In vitro the combination of sorafenib with CDDP showed a remarkable decrease in cell viability compared to the other agents tested. However with increasing concentrations of CDDP this additive effect disappeared. CDDP alone showed an enhanced phosphorylation of ERK1/2, which is a common pathway for apoptosis induction through NOXA. CDDP in combination with sorafenib led to an overall reduced phosphorylation level of ERK1/2, which also resulted in a low HB cell viability. Since CDDP and sorafenib have an opposing effect on phosphorylation of ERK1/2, we avoid the concomitant administration of both drugs in vivo. In HB xenografts both sorafenib alone or in alternating combination with CDDP reduced tumour growth compared to the control untreated group (p &lt; 0.05). The combination treatment showed a higher and earlier reduction of tumor volume than sorafenib alone. In addition AFP levels did not significantly change in the treatment groups. Apoptotic areas as determined by TUNEL analysis increased significantly after administration of sorafenib or sorafenib and CDDP (p &lt; 0.08). Furthermore CD31 staining showed a significant inhibition of angiogenesis as revealed by determination of the MVD in both treatment groups (p &lt; 0.02). Discussion: Taken together the combination therapy of Sorafenib and CDDP led to an enhanced decrease in cell viability as well as in tumour progression and angiogenesis than sorafenib alone. Therefore a combined therapy might be a promising option in the treatment of high risk or recurrent hepatoblastoma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4337. doi:1538-7445.AM2012-4337

Pancreatoblastoma: a report from the European cooperative study group for paediatric rare tumours (EXPeRT)

BACKGROUND

Pancreatoblastoma is a very rare malignant tumour typically occurring in the early years of life. Due to its rarity, standardised diagnostic and therapeutic guidelines are not available for pancreatoblastoma.

METHODS

The newborn cooperative group denominated EXPeRT - European cooperative study group for paediatric rare tumours - combined in a joint analysis of all cases registered between 2000 and 2009 by the national groups of Italy, France, United Kingdom, Poland and Germany.

RESULTS

Twenty patients <18years old (median age 4years) were analysed: nine had distant metastases at diagnosis. Seventeen patients had tumour resection, at initial or delayed surgery. Eighteen received chemotherapy (response rate 73%), seven received radiotherapy. For the whole series, 5-year event-free survival and overall survival were 58.8% and 79.4%, respectively. Outcome did not correlate with tumour site and size, but was strongly influenced by the feasibility of tumour complete resection.

CONCLUSIONS

This international study confirms the rarity of the disease, the critical role of surgical resection both as therapy and as a prognostic variable, and the potential efficacy of chemotherapy. The adoption of an intensive multidisciplinary approach is required, as well as the referral to highly experienced centres. Further international cooperation is needed to collect larger series and stimulate biological studies to improve our understanding of the biology and the natural history of PBL.

CD155 is involved in NK-cell mediated lysis of human hepatoblastoma in vitro

NK cells are involved in the lysis of different solid tumors and leukemias. NK-activity is thereby regulated by activating and inhibitory receptors. Until now, nothing is known about the NK-activity against hepatoblastoma and the involved receptors. We tested NK cells for cytotoxicity against HB in vitro. Expression levels of activating NK ligands were analysed on 13 primary HB samples as well as on 3 HB cell lines. All HB cell lines showed low HLA-class-I-expression. CD155 expression was strong on primary HB samples and cell lines. NKG2D-ligands (MICA/B, ULBP1-3) were heterogeneous expressed in primary samples and cell cultures. There were no differences between the various histological subtypes. NK cells showed strong cytotoxicity in vitro which was significantly increased through interleukin-2 and -15 stimulation (p less than 0.001). Blockade of CD155 resulted in decreased lysis rates. Our findings show that NK cells exert high activity against hepatoblastoma in vitro and that CD155 is involved in the NK mediated killing of HB. The inclusion of a NK-based immunotherapy into novel treatment strategies might be a promising alternative especially for advanced tumors.

P-glycoprotein modulation improves in vitro chemosensitivity in malignant pediatric liver tumors

BACKGROUND

Multidrug resistance (MDR) is a major reason for the poor outcome of advanced pediatric liver malignancies. The P-glycoprotein (P-gP), which contributes to this phenomenon, has been potently antagonized in other tumors. Our aim was to investigate the influence of P-gP antagonizers on the chemotherapy of pediatric liver malignancies in vitro.

MATERIALS AND METHODS

One hepatocellular carcinoma (HCC) and three hepatoblastoma (HB) cell lines were incubated with doxorubicin or cisplatin. Additional effects of three P-gP-modulators were determined in a cytotoxicity assay. Expression levels of the MDR1 gene were determined using rT-PCR.

RESULTS

Modulation of P-gP improved chemotherapy results in all HB cell lines, more effectively in the more highly differentiated tumors. Combined treatment of the HCC cell line was only more efficient using doxorubicin and PSC 833.

CONCLUSION

Modulation of P-gP can overcome MDR in HCC and HB in vitro. Our data encourage further studies analyzing this effect under in vivo conditions.

Interventional treatment of infantile hepatic hemangioendothelioma

BACKGROUND/PURPOSE

Hemangioendothelioma is the most frequent liver tumor in infancy. Untreated symptomatic patients with heart failure have a high mortality rate. Symptomatic forms may request nonoperative treatment, because surgery is burdened with high risks in patients with heart failure. The authors report their experience with interventional coil occlusion of infantile hepatic hemangioendothelioma (IHE).

METHODS

Four patients (age range, 2 to 146 days; mean, 53 days) suffering from IHE associated with heart failure were treated by endovascular coil occlusion of arterial feeders. Catheter intervention was performed via an arterial (n = 2) or venous (n = 2) approach.

RESULTS

Signs of heart failure resolved within 2 to 8 days after occlusion in 3 patients. Tumor regression could be observed sonographically within 4 weeks postinterventionally. In 3 children, tumor size was reduced from a mean of 544 mL (65 to 1,350) to a mean of 4 mL (2 to 6); Mean systolic peak velocity in the hepatic artery was decreased from 170 cm/s (140 to 200) before occlusion to 45 cm/s (36 to 70) during follow-up. In the fourth patient, endovascular intervention could not control a rapidly progressing hemangioendotheliomatosis, and finally a liver transplantation had to be performed.

CONCLUSIONS

Interventional occlusion of feeding arteries in symptomatic IHE is a safe and effective alternative to early open surgery. The efficacy of endovascular intervention in multifocal tumors seems questionable.

A prospective study of minimally invasive techniques in pediatric surgical oncology: preliminary report

BACKGROUND

Thoracoscopic and laparoscopic techniques play a major role in pediatric surgery. However, minimally invasive surgery (MIS) has not yet established itself in pediatric surgical oncology. The authors present a prospective study investigating the role of MIS in children with cancer.

PROCEDURE

All children with abdominal or thoracic tumors requiring surgery were registered between September, 2000 and February, 2002. Decisions regarding procedures and approaches-conventional or minimally invasive-were made by the interdisciplinary team. Data on diagnoses, surgical procedures, complications, and conversion rates were registered prospectively.

RESULTS

Seventy-four patients received 78 operations, 21 (26.9%) of the 78 operations were minimally invasive. Seven of 16 tumor biopsies (43.8%) and 9 of 57 tumor resections (15.8%) were performed using MIS, which was also exclusively used for diagnostic interventions. Conversions to standard techniques only occurred in 5 of 9 tumor resections. No major complications were encountered in the MIS group.

CONCLUSIONS

MIS was practical in every fourth patient in our experience so far. It proved to be an excellent approach in diagnostic interventions and tumor biopsies, whereas efficacy is limited in tumor resections. Further factors (tumor recurrence, trocar site recurrence, tumor growth, and dissemination after CO(2) insufflation) have to be evaluated. Our data encourage the continuation of the study.

Mesenterico-left portal vein bypass in children with congenital extrahepatic portal vein thrombosis: a unique curative approach

OBJECTIVES

Current management of extrahepatic portal vein thrombosis (EPVT) comprises endoscopic eradication therapy of esophageal varices and conventional shunt surgery. The authors have used the novel technique of mesenterico-left portal bypass (Rex shunt) in seven children with symptomatic EPVT, and report their results here.

METHODS

Median age of the children was 12 years (range, 2-16 years). All children had portal hypertension with hypersplenism and recurrent bleeding from esophageal varices. Furthermore, one patient suffered from a severe hepatopulmonary syndrome. Preoperative evaluation included liver function tests, liver biopsy, hepatic duplex ultrasonography, and radiologic evaluation of the intrahepatic and extrahepatic vascular anatomy. The internal jugular vein was used as vein graft in all patients.

RESULTS

Median follow-up period was 15 months (range, 3-28 months). Ultrasound scans revealed sufficient perfusion in all shunts (median, 35 cm/s; range, 28-60 cm/s). The intrahepatic portal perfusion in segment 4 improved from a median of 6 cm/s before surgery to 18 cm/s postoperatively. The platelet count increased within 3 months from a mean of 50,625/microL to 137,750/microL. The clinical signs of hypoxemia in the child with hepatopulmonary syndrome disappeared within 6 months.

CONCLUSIONS

In accordance with the limited experience published by others, the authors' data confirmed the mesenterico-portal Rex shunt as the therapy of choice for children with EPVT. Furthermore, this report is the first to show that a hepatopulmonary syndrome can be abolished by mesenterico-portal Rex shunt.

MDR1 modulators improve the chemotherapy response of human hepatoblastoma to doxorubicin in vitro

PURPOSE

P-glycoprotein, a membrane efflux pump encoded by the MDR1 gene, plays an important role in the development of multidrug resistance in human hepatoblastoma (HB). Chemosensitizers antagonize the efflux action of P-glycoprotein. This study investigates the effects of 3 chemosensitizers (the cyclosporin analogue SDZ PSC 833 (PSC 833), the acridone carboxamide derivative GG 918, and verapamil) on the chemotherapy of HB in vitro.

METHODS

The doxorubicin (DOXO) concentration that produces 50% growth inhibition (IC50) in a HB cell line was determined and additional effects of PSC 833, GG 918, and verapamil were investigated in a cytotoxicity assay. The MDR1 gene expression after treatment was determined in a semiquantitative reverse transcription polymerase chain reaction approach.

RESULTS

The IC50 of DOXO is 2.5 microg/mL, 0.61 microg/mL for DOXO + PSC 833, 1.17 microg/mL for DOXO + verapamil, and 1.47 microg/mL for DOXO + GG 918. In combination with DOXO, cell growth was inhibited 4.1-fold by PSC 833, 2.1-fold by verapamil, and 1.9-fold by GG 918. The MDR1 gene expression was enhanced significantly in all treated cells, with and without modulator.

CONCLUSIONS

MDR1 modulators significantly improve the response of HB to DOXO in vitro. The combination of anticancer agents and MDR1 modulators might be a possible contribution to overcome multidrug resistance in HB.

The role of the MDR1 gene in the development of multidrug resistance in human hepatoblastoma: clinical course and in vivo model

BACKGROUND

The P-glyprotein (P-gp), which is a membrane channel encoded by the MDR1 gene, represents a possible explanation for multidrug resistance in human hepatoblastoma (HB). P-gp shows up-regulation in tumor cells after chemotherapy; however, to date, its exact role in HB has not been described. The authors investigated the role of the MDR1 gene in the clinical course of patients with HB and in an in vivo model of HB. They also studied the effects of the MDR1 antagonizer PSC 833 on chemotherapy in mice xenotransplanted with HB.

METHODS

Resected tumor specimens, including both primary tumors and recurrent tumors, from a child suffering from HB were investigated histologically. Cell suspensions from the originally removed tumor were incorporated subcutaneously into nude mice. Animals were treated with cisplatin (CDDP) plus PSC 833. MDR1 gene expression levels in the different resected tumors from the patient and in the xenotransplants after treatment were determined with polymerase chain reaction analysis.

RESULTS

MDR1 gene expression was increased in the patient's tumors after every course of chemotherapy from 30% to > 190%. In the xenotransplants, MDR1 gene expression was enhanced significantly after chemotherapy (P(CDDP) = 0.008; P(CDDP+PSC) = 0.002). Tumor volumes (P < 0.001) and serum alpha-fetoprotein levels (P = 0.0002) were significantly lower in the animals that were treated with CDDP + PSC compared with the animals that were treated with CDDP alone.

CONCLUSIONS

The current results suggest that MDR1 gene expression and P-gp are a potential mechanism of drug resistance in HB. The chemosensitizer PSC 833 significantly improved the effects of chemotherapy in animals xenotransplanted with HB. These data encourage further studies concerning the role of chemosensitizers in overcoming multidrug resistance in patients with HB.

Cystic echinococcosis with perforation into the biliary tract in an eight-year-old girl

Cystic echinococcosis (CE) is a zoonotic infection caused by echinococcus granulosus and is still frequent in endemic areas. CE is predominantly localised in the liver. The therapy of choice is the surgical sanitation of the lesions, increasingly through interventional procedures such as percutaneous punctation of the cysts, aspiration of the cystic fluid, instillation of a protoscolicidal solution and reaspiration of this solution (PAIR). However, in some cases, such as perforation into the biliary tract, PAIR is not feasible. We report on an eight-year-old girl who suffered from CE with perforation of one cyst into the biliary tract. The diagnosis was confirmed by ERCP and cholangioscopy and a right hemihepatectomy was performed. The girl received adjuvant chemotherapy with albendazol perioperatively and is still asymptomatic with no indications of disease 10 months after the operation.

Congenital adrenal hyperplasia associated with maternal pregnancy luteoma and the Antley-Bixler syndrome

The authors report on a child with indifferent external genitalia consisting of severe micropenis with penile urethra leading to the tip of the glans and bilateral cryptorchidism. Diagnostic workup findings showed a female karyotype, homozygous 21-hydroxylase deficiency, and excessive testosterone exposure prenatally as a consequence of maternal pregnancy luteoma, altogether causing this unusual phenotype. In addition, the girl suffered from skeletal anomalies consistent with the diagnosis of Antley-Bixler syndrome. Our case shows that, although the association of congenital adrenal hyperplasia with other syndromes is rare, and even if other possible reasons for in utero virilization are present, complete diagnostic workup including karyotyping and hormonal status should be done in all patients with ambiguous genitalia, especially in cases of an unusual phenotype. The authors report on the diagnostic procedures and discuss the surgical approach in this particular case, never described before in the literature.