Omission of adjuvant chemotherapy in patients with completely necrotic Wilms tumor stage I and radiotherapy in stage III: The 30-year SIOP-RTSG experience

BACKGROUND

Completely necrotic Wilms tumor (CN-WT) following preoperative chemotherapy has been regarded as low-risk WT since the International Society of Paediatric Oncology (SIOP) 93-01 study, and patients have been treated with reduced postoperative therapy. The aim of the study was to evaluate whether the omission of adjuvant chemotherapy in patients with localized CN-WT stage I and radiotherapy in stage III was safe.

PATIENTS AND METHODS

The retrospective observational study of outcomes of patients diagnosed with localized CN-WT on central pathology review and treated according to the SIOP 93-01 and SIOP-WT-2001 protocols (1993-2022).

RESULTS

There were 125 patients with localized CN-WT: 90 with stage I, 10 with stage II, and 25 with stage III. Sixty-two of 125 (49.6%) patients had a discrepant diagnosis and/or staging between the institutional pathologist and central pathology review. In the group of 90 patients with stage I, postoperative chemotherapy was not given to 41 (46%) patients, whereas 49 patients received postoperative chemotherapy-in the latter group, two patients relapsed, and one of them died. One stage I and one stage II patient developed chemotherapy-induced toxicity and died. Nineteen of 25 patients with stage III received no flank radiotherapy. No stage III patient relapsed or died. The overall 5-year event-free survival (EFS) estimate for the entire cohort (stages I-III) was 96.8% [95% confidence interval, CI: 93.6%-99.6%] and the overall survival (OS) was 97.6% [95% CI: 95.0-100%]. The EFS and OS were 97% and 98%, respectively, for stage I, and 100% for stage III.

CONCLUSION

Omission of postoperative chemotherapy for patients with CN-WT stage I, and radiotherapy for stage III is safe. Rapid central pathology review is required to assign appropriate treatment and avoid treatment-related side effects.

Fusion-negative rhabdomyosarcoma 3D organoids to predict effective drug combinations: A proof-of-concept on cell death inducers

Rhabdomyosarcoma (RMS) is the main form of pediatric soft-tissue sarcoma. Its cure rate has not notably improved in the last 20 years following relapse, and the lack of reliable preclinical models has hampered the design of new therapies. This is particularly true for highly heterogeneous fusion-negative RMS (FNRMS). Although methods have been proposed to establish FNRMS organoids, their efficiency remains limited to date, both in terms of derivation rate and ability to accurately mimic the original tumor. Here, we present the development of a next-generation 3D organoid model derived from relapsed adult and pediatric FNRMS. This model preserves the molecular features of the patients' tumors and is expandable for several months in 3D, reinforcing its interest to drug combination screening with longitudinal efficacy monitoring. As a proof-of-concept, we demonstrate its preclinical relevance by reevaluating the therapeutic opportunities of targeting apoptosis in FNRMS from a streamlined approach based on transcriptomic data exploitation.

International Comparisons of Clinical Demographics and Outcomes in the International Society of Pediatric Oncology Wilms Tumor 2001 Trial and Study

International comparisons of patient demographics, tumor characteristics, and survival can shed light on areas for health care system improvement. The International Society of Pediatric Oncology Wilms Tumor 2001 trial/study registered patients through national clinical study groups in Western Europe and Brazil. This retrospective post hoc analysis of the International Society of Pediatric Oncology Wilms Tumor 2001 database aims to make visible and suggest reasons for any variations in outcomes.

International variation in Wilms tumor survival parallels disease burden at diagnosis.

High-dose chemotherapy followed by autologous stem cell rescue in Wilms tumors: French report on toxicity and efficacy

BACKGROUND

Heterogeneous data have been reported on high-dose chemotherapy (HDCT) with autologous stem cell rescue (ASCR) in Wilms tumors (WTs). We aimed to define its safety and efficacy in the French cohort, and to compare this management to current international recommendations.

METHODS

Data prospectively collected from children, adolescents, and young adults with WT treated with HDCT/ASCR between 2000 and 2016 in French centers were retrospectively analyzed. Toxicity was reported according to CTCAE v4.03.

RESULTS

Fifty-four patients received HDCT/ASCR (first line, n = 13; recurrence, n = 41). Their median age at the time of ASCR was 5.3 years (range 2.2-21.6). Main nonhematological acute grades 3-4 toxicities were digestive and renal. No significant difference of toxicity rate was observed among HDCT regimens and schedules. Two patients died shortly after ASCR (renal and multiorgan failure), and one heavily pretreated patient died of late respiratory failure. The selection criteria applied to define those patients eligible for HDCT/ASCR retrospectively matched to those currently used in the International Society of Pediatric Oncology (SIOP) UMBRELLA protocol for 38 patients, with encouraging survival rates compared to published data. The objective response rate to HDCT was 21%, with a disease control rate after HDCT of 85%. After a median follow-up of 7 years, the 5-year event-free survival (EFS) and overall survival (OS) were 54% (95% CI: 32%-76%) and 62% (95% CI: 31%-82%) for frontline patients, and 57% (95% CI: 39%-71%) and 69% (95% CI: 52%-81%) at recurrence.

CONCLUSION

HDCT was feasible and showed encouraging results in well-defined settings. Data from the current prospective protocol will help to better evaluate HDCT impact on survival.

Clinical characteristics and outcomes of children with WAGR syndrome and Wilms tumor and/or nephroblastomatosis: The 30-year SIOP-RTSG experience

BACKGROUND

WAGR syndrome (Wilms tumor, aniridia, genitourinary anomalies, and range of developmental delays) is a rare contiguous gene deletion syndrome with a 45% to 60% risk of developing Wilms tumor (WT). Currently, surveillance and treatment recommendations are based on limited evidence.

METHODS

Clinical characteristics, treatments, and outcomes were analyzed for patients with WAGR and WT/nephroblastomatosis who were identified through International Society of Pediatric Oncology Renal Tumor Study Group (SIOP-RTSG) registries and the SIOP-RTSG network (1989-2019). Events were defined as relapse, metachronous tumors, or death.

RESULTS

Forty-three patients were identified. The median age at WT/nephroblastomatosis diagnosis was 22 months (range, 6-44 months). The overall stage was available for 40 patients, including 15 (37.5%) with bilateral disease and none with metastatic disease. Histology was available for 42 patients; 6 nephroblastomatosis without further WT and 36 WT, including 19 stromal WT (52.8%), 12 mixed WT (33.3%), 1 regressive WT (2.8%) and 2 other/indeterminable WT (5.6%). Blastemal type WT occurred in 2 patients (5.6%) after prolonged treatment for nephroblastomatosis; anaplasia was not reported. Nephrogenic rests were present in 78.9%. Among patients with WT, the 5-year event-free survival rate was 84.3% (95% confidence interval, 72.4%-98.1%), and the overall survival rate was 91.2% (95% confidence interval, 82.1%-100%). Events (n = 6) did not include relapse, but contralateral tumor development (n = 3) occurred up to 7 years after the initial diagnosis, and 3 deaths were related to hepatotoxicity (n = 2) and obstructive ileus (n = 1).

CONCLUSIONS

Patients with WAGR have a high rate of bilateral disease and no metastatic or anaplastic tumors. Although they can be treated according to existing WT protocols, intensive monitoring of toxicity and surveillance of the remaining kidney(s) are advised.

LAY SUMMARY

WAGR syndrome (Wilms tumor, aniridia, genitourinary anomalies, and range of developmental delays) is a rare genetic condition with an increased risk of developing Wilms tumor. In this study, 43 patients with WAGR and Wilms tumor (or Wilms tumor precursor lesions/nephroblastomatosis) were identified through the international registry of the International Society of Pediatric Oncology Renal Tumor Study Group (SIOP-RTSG) and the SIOP-RTSG network. In many patients (37.5%), both kidneys were affected. Disease spread to other organs (metastases) did not occur. Overall, this study demonstrates that patients with WAGR syndrome and Wilms tumor can be treated according to existing protocols. However, intensive monitoring of treatment complications and surveillance of the remaining kidney(s) are advised.

Embryonal rhabdomyosarcoma completely resected at diagnosis: The European paediatric Soft tissue sarcoma Study Group RMS2005 experience

BACKGROUND

Rhabdomyosarcoma (RMS) is the most common form of soft tissue sarcoma in children. We report the results of the European paediatric Soft tissue sarcoma Study Group (EpSSG) RMS 2005 study, which prospectively evaluated the reduction of chemotherapy in patients with embryonal RMS (ERMS) after initial surgery.

METHODS

Between October 2005 and December 2016, all patients with localised ERMS with an initial microscopically complete resection (IRS group I) with lymph node-negative (N0) were prospectively enrolled in the low-risk (n = 70, subgroup A; age < 10 years and tumour size ≤ 5 cm) or standard-risk group (n = 108, subgroup B; age ≥ 10 years or tumour size > 5 cm. Subgroup A received 8 courses of vincristine and dactinomycin (VA) for 22 weeks; subgroup B received 4 courses of VA with ifosfamide (IVA) and 5 courses of VA for 25 weeks.

RESULTS

The 5-year event-free survival (EFS) and overall survival (OS) were 90.8% (95% confidence interval [CI]: 85.0-94.4) and 95.7% (95% CI: 90.5-98.1), respectively (n = 178). The EFS and OS were 95.5% (95% CI: 86.8-98.5) and 100% (subgroupA), and 87.8% (95% CI: 79.3-93.0) and 93.0% (95% CI: 84.8-96.8)(subgroup B), respectively. Bearman stage 2 veno-occlusive disease (VOD) occurred in 4 very young patients.

CONCLUSION

VA treatment for 8 courses was effective and well tolerated by the subgroup of patients with low-risk ERMS (group A). Four courses of IVA and 5 courses of VA instead of 9 courses of IVA also has very good results. Careful monitoring for liver toxicity is important in very young patients. European union drug regulating authorities clinical trials EUDRACT No. 2005-000217-35.

Tumor Molecular Profiling: Pediatric Results of the ProfiLER Study

PURPOSE

The Program to Establish the Genetic and Immunologic Profile of Patient's Tumor for All Types of Advanced Cancer study (ClinicalTrials.gov identifier: NCT01774409) analyzed the genome of refractory cancers to identify a potential molecular-based recommended therapy (MBRT). The objectives of the pediatric substudy were to describe the incidence of genomic mutations, the MBRT, and the treatments undertaken with a molecular-targeted agent in a pediatric cohort.

METHODS

The tumor genome was analyzed within a 69-gene next-generation sequencing panel and an array comparative genomic hybridization assay. The results were evaluated by a multidisciplinary molecular board, and the targeted therapies were provided in the setting of a clinical trial or through compassionate use programs, when indicated.

RESULTS

Between November 2013 and June 2017, 50 patients younger than 19 years who were treated for a high-risk or relapsing tumor were included. Sarcomas (n = 24; 47%), CNS tumors (n = 14; 29%), and neuroblastomas (n = 5; 10%) were the most frequent tumor subtypes. Seven patients (14%) were excluded because no DNA could be recovered. Among the 43 remaining patients, 10 exhibited at least one targetable genomic alteration. Ultimately, four patients (8%) were treated with the recommended targeted therapy.

CONCLUSION

The results of this study confirm treatment with a targeted therapy for pediatric patients with cancer is still limited at present, as also is reported for adults.

Wilms tumors and their precursors: Radiological diagnosis versus histology

The radiological distinction of Wilms tumor (WT) nodules from nephrogenic rests (NR) in patients with multifocal unilateral WT or bilateral disease is challenging. The study aims to compare the radiology assessment of kidney nodules with their final histology in 48 patients. The final histology of 118 nodules corresponded to the initial radiological diagnosis while 40 (25%) nodules were misdiagnosed, 20 being initially diagnosed WT on imaging were proved to be NR at histology. The size of nodules at diagnosis might help to distinguish WT from NR before surgery. Homogeneity did not seem to be a key feature.

Low expression of ANT1 confers oncogenic properties to rhabdomyosarcoma tumor cells by modulating metabolism and death pathways

Rhabdomyosarcoma (RMS) is the most frequent form of pediatric soft-tissue sarcoma. It is divided into two main subtypes: ERMS (embryonal) and ARMS (alveolar). Current treatments are based on chemotherapy, surgery, and radiotherapy. The 5-year survival rate has plateaued at 70% since 2000, despite several clinical trials. RMS cells are thought to derive from the muscle lineage. During development, myogenesis includes the expansion of muscle precursors, the elimination of those in excess by cell death and the differentiation of the remaining ones into myofibers. The notion that these processes may be hijacked by tumor cells to sustain their oncogenic transformation has emerged, with RMS being considered as the dark side of myogenesis. Thus, dissecting myogenic developmental programs could improve our understanding of RMS molecular etiology. We focused herein on ANT1, which is involved in myogenesis and is responsible for genetic disorders associated with muscle degeneration. ANT1 is a mitochondrial protein, which has a dual functionality, as it is involved both in metabolism via the regulation of ATP/ADP release from mitochondria and in regulated cell death as part of the mitochondrial permeability transition pore. Bioinformatics analyses of transcriptomic datasets revealed that ANT1 is expressed at low levels in RMS. Using the CRISPR-Cas9 technology, we showed that reduced ANT1 expression confers selective advantages to RMS cells in terms of proliferation and resistance to stress-induced death. These effects arise notably from an abnormal metabolic switch induced by ANT1 downregulation. Restoration of ANT1 expression using a Tet-On system is sufficient to prime tumor cells to death and to increase their sensitivity to chemotherapy. Based on our results, modulation of ANT1 expression and/or activity appears as an appealing therapeutic approach in RMS management.

Liver metastasis at diagnosis in children with nephroblastoma enrolled in SIOP2001 protocol: A French multicentric study

BACKGROUND

Liver metastases are rare in children with Wilms tumor (WT), and their impact on the outcome is unclear.

PATIENTS AND METHODS

The French cohort of patients with WT presenting liver metastases at diagnosis and enrolled in the International Society of Pediatric Oncology (SIOP) 2001 study was reviewed.

RESULTS

From 2002 to 2012, 906 French patients were enrolled in the SIOP2001 trial. Among them, 131 (14%) presented with stage IV WT and 18 (1.9%) had liver metastases at diagnosis. Isolated liver metastases were displayed in four of them. After preoperative chemotherapy, persistent liver disease was reported in 14/18 patients, and 13 of them underwent metastasectomy after nephrectomy. In resected liver lesions, the same histology of the primary tumor was reported for three patients, blastemal cells without anaplasia were identified in one patient with DA-WT, and post-chemotherapy necrosis/fibrosis was identified for the other 10 patients. For the four patients who had liver and lung surgery, both sites had nonviable cells with post-chemotherapy necrosis/fibrosis. Six patients had hepatic radiotherapy. Sixteen patients achieved primary complete remission and were alive at the last follow-up (median follow-up: 6.4 years). The only two deceased patients presented diffuse anaplasia histology. The five-year EFS and OS were 83% (60%-94%) and 88% (66%-97%), respectively.

CONCLUSION

Liver involvement does not appear to be an adverse prognostic factor in metastatic WT. The role of hepatic surgery and radiotherapy remains unclear, and should be carefully considered in case of persistent liver metastases, according to histology and radiological response to other metastatic sites.

Environmental exposures related to parental habits in the perinatal period and the risk of Wilms' tumor in children

INTRODUCTION

Wilms' tumor is the most frequently diagnosed renal tumor in children. Little is known about its etiology. The aim of this study was to investigate the potential role of specific exposures related to parental habits such as parental smoking, maternal alcohol consumption and the use of household pesticides during pregnancy.

METHODS

The ESTELLE study was a nationwide case-control study that included 117 Wilms' tumor cases and 1100 control children from the general French population, frequency-matched by age and gender. Unconditional logistic regression was used to estimate odds ratios and 95 % confidence intervals.

RESULTS

After controlling for matching variables and potential confounders, the maternal use of any type of pesticide during pregnancy was associated with the risk of Wilms' tumor in children (OR 1.6 [95 % CI 1.1-2.3]). Insecticides were the most commonly reported type of pesticide and there was a positive association with their use (OR 1.7 [95 % CI 1.1-2.6]. The association was stronger when they were used more often than once a month (OR 1.9 [95 % CI 1.2-3.0]. Neither maternal smoking during pregnancy nor paternal smoking during preconception/pregnancy was associated with a risk of Wilms' tumor (ORs 1.1[95 % CI 0.7-1.8] and 1.1 [95 % CI 0.7-1.7], respectively). No association was observed with maternal alcohol intake during pregnancy (OR 1.2 [95 % CI 0.8-2.0]).

CONCLUSION

Our findings suggest an association between the maternal use of household pesticides during pregnancy and the risk of Wilms' tumor.

Maternal and perinatal characteristics, congenital malformations and the risk of wilms tumor: the ESTELLE study

PURPOSE

Wilms tumor (WT), or nephroblastoma, is an embryonic tumor that constitutes the most common renal tumor in children. Little is known about the etiology of WT. The aim of this study was to investigate whether maternal or perinatal characteristics were associated with the risk of WT.

METHODS

The ESTELLE study is a national-based case-control study that included 117 cases of WT and 1,100 controls younger than 11 years old. The cases were children diagnosed in France in 2010-2011 and the controls were frequency matched with cases by age and gender. The mothers of case and control children responded to a telephone questionnaire addressing sociodemographic and perinatal characteristics, childhood environment, and lifestyle. Unconditional logistic regression models adjusted on potential cofounders were used to estimate the odds ratios (OR) and their confidence intervals (95% CI).

RESULTS

High birth weight and the presence of congenital malformation were associated with WT (OR 1.9 [95% CI 1.0-3.7] and OR 2.5 [95% CI 1.1-5.8], respectively). No association with breastfeeding or folic acid supplementation was observed.

CONCLUSIONS

Although potential recall bias cannot be excluded, our findings reinforce the hypothesis that high birth weight and the presence of congenital malformation may be associated with an increased risk of WT. Further investigations are needed to further elucidate the possible role of maternal characteristics in the etiology of WT.

Outcome of patients with stage IV high-risk Wilms tumour treated according to the SIOP2001 protocol: A report of the SIOP Renal Tumour Study Group

INTRODUCTION

High-risk (HR) metastatic (stage IV) Wilms tumours (WTs) have a particular poor outcome.

METHODS

Here, we report the results of HR (diffuse anaplastic [DA] or blastemal type [BT]) stage IV WT treated patients according to the HR arm in the SIOP2001 prospective study.

RESULTS

From January 2002 to August 2014, 3559 patients with WT were included in the SIOP2001 trial. Among the 525 patients (15%) with metastatic WT, 74 (14%) had stage IV HR-WT. The median age at diagnosis was 5.5 years (range: 1.4-18.3). Thirty-four patients (47%) had BT-WT and 40 (53%) had DA-WT. Five-year event-free survival rates were 44 ± 17% and 28 ± 15% for BT-WT and DA-WT, respectively (p = 0.09). Five-year overall survival rates were 53 ± 17% and 29 ± 16% for BT-WT and DA-WT, respectively (p = 0.03). Metastatic complete response after preoperative treatment was significantly associated with outcome in univariate and multivariate analyses (hazards ratio = 0.3; p = 0.01). Postoperative radiotherapy of metastatic sites might also be beneficial. Forty-three of 74 patients experienced a relapse or progression predominantly in the lungs (80%). The median time to relapse/progression after diagnosis was 7.3 months (range: 1.6-33.3) and 4.9 months (range: 0.7-28.4) for BT-WT and DA-WT, respectively (p = 0.67). This is the first prospective evidence of inferior survival of stage IV BT-WT as compared with historical intermediate-risk WT. Survival of patients with stage IV DA-WT has not improved compared to the previous SIOP93-01 study.

CONCLUSION

These results call for new treatment approaches for patients with HR stage IV WT.

Is radiotherapy required in first-line treatment of stage I diffuse anaplastic Wilms tumor? A report of SIOP-RTSG, AIEOP, JWiTS, and UKCCSG

BACKGROUND

As a significant proportion of relapses occurred in the tumor bed or abdomen on patients with the fifth National Wilms Tumor Study stage I anaplastic Wilms tumor (WT), flank radiotherapy was added for stage I anaplastic WT in the subsequent study of the Children's Oncology Group (AREN0321). Preliminary results revealed reduction of relapse rate and improved survival. In cases treated with preoperative chemotherapy, such as in International Society of Pediatric Oncology (SIOP), the value of radiotherapy has never been studied. The aim of this observational study is to describe the pattern of recurrence and survival of patients with stage I diffuse anaplastic WT (DAWT) after induction chemotherapy.

METHODS

Retrospective data analysis of the pattern of relapse and survival of all patients with stage I DAWT were included in recent SIOP, L'Associazone Italiana Ematologica Oncologia Pediatrica (AIEOP), Japan Wilms Tumor Study Group (JWiTS), United Kingdom Children's Cancer Study Group (UKCCSG) renal tumor registries. Postoperative treatment consisted of actinomycin D, vincristine, and doxorubicin for 28 weeks without local irradiation.

RESULTS

One hundred nine cases with stage I DAWT were identified, of which 95 cases received preoperative chemotherapy. Of these, seven patients underwent preoperative true-cut biopsy. Sixteen of the 95 patients relapsed (17%), six locally, four at distant site, and six combined, and all treated according to SIOP 2001 relapse protocol, which resulted in a 5-year overall survival of 93%.

CONCLUSION

Despite 13% locoregional relapse rate, an excellent rescue rate was achieved after salvage treatment, in patients with stage I DAWT whose first-line treatment comprised three-drug chemotherapy (including doxorubicin), without flank irradiation. Therefore, we continue not to advocate the use of radiotherapy in first-line treatment after preoperative chemotherapy in stage I DAWT in the next SIOP protocol.

Vinorelbine and continuous low-dose cyclophosphamide as maintenance chemotherapy in patients with high-risk rhabdomyosarcoma (RMS 2005): a multicentre, open-label, randomised, phase 3 trial

BACKGROUND

For more than three decades, standard treatment for rhabdomyosarcoma in Europe has included 6 months of chemotherapy. The European paediatric Soft tissue sarcoma Study Group (EpSSG) aimed to investigate whether prolonging treatment with maintenance chemotherapy would improve survival in patients with high-risk rhabdomyosarcoma.

METHODS

RMS 2005 was a multicentre, open-label, randomised, controlled, phase 3 trial done at 102 hospitals in 14 countries. We included patients aged 6 months to 21 years with rhabdomyosarcoma who were considered to be at high risk of relapse: those with non-metastatic incompletely resected embryonal rhabdomyosarcoma occurring at unfavourable sites with unfavourable age (≥10 years) or tumour size (>5 cm), or both; those with any non-metastatic rhabdomyosarcoma with nodal involvement; and those with non-metastatic alveolar rhabdomyosarcoma but without nodal involvement. Patients in remission after standard treatment (nine cycles of ifosfamide, vincristine, dactinomycin with or without doxorubicin, and surgery or radiotherapy, or both) were randomly assigned (1:1) to stop treatment or continue maintenance chemotherapy (six cycles of intravenous vinorelbine 25 mg/m2 on days 1, 8, and 15, and daily oral cyclophosphamide 25 mg/m2, on days 1-28). Randomisation was done by use of a web-based system and was stratified (block size of four) by enrolling country and risk subgroup. Neither investigators nor patients were masked to treatment allocation. The primary outcome was disease-free survival in the intention-to-treat population. Secondary outcomes were overall survival and toxicity. This trial is registered with EudraCT, number 2005-000217-35, and ClinicalTrials.gov, number NCT00339118, and follow-up is ongoing.

FINDINGS

Between April 20, 2006, and Dec 21, 2016, 371 patients were enrolled and randomly assigned to the two groups: 186 to stop treatment and 185 to receive maintenance chemotherapy. Median follow-up was 60·3 months (IQR 32·4-89·4). In the intention-to-treat population, 5-year disease-free survival was 77·6% (95% CI 70·6-83·2) with maintenance chemotherapy versus 69·8% (62·2-76·2) without maintenance chemotherapy (hazard ratio [HR] 0·68 [95% CI 0·45-1·02]; p=0·061), and 5-year overall survival was 86·5% (95% CI 80·2-90·9) with maintenance chemotherapy versus 73·7% (65·8-80·1) without (HR 0·52 [95% CI 0·32-0·86]; p=0·0097). Toxicity was manageable in patients who received maintenance chemotherapy: 136 (75%) of 181 patients had grade 3-4 leucopenia, 148 (82%) had grade 3-4 neutropenia, 19 (10%) had anaemia, two (1%) had thrombocytopenia, and 56 (31%) had an infection. One (1%) patient had a grade 4 non-haematological toxicity (neurotoxicity). Two treatment-related serious adverse events occurred: one case of inappropriate antidiuretic hormone secretion and one of a severe steppage gait with limb pain, both of which resolved.

INTERPRETATION

Adding maintenance chemotherapy seems to improve survival for patients with high-risk rhabdomyosarcoma. This approach will be the new standard of care for patients with high-risk rhabdomyosarcoma in future EpSSG trials.

FUNDING

Fondazione Città della Speranza, Association Léon Berard Enfant Cancéreux, Clinical Research Hospital Program (French Ministry of Health), and Cancer Research UK.

Repurposing rotavirus vaccines for intratumoral immunotherapy can overcome resistance to immune checkpoint blockade

Although immune checkpoint-targeted therapies are currently revolutionizing cancer care, only a minority of patients develop durable objective responses to anti-PD-1, PD-L1, and CTLA-4 therapy. Therefore, new therapeutic interventions are needed to increase the immunogenicity of tumors and overcome the resistance to these immunotherapies. Oncolytic properties of common viruses can be exploited for the priming of antitumor immunity, and such oncolytic viruses are currently in active clinical development in combination with immune checkpoint-targeted therapies. However, the routine implementation of these therapies is limited by their manufacturing constraints, the risk of exposure of clinical staff, and the ongoing regulations on genetically modified organisms. We sought to determine whether anti-infectious disease vaccines could be used as a commercially available source of immunostimulatory agents for cancer immunotherapy. We found that rotavirus vaccines have both immunostimulatory and oncolytic properties. In vitro, they can directly kill cancer cells with features of immunogenic cell death. In vivo, intratumoral rotavirus therapy has antitumor effects that are dependent on the immune system. In several immunocompetent murine tumor models, intratumoral rotavirus overcomes resistance to and synergizes with immune checkpoint-targeted therapy. Heat- and UV-inactivated rotavirus lost their oncolytic activity but kept their synergy with immune checkpoint-targeted antibodies through the up-regulation of the double-stranded RNA receptor retinoic acid-induced gene 1 (RIG-I). Rotavirus vaccines are clinical-grade products used in pediatric and adult populations. Therefore, in situ immunization strategies with intratumoral-attenuated rotavirus could be implemented quickly in the clinic.

Prognostic significance of age in 5631 patients with Wilms tumour prospectively registered in International Society of Paediatric Oncology (SIOP) 93-01 and 2001

BACKGROUND

To enhance risk stratification for Wilms tumour (WT) in a pre-operative chemotherapy setting, we explored the prognostic significance and optimal age cutoffs in patients treated according to International Society of Paediatric Oncology Renal Tumour Study Group (SIOP-RTSG) protocols.

METHODS

Patients(6 months-18 years) with unilateral WT were selected from prospective SIOP 93-01 and 2001 studies(1993-2016). Martingale residual analysis was used to explore optimal age cutoffs. Outcome according to age was analyzed by uni- and multivariable analysis, adjusted for sex, biopsy(yes/no), stage, histology and tumour volume at surgery.

RESULTS

5631 patients were included; median age was 3.4 years(IQR: 2-5.1). Estimated 5-year event-free survival (EFS) and overall survival (OS) were 85%(95%CI 83.5-85.5) and 93%(95%CI 92.0-93.4). Martingale residual plots detected no optimal age cutoffs. Multivariable analysis showed lower EFS with increasing age(linear trend P<0.001). Using previously described age categories, EFS was lower for patients aged 2-4(HR 1.34, P = 0.02), 4-10(HR 1.83, P<0.0001) and 10-18 years(HR 1.74, P = 0.01) as compared to patients aged 6 months-2 years. OS was lower for patients 4-10 years(HR 1.67, P = 0.01) and 10-18 years(HR 1.87, P = 0.04), but not for 2-4 years(HR 1.29, P = 0.23). Higher stage, histological risk group and tumour volume were independent adverse prognostic factors.

CONCLUSION

Although optimal age cutoffs could not be identified, we demonstrated the prognostic significance of age as well as previously described cutoffs for EFS (2 and 4 years) and OS (4 years) in children with WT treated with pre-operative chemotherapy. These findings encourage the consideration of age in the design of future SIOP-RTSG protocols.

Outcome of localized liver-bile duct rhabdomyosarcoma according to local therapy: A report from the European Paediatric Soft-Tissue Sarcoma Study Group (EpSSG)-RMS 2005 study

OBJECTIVES

To evaluate the impact of local therapies on the outcome of patients with liver-bile duct rhabdomyosarcoma (LBDRMS).

METHODS

Data of 30 patients included in the EpSSG-RMS 2005 study were analyzed.

RESULTS

The median age at diagnosis was 3 years (11 months-8 years). All patients had non-alveolar histology. Fifteen patients had a tumor > 5 cm and six had enlarged regional lymph nodes on imaging. Eight patients (27%) had primary surgery (1 R0). Six of them received external beam radiotherapy (EBRT). All are in first complete remission (CR1) except one (R1, EBRT⁺ , local relapse, death). Six patients (20%) received EBRT without surgery: one had local relapse and died. Sixteen patients (53%) underwent delayed surgery, with 12 achieving R0 margins, which were higher than those in the primary surgery group (P = 0.003). Three patients with R0 margins received EBRT; one had a metastatic relapse and died. Nine patients with R0 resection did not receive EBRT, three relapsed locally (two deaths). Four R1 patients received additional EBRT without relapses. Local relapse occurred in two among 19 patients with EBRT and three among 11 without EBRT (P = 0.326). At a median follow-up of 61 months (48-84 months), five patients died; all had a tumor size > 5 cm (P = 0.01). The five-year overall survival was 85% (95% CI, 65-94), and event-free survival was 76% (95% CI, 54-89).

CONCLUSION

This analysis did not show any significant difference in outcome between irradiated and nonirradiated patients. Local relapse in LBDRMS is related to initial tumor size and is often fatal.

Evaluation of needle biopsy as a potential risk factor for local recurrence of Wilms tumour in the SIOP WT 2001 trial

RATIONALE

The impact of biopsying Wilms tumour (WT) at diagnosis on assigning the tumour stage and recommended treatment remains controversial. To address this important question, we analysed the potential association of all types of biopsy with local recurrence in patients treated in the SIOP WT 2001 trial, where needle biopsy was permitted without 'upstaging' the tumour to stage III. Only open biopsy required treatment as stage III.

METHODS

Among 2971 patients with unilateral WT (stages I-IV), 420 relapsed (139 local). Risk factors for recurrence were analysed by Cox proportional hazard methods.

RESULTS

Biopsy was performed in 969 of 2971 (33%) patients (64% cutting needle, 30% fine needle aspiration [FNA] and 6% open biopsy). Biopsied patients were older, with larger tumours and a greater proportion with high-risk histology. In multivariate analysis that included all factors associated with local recurrence in univariate analysis, only high-risk histology (hazard ratio [HR] = 2.32; 95% confidence interval [CI]: 1.58-3.42, p=<0.0001), age≥2 years (HR = 2.24; 95% CI: 1.22-4.09, p = 0.01) and preoperative tumour volume (HR = 1.07 per 100 ml; 95% CI: 1.02-1.12, p = 0.01) were significant. The HR for the association of local recurrence and event-free and overall survival with biopsy was not significant (HR = 1.4; 95% CI: 0.9-2.17, p = 0.13; HR = 1.1; 95% CI: 0.85-1.42, p = 0.46 and HR = 1.13; 95% CI: 0.79-1.62, p = 0.51, respectively). These results were not materially different whether FNA or open biopsy were included in the biopsy group or not.

CONCLUSIONS

This post hoc analysis provides some reassurance that needle biopsy is not an independent adverse factor for either local recurrence or survival after adjustment for all relevant risk factors. Needle biopsy should not be an automatic criterion to 'upstage' WT.

English Translation of M. Bérard: Tumeur Embryonnaire Du Muscle Strié. [Embryonal Tumor of Striated Muscle]. Lyon Med 1894; 77: 52

We have chosen to translate what we believe to be the first publication of a well-documented case of a young patient with embryonal rhabdomyosarcoma. The author, M. Léon Bérard, was a hospital fellow working in the department of M. Vincent at the Charité Hospital. The document was presented to La Société des Sciences médicales de Lyon (The Society of Medical Sciences of Lyon, France), in July,1894. The translation follows below.

Demographic and Treatment Variables Influencing Outcome for Localized Paratesticular Rhabdomyosarcoma: Results From a Pooled Analysis of North American and European Cooperative Groups

PURPOSE

Treatment recommendations for localized paratesticular rhabdomyosarcoma (PT RMS) differ in North America and Europe. We conducted a pooled analysis to identify demographic features and treatment choices that affect outcome.

PATIENTS AND METHODS

We retrospectively analyzed the effect of nine demographic variables and four treatment choices on event-free survival (EFS) and overall survival (OS) from 12 studies conducted by five cooperative groups.

RESULTS

Eight hundred forty-two patients with localized PT RMS who enrolled from 1988 to 2013 were included. Patients age ≥ 10 years were more likely than younger patients to have tumors that were > 5 cm, enlarged nodes (N1), or pathologically involved nodes ( P ≤ .05 each). With a median follow-up of 7.5 years, Kaplan-Meier estimates for 5-year EFS and OS were 87.7% and 94.8%, respectively. Of demographic variables, cooperative group, era of enrollment, age category, tumor size, Intergroup Rhabdomyosarcoma Study group, and T stage affected EFS ( P ≤ .05 each). Surgical assessment of regional nodes, which was performed in 23.5% of patients-usually in those age ≥ 10 years or with suspicious or N1 nodes-was the only treatment variable associated with EFS by univariable and multivariable analyses ( P ≤ .05 each) in patients age ≥ 1 year. A variable selection procedure on a proportional hazards regression model selected era of enrollment, age, tumor size, and surgical assessment of regional nodes as significant ( P ≤ .05 each) in the EFS model, and era of enrollment, age, tumor size, and histology ( P ≤ .05 each) in the OS model.

CONCLUSION

Localized PT RMS has a favorable prognosis. Age ≥ 10 years at diagnosis and tumor size larger than 5 cm are unfavorable prognostic features. Surgical assessment of regional nodes is important in patients age ≥ 10 years and in those with N1 nodes as it affects EFS.

[Palliative care for children in onco-hematology: Role of a specific home-care team]

BACKGROUND/OBJECTIVE

Our home-care unit (HCU) is specialized for pediatric cancer patients and has a strong palliative care activity. We believe that the introduction of home-care services can influence the place of palliative care and of death as well as the length of hospitalization. We aimed at describing characteristics and care course of patients treated in our HCU, and tried to identify some factors contributing to home care at the end of life.

DESIGN/METHODS

We conducted a retrospective, observational, monocentric study about patients in pediatric onco-hematology, treated at least one day in our home-care unit, who died between July 1st 2013 and December 31st 2015. Statistical analysis was descriptive and analytic.

RESULTS

A total of 74 patients known by our HCU died during study period. Eight were excluded. Forty-three out of 66 patients died at home. During the last 3 months of life, oncology patients have significantly less classical hospitalization, when compared to hematology patients. The implication of general physicians (GP) and nurses and information given to the family increase the possibility for home death. No significant association was found between ages at death, distance between home and hospital, other life conditions and place of death.

CONCLUSIONS

Our HCU has a strong palliative care activity and a high rate of children dying at home. Good collaborations between our pediatric onco-hematology team and our HCU as well as between our HCU and caregivers optimize palliative care.

Localized vaginal/uterine rhabdomyosarcoma-results of a pooled analysis from four international cooperative groups

BACKGROUND

Vaginal/uterine rhabdomyosarcoma (VU RMS) is one of the most favorable RMS sites. To determine the optimal therapy, the experience of four cooperative groups (Children's Oncology Group [COG], International Society of Pediatric Oncology (SIOP) Malignant Mesenchymal Tumor Group [MMT], Italian Cooperative Soft Tissue Sarcoma Group [ICG], and European pediatric Soft tissue sarcoma Study Group [EpSSG]) was analyzed.

PROCEDURE

From 1981 to 2009, 237 patients were identified. Median age (years) at diagnosis differed by tumor location; it was 1.9 for vagina (n = 160), 2.7 for uterus corpus (n = 26), and 13.5 for uterus cervix (n = 51). Twenty-eight percent of patients received radiation therapy (RT) as part of primary therapy (23% COG, 27% MMT, 46% ICG, and 42% EpSSG), with significant differences in the use of brachytherapy between the cooperative groups (23% COG, 76% MMT, 64% ICG, and 88% EpSSG).

RESULTS

Ten-year event-free (EFS) and overall survival (OS) were 74% (95% CI, 67-79%) and 92% (95% CI, 88-96%), respectively. In univariate analysis, OS was inferior for patients with uterine RMS and for those with regional lymph node involvement. Although EFS was slightly lower in patients without initial RT (71% without RT vs. 81% with RT; P = 0.08), there was no difference in OS (94% without RT vs. 89% with RT; P = 0.18). Local control using brachytherapy was excellent (93%). Fifty-one (51.5%) of the 99 survivors with known primary therapy and treatment for relapse were cured with chemotherapy with or without conservative surgery.

CONCLUSIONS

About half of all patients with VU RMS can be cured without systematic RT or radical surgery. When RT is indicated, modalities that limit sequelae should be considered, such as brachytherapy.

Relapse of Wilms' tumour and detection methods: a retrospective analysis of the 2001 Renal Tumour Study Group-International Society of Paediatric Oncology Wilms' tumour protocol database

BACKGROUND

Wilms' tumour is the most common renal cancer in childhood and about 15% of patients will relapse. There is scarce evidence about optimal surveillance schedules and methods for detection of tumour relapse after therapy.

METHODS

The Renal Tumour Study Group-International Society of Paediatric Oncology (RTSG-SIOP) Wilms' tumour 2001 trial and study is an international, multicentre, prospective registration, biological study with an embedded randomised clinical trial for children with renal tumours aged between 6 months and 18 years. The study covers 243 different centres in 27 countries grouped into five consortia. The current protocol of SIOP surveillance for Wilms' tumour recommends that abdominal ultrasound and chest x-ray should be done every 3 months for the first 2 years after treatment and be repeated every 4-6 months in the third and fourth year and annually in the fifth year. In this retrospective cohort study of the protocol database, we analysed data from participating institutions on timing, anatomical site, and mode of detection of all first relapses of Wilms' tumour. The primary outcomes were how relapse of Wilms' tumour was detected (ie, at or between scheduled surveillance and with or without clinical symptoms, scan modality, and physical examination) and to estimate the number of scans needed to capture one subclinical relapse. The RTSG-SIOP study is registered with Eudra-CT, number 2007-004591-39.

FINDINGS

Between June 26, 2001, and May 8, 2015, of 4271 eligible patients in the 2001 RTSG-SIOP Wilms' tumour database, 538 (13%) relapsed. Median follow-up from surgery was 62 months (IQR 32-93). The method used to detect relapse was registered for 410 (76%) of 538 relapses. Planned surveillance imaging captured 289 (70%) of these 410 relapses. The primary imaging modality used to detect relapse was reported for 251 patients, among which relapse was identified by abdominal ultrasound (80 [32%] patients), chest x-ray (78 [31%]), CT scan of the chest (64 [25%]) or abdomen (20 [8%]), and abdominal MRI (nine [4%]). 279 (68%) of 410 relapses were not detectable by physical examination and 261 (64%) patients did not have clinical symptoms at relapse. The estimated number of scans needed to detect one subclinical relapse during the first 2 years after nephrectomy was 112 (95% CI 106-119) and, for 2-5 years after nephrectomy, 500 (416-588).

INTERPRETATION

Planned surveillance imaging captured more than two-thirds of predominantly asymptomatic relapses of Wilms' tumours, with most detected by abdominal ultrasound, chest x-ray, or chest CT scan. Beyond 2 years post-nephrectomy, a substantial number of surveillance scans are needed to capture one relapse, which places a burden on families and health-care systems.

FUNDING

Great Ormond Street Hospital Children's Charity, the European Expert Paediatric Oncology Reference Network for Diagnostics and Treatment, The Danish Childhood Cancer Foundation, Cancer Research UK, the UK National Cancer Research Network and Children's Cancer and Leukaemia Group, Société Française des Cancers de l'Enfant and Association Leon Berard Enfant Cancéreux and Enfant et Santé, Gesellschaft für Pädiatrische Onkologie und Hämatologie and Deutsche Krebshilfe, Grupo Cooperativo Brasileiro para o Tratamento do Tumor de Wilms and Sociedade Brasileira de Oncologia Pediátrica, the Spanish Society of Pediatric Haematology and Oncology and the Spanish Association Against Cancer, and SIOP-Netherlands.

Addition of dose-intensified doxorubicin to standard chemotherapy for rhabdomyosarcoma (EpSSG RMS 2005): a multicentre, open-label, randomised controlled, phase 3 trial

BACKGROUND

Rhabdomyosarcoma is an aggressive tumour that can develop in almost any part of the body. Doxorubicin is an effective drug against rhabdomyosarcoma, but its role in combination with an established multidrug regimen remains controversial. Therefore, we aimed to evaluate the possible benefit of early dose intensification with doxorubicin in patients with non-metastatic rhabdomyosarcoma.

METHODS

We did a multicentre, open-label, randomised controlled, phase 3 trial involving 108 hospitals from 14 countries. We included patients older than 6 months but younger than 21 years with a pathologically proven diagnosis of rhabdomyosarcoma. We assigned each patient to a specific subgroup according to the EpSSG stratification system. Those with embryonal rhabdomyosarcoma incompletely resected and localised at unfavourable sites with or without nodal involvement, or those with alveolar rhabdomyosarcoma without nodal involvement were considered at high risk of relapse. These high-risk patients were randomly assigned (1:1) to receive either nine cycles of IVA (ifosfamide 3 g/m2 given as a 3-h intravenous infusion on days 1 and 2, vincristine 1·5 mg/m2 weekly during the first 7 weeks then only on day 1 of each cycle [given as a single intravenous injection], and dactinomycin 1·5 mg/m2 on day 1 given as a single intravenous injection) or four cycles of IVA with doxorubicin 30 mg/m2 given as a 4-h intravenous infusion on days 1 and 2 followed by five cycles of IVA. The interval between cycles was 3 weeks. Randomisation was done using a web-based system and was stratified (block sizes of four) by enrolling country and risk subgroup. Neither investigators nor patients were masked to treatment allocation. The primary endpoint was 3-year event-free survival assessed by the investigator at each centre in the intention-to-treat population. Patients who received at least one dose of study treatment were considered in the safety analysis. In agreement with the independent data monitoring committee, the study was closed to patient entry on Dec 16, 2013, after futility analysis. This trial is registered with EudraCT, number 2005-000217-35, and is currently in follow-up.

FINDINGS

Between Oct 1, 2005, and Dec 16, 2013, 484 patients were randomly assigned to receive each chemotherapy regimen (242 in the IVA group and 242 in the IVA plus doxorubicin group). Median follow-up was 63·9 months (IQR 44·6-78·9). The 3-year event-free survival was 67·5% (95% CI 61·2-73·1) in the IVA plus doxorubicin group and 63·3% (56·8-69·0) in the IVA group (hazard ratio 0·87, 95% CI 0·65-1·16; p=0·33). Grade 3-4 leucopenia (232 [93%] of 249 patients in the IVA plus doxorubicin group vs 194 [85%] of 227 in the IVA group; p=0·0061), anaemia (195 [78%] vs 111 [49%]; p<0·0001), thrombocytopenia (168 [67%] vs 59 [26%]; p<0.0001), and gastrointestinal adverse events (78 [31%] vs 19 [8%]; p<0·0001) were significantly more common in the IVA plus doxorubicin group than in the IVA group. Grade 3-5 infections (198 [79%] vs 128 [56%]; p<0·0001) were also significantly more common in the IVA plus doxorubicin group than in the IVA group, in which one patient had grade 5 infection. Two treatment-related deaths were reported (one patient developed septic shock and one affected by Goldenhar syndrome developed intractable seizures) in the IVA plus doxorubicin group, both occurring after the first cycle of treatment, and none were reported in the IVA group.

INTERPRETATIONS

The addition of dose-intensified doxorubicin to standard IVA chemotherapy did not show a significant improvement in the outcome of patients with high-risk non-metastatic rhabdomyosarcoma. Therefore, the IVA chemotherapy regimen should remain the standard of care for patients with localised rhabdomyosarcoma in Europe.

FUNDING

Fondazione Città della Speranza, Italy, and the Association Léon Berard Enfant Cancéreux, France.

Evaluation of boost irradiation in patients with intermediate-risk stage III Wilms tumour with positive lymph nodes only: Results from the SIOP-WT-2001 Registry

OBJECTIVE

To evaluate the value of radiotherapy boost omission in patients with intermediate-risk, stage III Wilms tumours (WT) with positive lymph nodes (LN).

METHODS AND MATERIALS

All patients with intermediate-risk, stage III (LN positive) WT consecutively registered in the SIOP-WT-2001 study were included in this analysis. Endpoints were 5-year event-free survival (EFS), loco-regional control (LRC) and overall survival (OS).

RESULTS

Between June 2001 and May 2015, 2,569 patients with stage I to III WT after preoperative chemotherapy were registered in the SIOP-WT-2001 study. Five hundred and twenty-three (20%) had stage III disease, of which 113 patients had stage III due to positive LN only. Of those, 101 (89%) received radiotherapy, 36 of which (36%) received, apart from flank irradiation, a boost dose to the LN positive area. Four patients (4%) did not receive any adjuvant radiotherapy. In eight patients information on radiotherapy was not available. With a median follow-up of 71 months, no difference in 5-year EFS (84% vs. 83%, P = 0.77) and LRC (96% vs. 97%, P = 0.91) was observed between patients receiving a radiotherapy boost and those without boost, respectively. Five-year OS, including salvage therapy, was excellent (boost vs. no boost: 97% vs. 95%, P = 0.58).

CONCLUSIONS

Outcome data demonstrate that omission of the radiotherapy boost to the loco-regional positive lymph nodes in patients with intermediate-risk, stage III WT who receive preoperative chemotherapy and postoperative flank irradiation (14.4 Gy) can be considered a safe approach for future SIOP protocols.

Abstract 4934: Immunostimulatory and oncolytic properties of rotavirus can overcome resistance to immune checkpoint blockade therapy

Immune checkpoint targeted therapies against PD-1, PD-L1 and CTLA-4 are currently revolutionizing cancer care. However, only a minority of patients generate objective tumor responses with these treatments. Therefore, new therapeutic interventions are needed to increase the immunogenicity of tumors in order to overcome the resistance to immune checkpoint blockade therapy. Pattern recognition receptors (PRR) such as toll-like receptor agonists have been shown to overcome resistance to immune checkpoint targeted therapy in pre-clinical models. Besides their intrinsic ability to stimulate PRR, the oncolytic properties of common viruses can be exploited also for the priming of anti-tumor immune responses. Several oncolytic viruses are currently in clinical development for cancer immunotherapy. However the routine implementation of these therapies is limited by the ongoing regulations on GMOs. With the aim to analyze if anti-infectious vaccines can be used as a source or PRR agonists and/or oncolytic viruses, we infected different tumors cell lines with commercially available anti-infectious vaccines. We first confirmed that commercially available vaccines do have PRR agonist properties. More interestingly, we discovered that rotavirus vaccines also have oncolytic properties. These attenuated viruses can directly kill cancer cells with features of immunogenic cell death such as upregulation of calreticulin on dying cancer cells but doesn't have cytotoxicity on healthy primary fibroblasts. Moreover, they have pro-inflammatory properties and can activate the NF-KB pathway in a toll-like receptor and IRF3 independent manner. These in vitro biological properties translate into in vivo anti-tumor activity. Intra-tumoral (IT) rotavirus therapy has anti-tumor effects which are mainly immune mediated as demonstrated by their weaken activity in NSG mice. Interestingly, in immunocompetent syngeneic murine tumor models of neuroblastoma and lymphoma, IT rotavirus therapy can overcome resistance to immune checkpoint targeted therapy and in particular synergies with anti-CTLA4. This therapeutic effect relied on specific modifications of tumor immune infiltrates and immune activation pathways. IT rotavirus vaccines was associated to an increase of myeloid infiltrating cells expressing up-regulated level of CD86 in the tumor microenvironment, and upregulation of activation markers such as OX40/CD137 on T cells. Rotavirus vaccines are clinical grade products, including for children. Therefore, in situ immunization strategies with IT attenuated rotavirus can be implemented quickly in the clinic including in pediatric cancers. IT priming of the anti-tumor immunity with oncolytic and immunostimulatory rotavirus vaccines could be a feasible strategy to overcome resistance to anti-PD-1/anti-CTLA-4 therapy in patients with cancer.* co-last authors.

Citation Format: Tala Shekarian, Stéphane Depil, Anne-Catherine Jallas, Christophe Bergeron, Christophe Caux, Aurélien Marabelle, Sandrine Valsesia-Wittmann. Immunostimulatory and oncolytic properties of rotavirus can overcome resistance to immune checkpoint blockade therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4934.

Phase I results of a phase I/II study of weekly nab-paclitaxel in paediatric patients with recurrent/refractory solid tumours: A collaboration with innovative therapies for children with cancer

BACKGROUND

nab-Paclitaxel has demonstrated efficacy in adults with solid tumours and preclinical activity in paediatric solid tumour models. Results from phase I of a phase I/II study in paediatric patients with recurrent/refractory solid tumours treated with nab-paclitaxel are reported.

PATIENTS AND METHODS

Patients with recurrent/refractory extracranial solid tumours received nab-paclitaxel on days 1, 8 and 15 every 4 weeks at 120, 150, 180, 210, 240, or 270 mg/m² (rolling-6 dose-escalation) to establish the maximum tolerated dose (MTD) and recommended phase II dose (RP2D).

RESULTS

Sixty-four patients were treated. Dose-limiting toxicities were grade 3 dizziness at 120 mg/m² and grade 4 neutropenia >7 days at 270 mg/m². The most frequent grade 3/4 adverse events were haematologic, including neutropenia (36%), leukopenia (36%) and lymphopenia (25%). Although the MTD was not reached, 270 mg/m² was declared non-tolerable due to grade 3/4 toxicities during cycles 1-2 (neutropenia, n = 5/7; skin toxicity, n = 2/7; peripheral neuropathy, n = 1/7). Of 58 efficacy-evaluable patients, complete response occurred in one patient (2%; Ewing sarcoma) and partial responses in four patients (7%; rhabdomyosarcoma, Ewing sarcoma, renal tumour with pulmonary metastases [high-grade, malignant] and sarcoma not otherwise specified); all responses occurred at ≥210 mg/m². Thirteen patients (22%) had stable disease (5 lasting ≥16 weeks) per RECIST.

CONCLUSIONS

nab-Paclitaxel 240 mg/m² qw3/4 (nearly double the adult recommended monotherapy dose for this schedule in metastatic breast cancer) was selected as the RP2D based on the tolerability profile, pharmacokinetics and antitumour activity. Phase II is currently enrolling patients with recurrent/refractory neuroblastoma, rhabdomyosarcoma and Ewing sarcoma. CLINICALTRIALS.GOV: NCT01962103.

EUDRACT

2013-000144-26.

Maintenance low-dose chemotherapy in patients with high-risk (HR) rhabdomyosarcoma (RMS): A report from the European Paediatric Soft Tissue Sarcoma Study Group (EpSSG)

LBA2

Background: Most patients with localized RMS achieve complete remission during standard (std) treatment but approximately 20-30% of them relapse and chance of salvage is poor. We tested whether adding maintenance metronomic chemotherapy after std chemotherapy would improve survival for patients with non metastatic RMS defined as HR according to EpSSG stratification. Methods: Patients (pts) age >6 months <21 years, with N0 alveolar (A)RMS or incompletely resected (Group II or III) embryonal (E)RMS arising in an unfavorable primary site and/or N1 in complete remission after std treatment including 9 cycles of ifosfamide, vincristine and actinomycin D +/- doxorubicin, surgery and/or radiotherapy were eligible for randomization to stop treatment (Std-arm) or receive maintenance chemotherapy (M-arm) with 6 28-day cycles of iv vinorelbine 25 mg/m2 on day 1,8,15 of each cycle and continuous daily oral cyclophosphamide 25 mg/m2 . The study was initially designed with 80% power (5% 2-sided alpha level) to detect an increase in 3 yr Event Free Survival (EFS) from 55% to 67%, a Hazard Ratio of 0.67, but was successively amended to allow a detection of a relative reduction in the relapse rate of 50% in the M-arm, with 80% power, testing at the 5% significance level (2-sided). Results: 670 pts were entered between 4/2006-12/2016, with 371 confirmed eligible and 186 assigned to the std-arm and 185 to M-arm. Clinical features were well balanced in the two arms and included ERMS 67%, ARMS 33%, age 10+ years 21%; IRS Group III 86%; N1 16%. Most common primary tumor sites were parameningeal (32%) and “other” sites (23%). With median follow up of 5 years in surviving pts, 3 yr EFS and overall survival (OS) in M-arm vs Std-arm were respectively: EFS 78.4% (95% IC -71.5-83.8) vs 72.3% (95% IC -65.0-78.3) (p 0.061) and OS 87.3% (95% IC 81.2-91.6) vs 77.4 (95% IC 70.1-83.1) (p = 0.011). Toxicity in the M-arm was manageable: grade 3/4 febrile neutropenia in 25% of pts, grade 4 neurotoxicity in 1.1%. Conclusions: The addition of maintenance after std treatment significantly improves OS in HR RMS patients and support its inclusion in future EpSSG trials. Clinical trial information: 2005-000217-35.

Fusion status in patients with lymph node-positive (N1) alveolar rhabdomyosarcoma is a powerful predictor of prognosis: Experience of the European Paediatric Soft Tissue Sarcoma Study Group (EpSSG)

BACKGROUND

Alveolar rhabdomyosarcoma (aRMS) with lymph node involvement (N1 classification) accounts for up to 10% of all cases of RMS. The prognosis is poor, and is comparable to that of distant metastatic disease. In the European Paediatric Soft Tissue Sarcoma Study Group (EpSSG) RMS2005 protocol, patients with a histologic diagnosis of aRMS/N1 received intensified chemotherapy with systematic locoregional treatment.

METHODS

Patients with aRMS/N1 were enrolled prospectively after primary surgery/biopsy and fusion status was assessed in tumor samples. All patients received 9 cycles of induction chemotherapy and 6 months of maintenance therapy. Local treatment included radiotherapy to the primary site and lymph nodes with or without secondary surgical resection.

RESULTS

A total of 103 patients were enrolled. The clinical characteristics of the patients were predominantly unfavorable: 90% had macroscopic residual disease after initial surgery/biopsy, 63% had locally invasive tumors, 77% had a tumor measuring >5 cm, and 81% had disease at unfavorable sites. Fusion genes involving forkhead box protein O1 (FOXO1) were detected in 56 of 84 patients. Events occurred in 52 patients: 43 developed disease recurrence, 7 had disease that was refractory to treatment, and 2 patients developed second neoplasms. On univariate analysis, unfavorable disease site, tumor invasiveness, Intergroup Rhabdomyosarcoma Study group III, and fusion-positive status correlated with worse prognosis. The 5-year event-free survival rate of patients with fusion-positive tumors was 43% compared with 74% in patients with fusion-negative tumors (P = .01). On multivariate analysis, fusion positivity and tumor invasiveness proved to be unfavorable prognostic markers.

CONCLUSIONS

Fusion status and tumor invasiveness appear to have a strong impact on prognosis in patients with aRMS/N1. Fusion status will be used to stratify these patients in the next EpSSG RMS study, and treatment will be intensified in patients with fusion-positive tumors. Cancer 2018. © 2018 American Cancer Society.

Continuous intravenous vancomycin in children with normal renal function hospitalized in hematology-oncology: prospective validation of a dosing regimen optimizing steady-state concentration

Continuous intravenous (IV) infusion has been shown to be the best option to administer vancomycin because of its time-dependent bactericidal activity. Available IV vancomycin dosing guidelines in pediatrics with normal renal function leads to less than 50% of patients achieving a vancomycin serum concentration (Css) in the target range (15-20 mg/L). The primary objective of this study was to prospectively validate an age-based dosing regimen in pediatric oncology-hematology. The secondary objective was to investigate the influence on Css attainment of different variables. A continuous IV dosing nomogram was built by retrospective study (2000-2010) on Bayesian dosing adjustments performed in 161 patients. This study assessed the prospective validation of this age-based nomogram and the influence on Css attainment of variables as the gender, underlying disease (oncology or hematology), and hematopoietic stem cell transplantation (HSCT) before receiving vancomycin therapy. A total of 94 patients aged from 4.3 months to 17.9 years old with normal renal function were eligible for the prospective validation. Fifty-five of those patients (58.5%) achieved the target range of vancomycin Css. There was no significant difference between age groups (P = 0.816) and no influence of gender (P = 0.500). There was a nonsignificant trend to a better target attainment in oncology patients (69.2% vs. hematology 54.4%, P = 0.142) and patients who did not undergo HSCT (63.3% vs. 33.3%, P = 0.031). This study proposed an age-based nomogram prospectively validated which near 60% of patients of each age class achieving the target range of Css.

Position paper: Rationale for the treatment of children with CCSK in the UMBRELLA SIOP-RTSG 2016 protocol

The International Society of Paediatric Oncology-Renal Tumour Study Group (SIOP-RTSG) has developed a new protocol for the diagnosis, treatment, and follow-up monitoring of childhood renal tumours - the UMBRELLA SIOP-RTSG 2016 protocol (the UMBRELLA protocol). This protocol has been designed to continue international collaboration in the treatment of childhood renal tumours and will be implemented in over 50 different countries. Clear cell sarcoma of the kidney, which is a rare paediatric renal tumour that most commonly occurs in children between 2 and 4 years of age, is specifically addressed in the UMBRELLA protocol.

Irinotecan for relapsed Wilms tumor in pediatric patients: SIOP experience and review of the literature-A report from the SIOP Renal Tumor Study Group

While irinotecan has been studied in various pediatric solid tumors, its potential role in Wilms tumor (WT) is less clear. We evaluated response and outcome of irinotecan-containing regimens in relapsed WT and compared our results to the available literature. Among 14 evaluable patients, one complete response (CR) and two partial responses (PRs) were observed in patients with initial intermediate-risk (CR and PR) and blastemal-type histologies (PR). Two patients were alive at last follow-up showing no evidence of disease. Our results and the reviewed literature suggest some effectiveness of irinotecan in the setting of relapsed WT.

Position paper: Rationale for the treatment of Wilms tumour in the UMBRELLA SIOP-RTSG 2016 protocol

The Renal Tumour Study Group of the International Society of Paediatric Oncology (SIOP-RTSG) has developed a new protocol for the diagnosis and treatment of childhood renal tumours, the UMBRELLA SIOP-RTSG 2016 (the UMBRELLA protocol), to continue international collaboration in the treatment of childhood renal tumours. This protocol will support integrated biomarker and imaging research, focussing on assessing the independent prognostic value of genomic changes within the tumour and the volume of the blastemal component that survives preoperative chemotherapy. Treatment guidelines for Wilms tumours in the UMBRELLA protocol include recommendations for localized, metastatic, and bilateral disease, for all age groups, and for relapsed disease. These recommendations have been established by a multidisciplinary panel of leading experts on renal tumours within the SIOP-RTSG. The UMBRELLA protocol should promote international collaboration and research and serve as the SIOP-RTSG best available treatment standard.

Phase II study of ipilimumab in adolescents with unresectable stage III or IV malignant melanoma

BACKGROUND

Ipilimumab is approved for the treatment of advanced melanoma in adults; however, little information on the efficacy and safety of ipilimumab in younger patients is available.

METHODS

Patients aged 12 to <18 years with previously treated or untreated, unresectable stage III or IV malignant melanoma received ipilimumab 3 or 10 mg/kg every 3 weeks. Primary end-points were 1-year overall survival and safety.

RESULTS

Over a period of 3.5 years, 12 patients received ipilimumab at either 3 mg/kg (n = 4) or 10 mg/kg (n = 8). The median number of ipilimumab doses was four for 3 mg/kg and three for 10 mg/kg. At 1 year, three of four patients on 3 mg/kg and five of eight patients on 10 mg/kg were alive. Two patients on 10 mg/kg had partial response, and one on 3 mg/kg had stable disease. One patient had durable partial response at 3 years without further treatment, at time of this report. There was one grade 3/4 immune-mediated adverse reaction with 3 mg/kg and five with 10 mg/kg. There were no treatment-related deaths. The study was stopped due to slow accrual.

CONCLUSIONS

At >1 year follow-up, ipilimumab demonstrated activity in melanoma patients aged 12 to <18 years, with a similar safety profile as that seen in adults. Our trial highlights the difficulties of enrolling younger patients with rare diseases in clinical trials for treatments that are approved in adults, suggesting adolescents with cancer types occurring predominantly in adults should be considered for inclusion in adult trials of promising new drugs.

CLINICAL TRIAL REGISTRATION

NCT01696045.

Microenvironment-Driven Shift of Cohesion/Detachment Balance within Tumors Induces a Switch toward Metastasis in Neuroblastoma

Neuroblastoma (NB) is a childhood cancer arising from sympatho-adrenal neural crest cells. Disseminated forms have high frequency of multiple tumoral foci whose etiology remains unknown; NB embryonic origin limits investigations in patients and current models. We developed an avian embryonic model driving human NB tumorigenesis in tissues homologous to patients. We found that aggressive NBs display a metastatic mode, secondary dissemination via peripheral nerves and aorta. Through tumor transcriptional profiling, we found that NB dissemination is induced by the shutdown of a pro-cohesion autocrine signal, SEMA3C, which constrains the tumoral mass. Lowering SEMA3C levels shifts the balance toward detachment, triggering NB cells to collectively evade the tumor. Together with patient cohort analysis, this identifies a microenvironment-driven pro-metastatic switch for NB.