Klinefelter syndrome in males with germ cell tumors: A report from the Children's Oncology Group

BACKGROUND

Males with Klinefelter syndrome (KS) (47,XXY) may be more likely to develop germ cell tumors (GCTs), particularly mediastinal GCTs. To date, there are no reports characterizing the prevalence of KS among male GCT cases.

METHODS

The authors used array genotyping data from a Children's Oncology Group epidemiology study to estimate the prevalence of KS in males with GCTs (433 males aged birth-19 years). Using Fisher's exact tests, the authors examined differences in age at diagnosis, race/ethnicity, tumor location and histology, and several birth characteristics between cases of KS-GCT and GCT cases without chromosomal abnormalities. Using publicly available data, the authors estimated the 1-year risk, risk ratio, and corresponding 95% confidence interval of GCTs among KS cases.

RESULTS

Based on analysis of array genotyping data, 3% of male GCT cases (13 cases) had KS. The additional X chromosome was of maternal origin in 7 of the 13 cases. Of these 13 KS cases, 5 of 9 KS-GCT cases with parental questionnaire data (56%) reported a diagnosis of KS. No significant differences were observed with regard to patient or birth characteristics between KS-GCT and non-KS-GCT cases. KS-GCT cases were significantly more likely to be diagnosed with mediastinal tumors than non-KS-GCT cases (P<.01). The authors estimated the risk of developing a GCT among males with KS to be 0.00025, or 1 per 4000 males (risk ratio, 18.8; 95% confidence interval, 11.7-30.0).

CONCLUSIONS

Compared with males without chromosomal abnormalities, males with KS are more likely to be diagnosed with a mediastinal GCT. The presence of KS should be considered in males with a diagnosis of mediastinal GCT. In the current study, the authors report that approximately one-third of males with mediastinal germ cell tumors have Klinefelter syndrome, and therefore screening of these individuals for the syndrome may be warranted. Males with Klinefelter syndrome are 19 times as likely as males without Klinefelter syndrome to develop germ cell tumors.

Differences in DNA methylation profiles by histologic subtype of paediatric germ cell tumours: a report from the Children's Oncology Group

Background

Abnormal DNA methylation may be important in germ cell tumour (GCT) aetiology, as germ cells undergo complete epigenetic reprogramming during development. GCTs show differences in global and promoter methylation patterns by histologic subtype. We conducted an epigenome-wide study to identify methylation differences by GCT histology.

Methods

Using the Illumina HumanMethylation450K array we measured methylation in 154 paediatric GCTs (21 germinomas/seminomas/dysgerminoma, 70 yolk sac tumours [YST], 9 teratomas, and 54 mixed histology tumours). We identified differentially methylated regions (DMRs) between GCT histologies by comparing methylation beta values.

Results

We identified 8,481 DMRs (FWER < 0.05). Unsupervised hierarchical clustering of individual probes within DMRs resulted in four high level clusters closely corresponding to tumour histology. Clusters corresponding to age, location, sex and FFPE status were not observed within these DMRs. Germinomas displayed lower levels of methylation across the DMRs relative to the other histologic subtypes. Pathway analysis on the top 10% of genes with differential methylation in germinomas/seminomas/dysgerminoma compared to YST suggested angiogenesis and immune cell-related pathways displayed decreased methylation in germinomas/seminomas/dysgerminoma relative to YST.

Conclusions

Paediatric GCT histologies have differential methylation patterns. The genes that are differentially methylated may provide insights into GCT aetiology including the timing of GCT initiation.

Abstract A25: Prevalence of Klinefelter syndrome among males aged 0-19 years diagnosed with germ cell tumors: A report from the Children’s Oncology Group

Previous studies have suggested that males with Klinefelter syndrome (KS; 47, XXY) may be more likely to develop germ cell tumors (GCTs), particularly mediastinal GCTs. Due to the rarity of pediatric GCTs, there are no reports characterizing the prevalence of KS among males diagnosed with GCTs.

We used data from a Children’s Oncology Group epidemiology study (2008-2015) to evaluate the prevalence of KS in males (n=433) diagnosed with GCTs (aged 0-19 years). These 433 cases provided saliva samples and had one parent who was willing to participate in the study and complete a questionnaire including questions about health history, demographics, and environmental exposures. Tumor characteristics (location and histology) were abstracted from pathology reports provided by the treating institution. GCT cases were classified as having KS if they had evidence of an extra copy of the X chromosome based on evaluation of array data from Illumina HumanCoreExome-12 genotyping chips. Genvisis was used to identify samples with sex aneuploidy and to determine the parent-of-origin for the nondisjunction. Using chi-square tests, we examined differences in age at diagnosis, race/ethnicity, tumor location and histology, and a number of birth characteristics between KS-GCT cases and GCT cases without chromosomal abnormalities (n=415). Using publically available data, we estimated the 1-year risk and corresponding Risk Ratio (RR) and 95% Confidence Interval (95% CI) of a male with KS developing a GCT.

Based on analysis of array genotyping data, 3% (n=13) of male GCT cases had KS. Among these 13 cases, the extra X chromosome was of maternal origin in 7 cases and of paternal origin in 6 cases. Of the 13 KS cases with genotyping data, 5/9 (56%) KS-GCT cases with parental questionnaire data reported receiving a diagnosis of KS. The average age at GCT diagnosis for cases with genotyping-detected KS (n=13) was 13.8 years (standard deviation [SD], 4.4 years) compared with 12.5 years (SD, 6.2 years) for GCT cases without chromosomal abnormalities (n=415; p=0.45). We did not observe significant differences in patient or birth characteristics including race, birth weight and length, maternal age, paternal age, and the use of fertility drugs between the two groups. We confirmed that KS-GCT cases were significantly more likely to be diagnosed with extragonadal tumors (GCT [n=69/411; 17%]; KS-GCT [n=11/13; 85%]; p&lt;0.01), particularly mediastinal tumors (GCT [n=20/406; 5%]; KS-GCT [9/13; 69%]; p&lt;0.01), than GCT cases without chromosomal abnormalities. Mixed/other histology was the most common histologic subtype for KS-GCT (46%) and GCTs among patients without chromosomal abnormalities (41%; p=0.60). Based on data from the CDC WONDER database and the US Census Bureau, in 2013, the risk of developing a GCT among males aged 0-19 years without KS was estimated to be 0.000014 or approximately 1 in 70,000. Using our estimate that 3% of GCTs in males aged 0-19 years are diagnosed among patients who also have KS, we estimated the risk of a GCT among males with KS to be 0.00025, or approximately 1 in 4,000 (RR: 18.8; 95% CI: 11.7, 30.0).

In our large case series of males diagnosed with GCTs, we observed that 3% of GCT cases (n=13/433) were also carriers of an extra X chromosome based on array genotyping data and were thus classified as having KS. Males aged 0-19 years with KS experience a large increase in risk of developing a GCT compared with males from the general population. Collectively, these findings suggest that young males with KS should be monitored for the development of a GCT. Similarly, the possibility of KS should be considered in males diagnosed with a mediastinal GCT during childhood or adolescence and these patients should be tested for the presence of KS.

Citation Format: Lindsay A. Williams, Nathan Pankratz, John Lane, Michelle Roesler, Michaela Richardson, A. Lindsay Frazier, James Amatruda, Jenny N. Poynter. Prevalence of Klinefelter syndrome among males aged 0-19 years diagnosed with germ cell tumors: A report from the Children’s Oncology Group [abstract]. In: Proceedings of the AACR Special Conference: Pediatric Cancer Research: From Basic Science to the Clinic; 2017 Dec 3-6; Atlanta, Georgia. Philadelphia (PA): AACR; Cancer Res 2018;78(19 Suppl):Abstract nr A25.

Treatment of refractory germ cell tumors in children with paclitaxel, ifosfamide, and carboplatin: A report from the Children's Oncology Group AGCT0521 study

BACKGROUND

Paclitaxel, ifosfamide, cisplatin (TIP) is commonly used as salvage for malignant germ cell tumors (MGCT) in adults; however, additional administration of cisplatin at a young age could cause significant short- and long-term toxicities in a group of patients with high expected salvage. Because carboplatin has been shown to be effective in pediatric MGCT with less toxicity, the TIP regimen was modified by substituting carboplatin for cisplatin.

METHODS

The Children's Oncology Group conducted a phase II trial between November 2007 and June 2011 evaluating "TIC" (paclitaxel 135 mg/m² /day Day 1, ifosfamide 1,800 mg/m² /dose Days 1-5 and carboplatin with AUC 6.5 Day 1) in children < 21 years with relapsed MGCT. The endpoint of the trial was response after two cycles, incorporating RECIST response and marker decline.

RESULTS

Twenty patients (12 male, median age 13.5 years) were enrolled. Seventeen patients had tumor markers ≥10 times above normal. After two cycles, by RECIST criteria, 8 patients achieved a partial response (response rate 40%), 10 had stable disease, and 2 had progressive disease. A ≥ 1 log reduction was achieved in 10/17 patients (58.8%) with elevated markers. By study defined criteria, combining response by RECIST and marker decline, the response rate was 44%.

CONCLUSION

TIC is active in relapsed pediatric MGCT and should be considered for salvage therapy in children. In adolescents and older adults with relapse MGCT, TIP or high-dose chemotherapy with stem cell remain the standard therapy.

Abstract 2064: Differences in methylation patterns by pediatric germ cell tumor histologic subtype

Anomalous DNA methylation contributes to carcinogenesis by regulating gene expression and may be important in germ cell tumor (GCT) development as germ cells undergo tremendous epigenetic reprogramming during embryogenesis. Histologic subtypes of GCTs show differences in global methylation patterns with less differentiated tumors (e.g. embryonal carcinoma) experiencing lower levels of global methylation relative to more differentiated tumors (e.g. teratoma). Differences in promoter methylation have also been reported in GCTs. In particular, developmental signaling pathways and the BMP/TGF beta pathway have been consistently found to be differentially methylated. In this analysis, we conducted an epigenome wide association study to identify gene-specific methylation differences by GCT histology. Using the Illumina HumanMethylation450K array we determined methylation profiles for 154 pediatric GCTs (21 germinomas, 54 mixed, 9 teratomas, 70 yolk sac tumors [YST]) from fresh frozen and formalin fixed paraffin embedded tumor tissue samples. Fisher's exact tests were used to assess differences in the distributions of age group, sex, and tumor location by histologic subtype (alpha=0.05 for a two-sided test of significance [SAS v9.4]). Bioconductor package minfi was used to identify differential methylation between GCT histologic subtypes by comparing the methylation beta values. To identify differential methylation of genes predictive of tumor histology, a generalized linear model (glm) with LASSO was fit (R v3.4.1) to the quantile normalized beta values for all probes from all samples. There were significant differences in age, sex, and tumor location by histologic subtype (all p&lt;0.01). We observed unique clusters for both germinoma and YST, but a single cluster for mixed tumors and teratoma. The methylation clusters did not differ by age, sex or FFPE status after accounting for histologic subtype. When stratifying by age group (0-10 vs. 11-19 years), we observed 2,043 differentially methylated regions (DMRs) (FWER &lt;0.05); however, these differences did not persist once we adjusted for tumor histology. Differential methylation tests across histologic subtypes resulted in 8,049 DMRs (FWER &lt; 0.05). Germinoma clustered most consistently and displayed a unique methylation pattern relative to other tumor types, which were more similar to one another. Fitting a glm with LASSO to the methylation data identified 21 probes that were predictive of histologic subtype with misclassification error &lt; 20%: ANKRD24, ASL, ATG13, CCDC53, CKB, FAM224B, FZD10, KCNMB3, LINC00939, LOC101927248, MIR378C, MMP14, MUC1, OGFOD3, PLP2, PLPP3, PRR5, SERPINA6¸ SGSM2, VARS, and YWHAZ. In our analyses, we identified a large number of genes with differential methylation by tumor histology. These data may be informative in understanding GCT etiology and the timing of GCT initiation.

Citation Format: Lindsay A. Williams, Lauren Mills, Anthony J. Hooten, Erica Langer, Michelle Roesler, A Lindsay Frazier, James Amatruda, Jenny N. Poynter, Jenny N. Poynter. Differences in methylation patterns by pediatric germ cell tumor histologic subtype [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 2064.

Prevention of cisplatin-induced hearing loss in children: Informing the design of future clinical trials

Cisplatin is an essential chemotherapeutic agent in the treatment of many pediatric cancers. Unfortunately, cisplatin-induced hearing loss (CIHL) is a common, clinically significant side effect with life-long ramifications, particularly for young children. ACCL05C1 and ACCL0431 are two recently completed Children's Oncology Group studies focused on the measurement and prevention of CIHL. The purpose of this paper was to gain insights from ACCL05C1 and ACCL0431, the first published cooperative group studies dedicated solely to CIHL, to inform the design of future pediatric otoprotection trials. Use of otoprotective agents is an attractive strategy for preventing CIHL, but their successful development must overcome a unique constellation of methodological challenges related to translating preclinical research into clinical trials that are feasible, evaluate practical interventions, and limit risk. Issues particularly important for children include use of appropriate methods for hearing assessment and CIHL severity grading, and use of trial designs that are well-informed by preclinical models and suitable for relatively small sample sizes. Increasing interest has made available new funding opportunities for expanding this urgently needed research.

Comparison of carboplatin versus cisplatin in the treatment of paediatric extracranial malignant germ cell tumours: A report of the Malignant Germ Cell International Consortium

PURPOSE

To compare the outcomes of paediatric and adolescent extracranial malignant germ cell tumour (GCT) patients treated with either carboplatin or cisplatin on clinical trials conducted by the Children's Oncology Group (COG) and the Children's Cancer and Leukaemia Group (CCLG).

METHODS

The Malignant Germ Cell International Consortium (MaGIC) has created a database of the GCT clinical trials conducted since 1983 by COG (United States, Canada and Australia), which used cisplatin-based regimens, and by CCLG (United Kingdom), which used carboplatin-based regimens. Using the parametric cure model, this study compared the overall 4-year event-free survival (EFS), stratified by age, stage, site and the a-priori defined MaGIC 'risk' groups: standard risk ((SR) 1 (EFS >80%; age <11 years), SR2 (EFS >80%, age ≥ 11y) and poor risk (PR) (EFS ≤ 70%, age ≥ 11y).

RESULTS

Cisplatin-based therapy was used in 620 patients; carboplatin was used in 163 patients. In the overall multivariate cure model, the two regimens did not differ significantly (cisplatin: 4-year EFS 86%; 95% confidence interval (CI) 83-89% versus carboplatin 4-year EFS 86%; 95% CI 79-90%; p = 0.87). No significant differences were noted in stratified analyses by site, stage, age and MaGIC risk groups: SR1 (p = 0.20), SR2 (p = 0.55) or PR (p = 0.72) patients.

CONCLUSIONS

In these trials conducted contemporaneously, there is no significant difference in outcome observed overall, or any subset of patients, who were treated with regimens containing cisplatin versus carboplatin These results suggested sufficient equipoise to justify a randomised trial to evaluate the effectiveness of carboplatin versus cisplatin in the treatment of children, adolescents and young adults with standard risk GCT, which is currently underway.

Is carboplatin-based chemotherapy as effective as cisplatin-based chemotherapy in the treatment of advanced-stage dysgerminoma in children, adolescents and young adults?

OBJECTIVE

Dysgerminoma is the most common malignant ovarian germ cell tumor (GCT) with peak incidence during adolescence and young adulthood. Current standard of care for patients with disease that has spread outside of the ovary (advanced-stage) utilizes platin-based chemotherapy regimens. The study objective was to compare clinical outcomes between platin-based (carboplatin versus cisplatin) strategies across all age groups (children < 11 years (y), adolescents = 11-25 y and young adult women > 25 y) for advanced-stage dysgerminoma.

METHODS

The Malignant Germ Cell Tumor International Consortium (MaGIC) pooled data from six GCT trials (3 = pediatric, 3 = adult) conducted internationally by pediatric and gynecologic oncology clinical trial organizations (CTOs) between 1983 and 2009. Newly diagnosed patients, with advanced-stage (FIGO IC-IV) dysgerminoma, who received either carboplatin- or cisplatin-based chemotherapy were eligible for analysis.

RESULTS

126 eligible patients were identified; 56 patients (38 = pediatric, 18 = adult) received carboplatin-based and 70 patients (50 = pediatric, 20 = adult) received cisplatin-based chemotherapy. Mean age was 20 y (range = 6-46 y). The median follow-up was 10.3 y (range = 0.17-21.7 y). The five-year event-free survival (EFS₅) and overall survival (OS₅) was 0.94 (95%CI, 0.88-0.97) and 0.96 (95%CI, 0.91-0.99) respectively. Survival outcomes were comparable between carboplatin-(EFS₅ = 0.96 (95%CI, 0.85-0.99), OS₅ = 0.96 (95%CI, 0.85-0.99)) and cisplatin-(EFS₅ = 0.93 (95%CI, 0.83-0.97), OS₅ = 0.96 (95%CI, 0.87-0.99)) based regimens. Across three age groups, comparison of the EFS₅ (<11 y = 0.1, 11-25 y = 0.91 (95%CI, 0.82-0.96), >25 y = 0.97 (95%CI, 0.81-0.99)) and OS₅ (<11 y = 0.1, 11-25 y = 0.95 (95%CI, 0.87-0.99), >25 y = 0.97 (95%CI, 0.81-0.99)) did not demonstrate any statistically significant differences in outcomes.

CONCLUSIONS

Patients diagnosed with dysgerminoma have an excellent OS, across all ages, even in the context of metastatic disease. Data from three large CTOs supports the investigation of carboplatin-based regimens in the frontline treatment of all patients with advanced-stage dysgerminoma to minimize treatment-related toxicities.

Gonadal dysgenesis is associated with worse outcomes in patients with ovarian nondysgerminomatous tumors: A report of the Children's Oncology Group AGCT 0132 study

PURPOSE

In this report, we characterize the timing and behavior of malignant ovarian germ cell tumors (GCTs) in pediatric patients with dysgenetic gonads compared to those with normal gonadal development.

PATIENTS AND METHODS

Patients from the Children's Oncology Group AGCT0132 with malignant ovarian GCTs were included. Within this population, we sought to identify patients with gonadoblastoma, streak ovaries, or other evidence of gonadal dysgenesis (GD). Patients with malignant GCTs containing one or more of the following histologies-yolk sac tumor, embryonal carcinoma, or choriocarcinoma-were included. Patients were compared with respect to event-free survival (EFS) and overall survival (OS).

RESULTS

Nine patients with GD, including seven with gonadoblastoma (mean age, 9.3 years), were compared to 100 non-GD patients (mean age, 12.1 years). The estimated 3-year EFS for patients with GD was 66.7% (95% CI 28.2-87.8%) and for non-GD patients was 88.8% (95% CI 80.2-93.8%). The estimated 3-year OS for patients with GD was 87.5% (95% CI 38.7-98.1%) and for non-GD patients was 97.6% (95% CI of 90.6-99.4%).

CONCLUSION

Patients presenting with nongerminomatous malignant ovarian GCTs in the context of GD have a higher rate of events and death than counterparts with normal gonads. These findings emphasize the importance of noting a contralateral streak ovary or gonadoblastoma at histology for any ovarian GCT and support the recommendation for early bilateral gonadectomy in patients known to have GD with Y chromosome material. In contrast to those with pure dysgerminoma, these patients may represent a high-risk group that requires a more aggressive chemotherapy regimen.

EGF Receptor and mTORC1 Are Novel Therapeutic Targets in Nonseminomatous Germ Cell Tumors

Germ cell tumors (GCT) are malignant tumors that arise from pluripotent embryonic germ cells and occur in children and young adults. GCTs are treated with cisplatin-based regimens which, while overall effective, fail to cure all patients and cause significant adverse late effects. The seminoma and nonseminoma forms of GCT exhibit distinct differentiation states, clinical behavior, and response to treatment; however, the molecular mechanisms of GCT differentiation are not fully understood. We tested whether the activity of the mTORC1 and MAPK pathways were differentially active in the two classes of GCT. Here we show that nonseminomatous germ cell tumors (NSGCT, including embryonal carcinoma, yolk sac tumor, and choriocarcinoma) from both children and adults display activation of the mTORC1 pathway, while seminomas do not. In seminomas, high levels of REDD1 may negatively regulate mTORC1 activity. In NSGCTs, on the other hand, EGF and FGF2 ligands can stimulate mTORC1 and MAPK signaling, and members of the EGF and FGF receptor families are more highly expressed. Finally, proliferation of NSGCT cells in vitro and in vivo is significantly inhibited by combined treatment with the clinically available agents erlotinib and rapamycin, which target EGFR and mTORC1 signaling, respectively. These results provide an understanding of the signaling network that drives GCT growth and a rationale for therapeutic targeting of GCTs with agents that antagonize the EGFR and mTORC1 pathways. Mol Cancer Ther; 17(5); 1079-89. ©2018 AACR.

DICER1 and Associated Conditions: Identification of At-risk Individuals and Recommended Surveillance Strategies

Pathogenic germline DICER1 variants cause a hereditary cancer predisposition syndrome with a variety of manifestations. In addition to conferring increased cancer risks for pleuropulmonary blastoma (PPB) and ovarian sex cord-stromal tumors, particularly Sertoli-Leydig cell tumor, individuals with pathogenic germline DICER1 variants may also develop lung cysts, cystic nephroma, renal sarcoma and Wilms tumor, nodular hyperplasia of the thyroid, nasal chondromesenchymal hamartoma, ciliary body medulloepithelioma, genitourinary embryonal rhabdomyosarcoma, and brain tumors including pineoblastoma and pituitary blastoma. In May 2016, the International PPB Registry convened the inaugural International DICER1 Symposium to develop consensus testing and surveillance and treatment recommendations. Attendees from North America, Europe, and Russia provided expert representation from the disciplines of pediatric oncology, endocrinology, genetics, genetic counseling, radiology, pediatric surgery, pathology, and clinical research. Recommendations are provided for genetic testing; prenatal management; and surveillance for DICER1-associated pulmonary, renal, gynecologic, thyroid, ophthalmologic, otolaryngologic, and central nervous system tumors and gastrointestinal polyps. Risk for most DICER1-associated neoplasms is highest in early childhood and decreases in adulthood. Individual and caregiver education and judicious imaging-based surveillance are the primary recommended approaches. These testing and surveillance recommendations reflect a consensus of expert opinion and current literature. As DICER1 research expands, guidelines for screening and treatment will continue to be updated. Clin Cancer Res; 24(10); 2251-61. ©2018 AACR.

Risk of second malignant neoplasms in women and girls with germ cell tumors

Background

While an elevated risk of second malignant neoplasms (SMNs) has been observed in men treated for germ cell tumors (GCTs), risk of SMNs have not been quantified in adult women or in girls treated for GCTs.

Patients and methods

One-year survivors of primary GCTs diagnosed between January 1980 and December 2012 were identified from Surveillance, Epidemiology, and End Results (SEER 9) registries. Risk of SMNs was calculated using SEER*Stat.

Results

Among 1507 patients, a total of 47 SMNs were identified. The overall risk of SMNs was not elevated in females overall or in females treated for GCT during adulthood although SMN sites (pancreas, soft tissue, bladder, kidney, and thyroid) and trends were comparable with those in men. There were too few childhood GCT cases with SMNs for further analysis.

Conclusions

Unlike men, women treated for GCTs did not have a statistically significant elevated risk of SMNs [standardized incidence ratio = 1.11; 95% confidence interval (CI) = 0.81-1.47]. The fact that SMNs in women occur in sites similar to those observed in men indicate that long-term follow-up of a larger cohort of females treated for GCT is warranted.

Future cancer research priorities in the USA: a Lancet Oncology Commission

We are in the midst of a technological revolution that is providing new insights into human biology and cancer. In this era of big data, we are amassing large amounts of information that is transforming how we approach cancer treatment and prevention. Enactment of the Cancer Moonshot within the 21st Century Cures Act in the USA arrived at a propitious moment in the advancement of knowledge, providing nearly US$2 billion of funding for cancer research and precision medicine. In 2016, the Blue Ribbon Panel (BRP) set out a roadmap of recommendations designed to exploit new advances in cancer diagnosis, prevention, and treatment. Those recommendations provided a high-level view of how to accelerate the conversion of new scientific discoveries into effective treatments and prevention for cancer. The US National Cancer Institute is already implementing some of those recommendations. As experts in the priority areas identified by the BRP, we bolster those recommendations to implement this important scientific roadmap. In this Commission, we examine the BRP recommendations in greater detail and expand the discussion to include additional priority areas, including surgical oncology, radiation oncology, imaging, health systems and health disparities, regulation and financing, population science, and oncopolicy. We prioritise areas of research in the USA that we believe would accelerate efforts to benefit patients with cancer. Finally, we hope the recommendations in this report will facilitate new international collaborations to further enhance global efforts in cancer control.

Evaluation of the utility of 99m Tc-MDP bone scintigraphy versus MIBG scintigraphy and cross-sectional imaging for staging patients with neuroblastoma

PURPOSE

Accurate staging of neuroblastoma requires multiple imaging examinations. The purpose of this study was to determine the relative contribution of ^99m Tc-methylene diphosphonate (MDP) bone scintigraphy (bone scan) versus metaiodobenzylguanidine scintigraphy (MIBG scan) for accurate staging of neuroblastoma.

METHODS

A medical record search by the identified patients with neuroblastoma from 1993 to 2012 who underwent both MIBG and bone scan for disease staging. Cross-sectional imaging was used to corroborate the scintigraphy results. Clinical records were used to correlate imaging findings with clinical staging and patient management.

RESULTS

One hundred thirty-two patients underwent both MIBG and bone scan for diagnosis. All stage 1 (n = 12), 2 (n = 8), and 4S (n = 4) patients had a normal bone scan with no skeletal MIBG uptake. Six of 30 stage 3 patients had false (+) bone scans. In the 78 stage 4 patients, 58/78 (74%) were both skeletal MIBG(+)/bone scan (+). In 56 of the 58 cases, skeletal involvement detected with MIBG was equal to or greater than that detected by bone scan. Only 3/78 had (-) skeletal MIBG uptake and (+) bone scans; all 3 had other sites of metastatic disease. Five of 78 had (+) skeletal MIBG with a (-) bone scan, while 12/78 had no skeletal involvement by either MIBG or bone scan. In no case did a positive bone scan alone determine a stage 4 designation.

CONCLUSION

In the staging of neuroblastoma, ^99m Tc-MDP bone scintigraphy does not identify unique sites of disease that affect disease stage or clinical management, and in the majority of cases bone scans can be omitted from the routine neuroblastoma staging algorithm.

Family history of cancer in children and adolescents with germ cell tumours: a report from the Children's Oncology Group

Background:

Studies of family history of cancer in paediatric germ cell tumours (GCTs) are few, and none has had sufficient sample size to specifically evaluate family history of GCT.

Methods:

We utilised family history data from a paediatric GCT study to calculate standardised incidence ratios (SIR) for GCT and other cancers using age- and sex-specific incidence rates from the SEER Program.

Results:

This analysis included 7998 relatives of paediatric GCT probands. We observed a higher number of GCT cases than expected in male and female relatives of probands (SIR=2.38, 95% CI 1.25, 3.51 for males; SIR=14.3, 95% CI 0.29, 28.4 for females). Further, we observed a particularly strong SIR for relatives of probands with intracranial GCT (SIR=8.07, 95% CI 3.51, 12.6). The SIR for relatives of probands with ovarian GCT was also elevated but did not reach statistical significance (SIR 4.35, 95% CI 0-9.27). Other notable associations include elevated SIRs for melanoma in male relatives and reduced SIRs for lymphatic/haematologic malignancies in male and female relatives.

Conclusions:

These results support the hypothesis that familial aggregation of GCT occurs in males and females.

DICER1-related Sertoli-Leydig cell tumor and gynandroblastoma: Clinical and genetic findings from the International Ovarian and Testicular Stromal Tumor Registry

BACKGROUND

Ovarian sex cord-stromal tumors (OSCST) include juvenile granulosa cell tumors (JGCT), Sertoli-Leydig cell tumor (SLCT) and gynandroblastoma (GAB) among others. These ovarian sex cord-stromal tumors as well as other tumors including pleuropulmonary blastoma (PPB) may be associated with DICER1 mutations. We sought to describe the clinical and genetic findings from the first 107 individuals enrolled in the International Ovarian and Testicular Stromal Tumor Registry.

METHODS

Medical and family history were obtained for individuals consecutively enrolled in the International Ovarian and Testicular Stromal Tumor Registry. Pathology was centrally reviewed. DICER1 sequencing was performed on blood and tumor tissue.

RESULTS

Of the 107 participants, 49 had SLCT, 25 had JGCT and 5 had GAB. Nearly all (36/37) SLCTs and 4/4 GAB tested had a DICER1 mutation in an RNase IIIb domain hotspot; approximately half of these individuals had a predisposing germline DICER1 mutation. Metachronous SLCTs were seen in 3 individuals with germline DICER1 mutations. Other DICER1-associated conditions were seen in 19% of patients with SLCT or GAB. Three children of women with SLCT were diagnosed with PPB based on genetic testing and clinical screening during the course of this study. All were diagnosed with PPB in its earliest and most curable form (Type I), were treated with surgery alone, and are alive without evidence of disease.

CONCLUSIONS

Recognition of the distinct genetic basis for a group of these tumors improves precise classification in difficult cases and promotes mutation-based screening and early detection.

Ovarian Sex Cord-Stromal Tumors

Ovarian sex cord-stromal tumors are clinically significant heterogeneous tumors that include several pathologic types. These tumors are often found in adolescents and young adults and can present with hormonal manifestations as well as signs and symptoms of a pelvic mass. Serum tumor markers may assist in preoperative diagnosis and surveillance. Several subtypes are associated with genetic predisposition, including those observed in patients with Peutz-Jegher syndrome. Recent studies have elucidated the relationship between Sertoli-Leydig cell tumors and DICER1 mutations. When classified as International Federation of Gynecology and Obstetrics stage Ia, most subtypes may be treated with surgery alone. Higher stage or recurrent tumors have variable prognoses that range from a usually rapid course in poorly differentiated Sertoli-Leydig cell tumor to an often prolonged course in adult granulosa cell tumors. New understanding of the molecular pathogenesis of these tumors may pave the way for novel therapeutics.

Diagnostic Impact of Peritoneal Fluid Cytology in the Setting of Pediatric Uterine Adnexal Biopsy or Resection

Peritoneal fluid sampling has been recommended during surgery to resect an ovarian or fallopian tube mass, particularly for its staging relevance in ovarian carcinoma. Guidelines specifically for children are not well established, partly because of incomplete knowledge of the test characteristics in this age group. We sought to determine whether peritoneal fluid cytology sampling aids in diagnosis or staging of pediatric uterine adnexal masses. Children who underwent adnexal mass biopsy or excision from 1993 to 2014 were identified via archival review. Accompanying peritoneal fluid (washings or ascites) was assessed to determine whether it provided information beyond that in the accompanying surgical pathology specimen. Of 656 patients who underwent adnexal mass resection, 350 had concurrent cytologic sampling of peritoneal fluid. Median age at surgery was 14 years. Adnexal mass histologic examination showed tumors with malignant potential in 54 (8%) patients. Malignancy was identified in 3 cytology specimens (2 dysgerminomas and 1 mixed germ cell tumor). By today's guidelines, the malignant cytology specimens would have upstaged 1 of the 3 patients, and her therapy may not have changed. Cytology findings did not refine the histologic diagnosis in any benign or malignant case. Our findings demonstrated a low rate of malignancy (<1%) in peritoneal washing/ascites samples accompanying resection of a pediatric adnexal mass. Influencing staging or treatment by cytology sampling was rare in our cohort. Our findings provided benchmark data in an area dominated by adult studies. Furthermore, they may guide recommendations for cytologic fluid collection and processing tailored for pediatric populations.

Is surgical resection and observation sufficient for stage I and II sacrococcygeal germ cell tumors? A case series and review

BACKGROUND

Sacrococcygeal teratoma (SCT) is the most common germ cell tumor (GCT) of infancy. Up to 35% of infants may have malignant elements. The standard of care for SCT with malignant elements (SCT-ME) has been surgery and chemotherapy. However, cases where low-stage SCT-ME have been successfully observed following resection have been reported.

PROCEDURE

To better understand the outcomes of low-stage SCT-ME that do not receive chemotherapy, we reviewed SCT pathology reports from five children's hospitals from 1999 to 2009. Information regarding staging workup, tumor markers, treatment, and outcome was collected for patients with stage I or II SCT-ME. An English language literature review was also performed.

RESULTS

Seventy-four SCT were identified: 51 stage I and 23 stage II; 13 (18%) were SCT-ME: 5 stage I and 8 stage II; four stage I and four stage II tumors were not treated with chemotherapy. No stage I tumors recurred; all of the stage II tumors recurred and were successfully salvaged, two had no ME at recurrence. We identified another 10 stage I SCT-ME in the literature managed with active surveillance-two recurred and were successfully treated with surgery and chemotherapy.

CONCLUSIONS

Overall, of the 14 cases of stage I SCT-ME, 12 survived with no recurrence and the two who did recur were successfully treated with platinum-based chemotherapy (EFS = 86%, overall survival [OS] = 100%); this suggests that patients with stage I SCT-ME could be observed after surgery and treated only upon recurrence. Stage II SCT-ME require further study in a clinical trial setting.

Variants in BAK1, SPRY4, and GAB2 are associated with pediatric germ cell tumors: A report from the children's oncology group

Germ cell tumors (GCT) are a rare form of childhood cancer that originate from the primordial germ cell. Recent genome-wide association studies (GWAS) have identified susceptibility alleles for adult testicular GCT (TGCT). We test whether these SNPs are associated with GCT in pediatric and adolescent populations. This case-parent triad study includes individuals with GCT diagnosed between ages 0 and 19. We evaluated 26 SNPs from GWAS of adult TGCT and estimated main effects for pediatric GCT within complete trios (N = 366) using the transmission disequilibrium test. We used Estimation of Maternal, Imprinting and interaction effects using Multinomial modelling to evaluate maternal effects in non-Hispanic white trios and dyads (N = 244). We accounted for multiple comparisons using a Bonferroni correction. A variant in SPRY4 (rs4624820) was associated with reduced risk of GCT (OR [95% CI]: 0.70 [0.57, 0.86]). A variant in BAK1 (rs210138) was positively associated with GCT (OR [95% CI]: 1.70 [1.32, 2.18]), with a strong estimated effect for testis tumors (OR [95% CI]: 3.31 [1.89, 5.79]). Finally, a SNP in GAB2 (rs948662) was associated with increased risk for GCT (OR [95% CI]: 1.56 [1.20, 2.03]). Nominal associations (P < 0.05) were noted for eight additional loci. A maternal effect was observed for KITLG SNP rs4474514 (OR [95% CI]: 1.66 [1.21, 2.28]) and a paternal parent-of-origin effect was observed for rs7221274 (P = 0.00007), near TEX14, RAD51C, and PPM1E. We observed associations between SNPs in SPRY4, BAK1, and GAB2 and GCTs. This analysis suggests there may be common genetic risk factors for GCT in all age groups.

Cost and Cost-Effectiveness of Childhood Cancer Treatment in El Salvador: A Collaborative Budget Model

Abstract 32

Background:

Cure rates for childhood cancer in El Salvador (ES) have increased from 5% in 1991 to 68% today as a result of national and international support. Approximately 200 new cases of pediatric cancer are diagnosed annually in ES—all are treated centrally at the National Children’s Hospital Benjamin Bloom. The cost of childhood cancer treatment in low- and middle-income countries (LMICs), such as ES, has not been well investigated. Such data are integral to inform national childhood cancer treatment plans. We undertook this work to determine the cost of operating a national childhood cancer treatment center in ES and to provide an analytic model framework for similar cost analyses in other LMICs.

Methods:

We conducted a cross-sectional study to evaluate the cost of childhood cancer treatment covered by a collaborative budget model in ES. We calculated costs on the basis of annual cases diagnosed and admitted to National Children’s Hospital Benjamin Bloom, and captured supportive expenses for families that are essential to reducing abandonment. Cost-effective analyses were performed and compared with traditional thresholds.

Results:

Initial estimates indicate an annual total operating budget of $5.3 million to treat 200 new cases annually. When combined with current survival outcomes, this represents a cost-effective model using WHO-CHOICE thresholds.

Conclusion:

Providing the first such comprehensive, institution-based estimate for the cost of treatment of childhood cancer in LMICs, we show that a childhood cancer treatment center represents a cost-effective intervention. This baseline information can be used to prioritize future treatments and interventions in ES. This methodology also allows similar studies to be conducted in other LMICs. Together, these data will inform a case for investment in global access to childhood cancer treatment.

AUTHORS' DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST

Soad Fuentes-Alabi No relationship to disclose Roberto Franklin Vasquez No relationship to disclose Nickhill Bhakta No relationship to disclose Carlos Rodriguez-Galindo Honoraria: Novimmune A. Lindsay Frazier Consulting or Advisory Role: Decibel Therapeutics Rifat Atun No relationship to disclose Sumit Gupta No relationship to disclose Susan Horton No relationship to disclose