Revised risk classification for pediatric extracranial germ cell tumors based on 25 years of clinical trial data from the United Kingdom and United States

Outcomes of pediatric extracranial germ cell tumors: A single center experience in a developing country

The purpose of this study was to analyze the outcomes of extracranial GCT in children in a developing country and to assess prognostic factors. The data on 141 children (<18 years old) with extracranial GCT, confirmed histopathologically, collected over the past 9 years (from February 2013 to June 2022) were retrospectively studied. The patients underwent the same therapy with platinum-containing chemotherapy regimens. In the malignant GCT group, OS and EFS were 81.0 ± 4% and 73 ± 5%, respectively. OS and EFS in the teratoma group were 90 ± 5% and 85 ± 6%. In univariate analysis, parameters like stage of disease, tumor localization, AFP level ≥10,000 ng/mL, serum AFP kinetics and resection status were found to be statistically significant prognostic factors. In the multivariate analysis, the significant adverse factors were the resection status, initial AFP level ≥10,000 ng/mL and serum AFP kinetics slow down (p = .000). Good survival rates can be achieved in developing countries with adequate compliance with treatment protocols. The analysis demonstrates high efficacy of platinum-containing chemotherapy regimens. In our opinion, the protocol used in high-income countries can be implemented in low-income countries with the financial support from the government. The qualification of specialists is also important.

Impact of Surgical Timing (Primary, Delayed, or Second Look) on Surgical Morbidity and Outcomes in Malignant Germ Cell Tumor of the Ovary in Children

BACKGROUND

Malignant ovarian germ cell tumors (MOGCT) are rare in children. Surgery with or without chemotherapy is the primary treatment approach. This study aimed to analyze the impact of primary and delayed surgery on surgical morbidity and outcomes. Second-look surgery after inadequate surgical staging and the various components of surgical staging were also evaluated.

METHODS

Children below 15 years with MOGCT treated between 2006 and 2022 were analyzed. A comparison of patients undergoing primary, delayed, and second-look surgery was performed.

RESULTS

118 patients with a median age of 12 (0.11-15) years were eligible. Forty patients underwent primary, 51 delayed, and 27 second-look surgeries. Overall complications, including tumor rupture, blood loss, and adjacent organ removal, were significantly higher in the primary compared to the delayed surgery group (p = 0.0001). Second-look surgery conceded more blood loss (p = 0.0001), extended duration (p = 0.03), and complications (p = 0.004) than delayed surgery. The compliance with surgical guidelines was 100% for most components, with a positive yield rate of 10-80%. At a median follow-up of 5.2 years, the 5-year event-free survival (EFS) and overall survival (OS) for the entire cohort are 86% and 89%, respectively. The OS and EFS did not differ by the timing of surgery, although the second-look surgery demonstrated relatively inferior outcomes consequential to initial suboptimal surgery.

CONCLUSIONS

MOGCT shows favorable outcomes. Delayed surgery after chemotherapy in appropriately selected patients minimizes the morbidity of surgery with similar outcomes compared to primary surgery. An optimal initial surgery is essential since second-look surgery produces significant morbidity. Prognosis Study, Level II evidence.

Adolescent and Young Adult Germ Cell Tumors: Epidemiology, Genomics, Treatment, and Survivorship

Innovations in the care of adolescent and young adult (AYA) germ cell tumors (GCTs) are needed for one of the most common AYA cancers for which treatment has not significantly changed for several decades. Testicular GCTs (TGCTs) are the most common cancers in 15- to 39-year-old men, and ovarian GCTs (OvGCTs) are the leading gynecologic malignancies in women younger than 25 years. Excellent outcomes, even in widely metastatic disease using cisplatin-based chemotherapy, can be achieved since Einhorn and Donohue's landmark 1977 study in TGCT. However, as the severity of accompanying late effects (ototoxicity, neurotoxicity, cardiovascular disease, second malignant neoplasms, nephrotoxicity, and others) has emerged, efforts to deintensity treatment and find alternatives to cisplatin have taken on new urgency. Current innovations include the collaborative design of clinical trials that accrue GCTs across all ages and both sexes, including adolescents (previously on pediatric trials), and OvGCT (previously on gynecologic-only trials). Joint trials accrue larger sample sizes at a faster rate and therefore evaluate new approaches more rapidly. These joint trials also allow for biospecimen collection to further probe GCT etiology and underlying mechanisms of tumor growth, thus providing new therapeutic options. This AYA approach has been fostered by The Malignant Germ Cell International Consortium, which includes over 115 GCT disease experts from pediatric, gynecologic, and genitourinary oncologies in 16 countries. Trials in development incorporate, to our knowledge, for the first time, molecular risk stratification and precision oncology approaches on the basis of specific GCT biology. This collaborative AYA approach pioneering successfully in GCT could serve as a model for impactful research for other AYA cancer types.

Characterizing Lymphovascular Invasion in Pediatric and Adolescent Malignant Ovarian Nongerminomatous Germ Cell Tumors: A Report from the Children's Oncology Group

BACKGROUND

Lymphovascular invasion (LVI) has been identified as a poor prognostic factor for a variety of tumors; however, its significance in malignant ovarian germ cell tumors (MOGCT) in pediatric and adolescent patients is not well described. We aim to clarify the significance of LVI in the subset of patients with nongerminomatous MOGCT.

METHODS

Records of patients 0-20 years of age with MOGCT enrolled on Children's Oncology Group study AGCT0132 were reviewed. Patients with documented presence or absence of LVI in either institutional or central review pathology reports were included.

RESULTS

Of 130 patients with MOGCTs, 83 patients had of the presence or absence of LVI documented in their pathology report. 42/83 patients (50.6%) were found to have LVI present. The estimated odds of having LVI was higher in patients with stage II and III disease, 11 years and older and with the presence of choriocarcinoma. Event-free survival (EFS) and overall survival (OS) remained high in patients with LVI. Approximately 50% of patients with a documented LVI status in either institutional pathology report or central review were found to have LVI.

CONCLUSIONS

The presence of LVI was higher in tumors with adverse risk factors including higher stage and age greater than 11 years. While LVI was not associated with EFS or OS in the intermediate risk group, further work is necessary to determine the effect of LVI on long-term disease-free survival. We, therefore, recommend routinely incorporating LVI status into institutional pathology reports for pediatric and adolescent patients with MOGCT.

LEVEL OF EVIDENCE

III.

Outcome and late effects of patients treated for childhood vaginal malignant germ cell tumors

PURPOSE

Vaginal malignant germ cell tumors (MGCT) are rare, occurring in children less than 2 years old and raise the question of the optimal local treatment.

METHODS

We included children treated for vaginal MGCT according to the French TGM-95/2013 regimen. Patients were classified as standard risk (SR: localized disease and alpha-fetoprotein (AFP) < 10,000 ng/mL) or high risk (HiR: metastatic and/or AFP > 10,000 ng/mL) and were treated, respectively, with three to five VBP (vinblastine-bleomycin-cisplatin) or four to six VIP (etoposide-ifosfamide-cisplatin), followed by conservative surgery and/or brachytherapy in case of post-chemotherapy residuum.

RESULTS

Fourteen patients were included (median age = 12 months), of which six (43%) were classified as HiR. AFP levels were normalized after first-line chemotherapy in all cases but one. A vaginal post-chemotherapy residuum (median size = 8 mm, range: 1-24 mm) was observed in 13/14 patients, treated by complete resection in seven of 13 (viable cells in three of seven), incomplete resection in four of 13 (viable cells in two of four), with adjuvant brachytherapy in two of 13, and exclusive brachytherapy in two of 13 (viable cells in one of six). Among the six patients with viable disease, four patients received adjuvant chemotherapy. One patient (SR) experienced immediate postoperative relapse despite presenting no viable residual cells and was treated with four VIP cycles and brachytherapy. At last follow-up (median = 4.6 years, range: 0.5-16), all patients were alive in complete remission. Five patients suffered from vaginal sequelae with synechiae and/or stenosis (of whom four had undergone brachytherapy).

CONCLUSION

Childhood vaginal MGCTs show a highly favorable prognosis with risk-adapted chemotherapy and local treatment of post-chemotherapy residuum (preferably by conservative surgery with partial vaginectomy). Brachytherapy could be an alternative when conservative surgery is not deemed possible or in cases of incomplete resection with residual viable cells.

Extracranial Germ Cell Tumors in Children: Ten Years of Experience in Three Children's Medical Centers in Shanghai

OBJECTIVE

The aim was to describe the clinical features of extracranial germ cell tumors (GCTs) in pediatrics and study the clinical risk factors related to survival for malignant germ cell tumors (MGCTs) in order to optimize therapeutic options.

METHODS

The clinical data of children with extracranial GCTs in three children's medical centers in Shanghai were retrospectively analyzed.

RESULTS

In total, 1007 cases of extracranial GCTs diagnosed between 2010 and 2019 were included in this study, including teratomas (TERs) 706 (70.11%) and MGCTs 301 (29.89%). There were twice as many TER cases as MGCT cases. Approximately 50% of children with GCTs were <3 years old (43.39% for TERs, 67.13% for MGCTs). GCTs in children of different ages show differences in tumor anatomical locations and pathological subtypes. The 5-year event-free survival (EFS) and overall survival (OS) of all patients with MGCTs were 82.33% (95% CI, 77.32%, 86.62%) and 94.13% (95% CI, 90.02%, 96.69%), respectively. The multivariate Cox regression analysis identified a primary site in the mediastinum and alpha fetoprotein (AFP) levels ≥10,000 ng/mL as independent adverse prognostic factors (p < 0.0.0001, χ2 = 23.6638, p = 0.0225, χ2 = 5.2072.). There were no significant differences in OS among children receiving various chemotherapy regimens, such as the BEP, PEB, JEB and other regimens (VBP/VIP and AVCP/IEV) (p < 0.05).

CONCLUSIONS

The clinical features of GCTs in Chinese pediatrics are similar to those reported in children in Europe and America. The age distribution of pathological types and primary sites in GCTs reflect the developmental origin of type I and type II GCTs transformed from mismigration primordial germ cells (PGCs). Optimizing the current platinum-based chemotherapy regimens and exploring the treatment strategies for MGCTs of the mediastinum are future research directions.

Critical elements in the operative management of pediatric malignant ovarian germ cell tumors

Performance of the appropriate operation is highly important to ensure that any patient with a suspected ovarian germ cell tumor receives optimal therapy that prioritizes cure while simultaneoulsy minimizing risk of short and long-term toxicities of treatment. The following critical elements of any operative procedure performed for a suspected pediatric or adolescent ovarian germ cell tumor are reviewed: 1. Complete resection of the tumor via ipsilateral oophorectomy while avoiding tumor rupture and spillage, and 2. Performance of complete intraperitoneal staging at the time of initial tumor resection.

Children's Oncology Group's 2023 blueprint for research: Germ cell tumors

Extracranial germ cell tumors (GCT) are a biologically diverse group of tumors occurring in children, adolescents, and young adults. The majority of patients have excellent outcomes, but treatment-related toxicities impact their quality of survivorship. A subset of patients succumbs to the disease. Current unmet needs include clarifying which patients can be safely observed after initial surgical resection, refinement of risk stratification to reduce chemotherapy burden in patients with standard-risk disease, and intensify therapy for patients with poor-risk disease. Furthermore, enhancing strategies for detection of minimal residual disease and early detection of relapse, particularly in serum tumor marker-negative histologies, is critical. Improving the understanding of the developmental and molecular origins of GCTs may facilitate discovery of novel targets. Future efforts should be directed toward assessing novel therapies in a biology-driven, biomarker-defined, histology-specific, risk-stratified patient population. Fragmentation of care between subspecialists restricts the unified study of these rare tumors. It is imperative that trials be conducted in collaboration with national and international cooperative groups, with harmonized data and biospecimen collection. Key priorities for the Children's Oncology Group (COG) GCT Committee include (a) better understanding the biology of GCTs, with a focus on molecular targets and mechanisms of treatment resistance; (b) strategic development of pediatric and young adult clinical trials; (c) understanding late effects of therapy and identifying individuals most at risk; and (d) prioritizing diversity, equity, and inclusion to reduce cancer health disparities and studying the impacts of social determinants of health on outcomes.

Role of Alpha-Fetoprotein (AFP) in Diagnosing Childhood Cancers and Genetic-Related Chronic Diseases

Alpha-fetoprotein (AFP) is a protein commonly found during fetal development, but its role extends beyond birth. Throughout the first year of life, AFP levels can remain high, which can potentially mask various conditions from the neurological, metabolic, hematological, endocrine, and early childhood cancer groups. Although AFP reference values and clinical utility have been established in adults, evaluating AFP levels in children during the diagnostic process, treatment, and post-treatment surveillance is still associated with numerous diagnostic pitfalls. These challenges arise from the presence of physiologically elevated AFP levels, inconsistent data obtained from different laboratory tests, and the limited population of children with oncologic diseases that have been studied. To address these issues, it is essential to establish updated reference ranges for AFP in this specific age group. A population-based study involving a statistically representative group of patients could serve as a valuable solution for this purpose.

Imaging of pediatric ovarian tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Ovarian tumors in children are uncommon. Like those arising in the adult population, they may be broadly divided into germ cell, sex cord, and surface epithelium subtypes; however, germ cell tumors comprise the majority of lesions in children, whereas tumors of surface epithelial origin predominate in adults. Diagnostic workup, including the use of imaging, requires an approach that often differs from that required in an adult. This paper offers consensus recommendations for imaging of pediatric patients with a known or suspected primary ovarian malignancy at diagnosis and during follow-up.

Imaging of pediatric testicular tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper

Primary intratesticular tumors are uncommon in children, but incidence and risk of malignancy both sharply increase during adolescence. Ultrasound is the mainstay for imaging the primary lesion, and cross-sectional modalities are often required for evaluation of regional or distant disease. However, variations to this approach are dictated by additional clinical and imaging nuances. This paper offers consensus recommendations for imaging of pediatric patients with a known or suspected primary testicular malignancy at diagnosis and during follow-up.

Molecular Biology of Pediatric and Adult Ovarian Germ Cell Tumors: A Review

Ovarian germ cell tumors (OGCTs) are rare in adults; indeed, they occur predominantly in children, adolescents, and young adults, and they account for approximately 11% of cancer diagnoses in these groups. Because OGCTs are rare tumors, our current understanding of them is sparse; this is because few studies have investigated the molecular basis of pediatric and adult cancers. Here, we review the etiopathogenesis of OGCTs in children and adults, and we address the molecular landscape of these tumors, including integrated genomic analysis, microRNAs, DNA methylation, the molecular implications of treatment resistance, and the development of in vitro and in vivo models. An elucidation of potential molecular alterations may provide a novel field for understanding the pathogenesis, tumorigenesis, diagnostic markers, and genetic peculiarity of the rarity and complexity of OGCTs.

Pediatric Extracranial Germ Cell Tumors: Review of Clinics and Perspectives in Application of Autologous Stem Cell Transplantation

Pediatric extracranial germ cell tumors (GCTs) are rare, accounting for approximately 3.5% of childhood cancers. Since the introduction of platinum-based chemotherapy, the survival rate of patients has improved to more than 80%. However, poor-risk subtypes of pediatric extracranial GCTs do not respond well to chemotherapy, leading to refractory or relapsed (R/R) diseases. For example, long-term survival rates of mediastinal GCTs or choriocarcinoma are less than 50%. According to reports in recent years for adult patients with R/R GCTs, the use of high-dose chemotherapy (HDCT) combined with autologous stem cell transplantation (ASCT) has clinical advantages; however, HDCT combined with ASCT has rarely been reported in pediatric GCTs. The R/R and poor-risk groups of pediatric GCTs could benefit from HDCT and ASCT.

Extracranial germ cell tumours in children and adolescents: Results from the French TGM13 protocol

BACKGROUND

Chemotherapy for non-seminomatous germ cell tumours (NSGCT) exposes to dose-dependent toxicities. The TGM13-NS protocol (EudraCT 2013-004039-60) aimed to decrease the chemotherapy burden compared to the previous TGM95 protocol while maintaining the 5-year event-free survival (EFS) at 80% or more.

PROCEDURE

Patients less than 19 years of age with disseminated NSGCT were enrolled (May 2014 to May 2019) and stratified into four groups: two intermediate-risk (IR: localised tumour with low tumour markers [TM]) groups treated with VBP (vinblastine-bleomycin-cisplatin): three courses for IR1 (ovarian tumour any age/testis tumour less than or equal to 10 years) and four courses for IR2 (extragonadal tumour 10 years or less) groups, and two high-risk (HR: metastatic and/or high TM) groups treated with etoposide-cisplatin and either ifosfamide (VIP) or bleomycin (BEP): three courses for HR1 (ovarian tumour any age/testis tumour less than or equal to 10 years and low TM/testis tumour more than 10 years and very low TM) groups and four courses for HR2 (remainder) groups.

RESULTS

One hundred fifteen patients were included: median age of 12.8 years (0.4-18.9); tumour sites: 44 ovaries, 37 testes and 34 extragonadal. The 5-year EFS and overall survival (OS) were 87% (95% CI: 80-92) and 95% (89-98), respectively (median follow-up: 3.5 years, range: 0.2-5.9), similar to those of the TGM95 protocol (5-year EFS 89% (84-93), 5-year OS 93% (89-95), p = .561). The 5-year EFS were 93% (95% CI: 80-98), 88% (71-95) and 79% (62-90) for ovarian, testicular and extragonadal tumours, respectively. The 5-year EFS varied (p = .02) according to the risk groups: 90% (66-97), 64% (30-85), 95% (72-99) and 87% (74-94) for IR1, IR2, HR1 and HR2, respectively. TM decline adjusted to tumour site, and alpha-fetoprotein (AFP) level revealed a prognostic impact of time to normalisation on EFS: HR = 1.03 (1.003-1.007).

CONCLUSION

Risk-adapted and globally decreased chemotherapy burden maintains excellent outcomes, exclusive of the IR2 group, which warrants more intensive chemotherapy.

Develop and validate nomogram to predict cancer-specific survival for patients with testicular yolk sac tumors

Purpose

Testicular yolk sac tumor (TYST) is a rare malignant germ cell tumor that mainly occurs in young men. Due to the low incidence of yolk sac tumors, there is a lack of prospective cohort studies with large samples. We aimed to develop a nomogram to predict cancer-specific survival (CSS) in patients with TYST.

Materials and methods

Patient information was downloaded from the Surveillance, Epidemiology and End Results (SEER) database. We enrolled all patients with TYST from 2000 to 2018, and all patients were randomly divided into a training set and a validation set. Univariate and multivariate Cox proportional hazards regression models were used to identify independent risk factors for patients. We constructed a nomogram based on the multivariate Cox regression model to predict 1-, 3-, and 5-year CSS in patients with TYST. We used a series of validation methods to test the accuracy and reliability of the model, including the concordance index (C-index), calibration curve and the area under the receiver operating characteristic curve (AUC).

Results

619 patients with TYST were enrolled in the study. Univariate and multivariate Cox regression analysis showed that age, T stage, M stage and chemotherapy were independent risk factors for CSS. A nomogram was constructed to predict the patient's CSS. The C-index of the training set and the validation set were 0.901 (95%CI: 0.859-0.847) and 0.855 (95%CI: 0.865-0.845), respectively, indicating that the model had excellent discrimination. The AUC showed the same results. The calibration curve also indicated that the model had good accuracy.

Conclusions

In this study, we constructed the nomogram for the first time to predict the CSS of patients with TYST, which has good accuracy and reliability and can help doctors and patients make clinical decisions.

Surgical treatment confers prognostic significance in pediatric malignant mediastinal germ cell tumors

BACKGROUND

Primary malignant mediastinal germ cell tumors (GCTs) are rare pediatric tumors that have a poorer prognosis compared to GCTs occurring elsewhere in the body. The current study aimed to assess the prognostic factors and treatment outcomes of children with primary malignant mediastinal GCT in Taiwan.

METHODS

The authors retrospectively reviewed children 0-18 years old who were newly diagnosed with primary malignant mediastinal GCT between January 1, 2005 and December 31, 2019 and were registered in the Taiwan Pediatric Oncology Group patient registry. The impact of presenting characteristics, including sex, age, tumor stage, histology subtype, surgical treatment, and chemotherapy regimens of the patients were analyzed.

RESULTS

This study enrolled 52 children with malignant mediastinal GCT who had a median age of 16.0 (range, 6.0-17.9) years at diagnosis. The most common histological subtypes were mixed GCTs (n = 20) and yolk sac tumors (n = 15). Advanced disease stage and choriocarcinoma histology subtype were associated inferior outcomes. Children who received surgical treatment exhibited better outcomes compared to those who did not (5-year overall survival, 78% vs. 7%, p < .001). After comparing patients who received first-line cisplatin- and carboplatin-based chemotherapy, no difference in treatment outcomes was observed. Multivariate analysis showed that surgical management was the only independent predictor for superior OS.

CONCLUSIONS

Surgical treatment is recommended for mediastinal GCT. Cisplatin-based chemotherapy was not superior to carboplatin-based chemotherapy as first-line treatment and may be avoided due to toxicity concerns.

Vaginal yolk sac tumor resected by a novel laparo/endoscope-assisted posterior sagittal approach: a case report

Background

Yolk sac tumor (YST) is a germ cell tumor that is generally associated with good prognosis in children. It has been recently reported that vaginal YSTs can be cured using chemotherapy alone. Thus, minimal invasiveness and function preservation are pre-requisites for surgical approaches. Herein, we report a case of vaginal YST that was resected in a function-preserving manner using a unique combination of surgical approaches.

Case presentation

In a 9-month-old Asian female infant, a vaginal tumor was detected while investigating for vaginal bleeding. The patient was referred to our hospital, and the tumor was diagnosed as a YST after incisional biopsy. Six courses of carboplatin-based chemotherapy were administered. Contrary to the findings in previous reports, the tumor was chemo-resistant and surgical resection was required for the residual tumor. During surgery, we utilized laparoscopic and endoscopic procedures to ensure tumor-free surgical margins at the cervix, rectum, and lateral wall of the vagina. Additionally, the posterior sagittal approach was used to easily resect the tumor, and the vagina was reconstructed leaving only inconspicuous scars in the intergluteal cleft. No complications occurred postoperatively. Pathological examination of the surgical specimen revealed tumor-free surgical margins. The patient received four cycles of intensified chemotherapy before and after the surgery. The patient has been disease-free for 6 months now.

Conclusions

Our combination of laparo/endoscopic and posterior sagittal approach ensured a tumor-free macroscopic surgical margin with easier, cosmetically pleasing vaginal reconstruction, while preserving the anorectal and urinary functions. We believe that this approach could be utilized not only for vaginal YST, but also for any vaginal tumor, especially those arising from the posterior or lateral wall.

Outcomes and prognostic variables of extracranial germ cell tumors in children and adolescents treated over a decade: A developing world perspective

BACKGROUND

The purpose of this single-center study was to analyze the outcomes of extracranial germ cell tumors (GCTs) in children treated on a multimodality regimen.

METHODS

Retrospective study of children (<18 years) with a histopathologically confirmed diagnosis of extracranial GCT over a period of 10 years (January 2009 to December 2018) treated on a uniform institution-based protocol consisting of both cisplatin- and carboplatin-based regimens. All completely excised teratomas and stage I gonadal tumors received no further therapy (low risk [LR]); stage IV ovarian, stage III-IV extragonadal GCTs received six cycles of chemotherapy (high risk [HR]), and the remaining received four cycles of chemotherapy (intermediate risk [IR]).

RESULTS

A total of 297 children were treated with a female:male ratio of 1.72:1 and median age of 4 years. Forty-three children had pure teratomas. Gonadal GCTs (N = 180) were more common than extragonadal GCTs (N = 117) with ovary as primary site in 128 children (43%) and sacrococcygeal site being the commonest extragonadal location (N = 41; 14%). LR, IR, and HR disease were noted in 60 (20.2%), 125 (42%), and 112 (37.8%) patients, respectively. Three-fourths of ovarian tumors and half of testicular tumors operated prior to presentation needed upstaging. Forty-one patients relapsed and 43 children expired (disease-related: 33; toxic deaths: 9; unknown: 1). The 5-year event-free survival (EFS)/overall survival (OS) of malignant GCT (n = 254) was 72.50%/82.70%, respectively, with gonadal site (p = .001), LR and IR (p = .001) and nonmetastatic disease (p = .001) being favorable prognostic variables.

CONCLUSIONS

The LR and IR GCTs in our cohort had an excellent outcome. A significant proportion of IR gonadal GCTs can be spared of systemic chemotherapy by adhering to strict surgical guidelines. In HR GCTs however, intensifying therapies to improve outcomes must be balanced against the risk of cumulative toxicity, more so in a resource-limited setting.

Malignant extracranial germ cell tumours: A first national report by the South African Children's Cancer Study Group

OBJECTIVE

To determine the overall survival (OS) and prognostic factors influencing outcomes in children and adolescents with malignant extracranial germ cell tumours (MEGCTs) in preparation for the development of a harmonised national treatment protocol.

METHODS

A retrospective folder review was undertaken at nine South African paediatric oncology units to document patient profiles, tumour and treatment-related data and outcomes for all children with biopsy-proven MEGCTs from birth up to and including 16 years of age.

RESULTS

Between 1 January 2000 and 31 December 2015, 218 patients were diagnosed with MEGCTs. Female sex (hazard ratio [HR] 0.284, p = .037) and higher socio-economic status (SES) (HR 0.071, p = .039) were associated with a significantly lower risk of death. Advanced clinical stage at diagnosis significantly affected 5-year OS: stage I: 96%; stage II: 94.3%; stage III: 75.5% (p = .017) and stage IV (60.1%; p < .001). There was a significant association between earlier stage at presentation and higher SES (p = .03). Patients with a serum alpha-fetoprotein (AFP) level of more than 33,000 ng/ml at diagnosis had significantly poorer outcomes (p = .002). The use of chemotherapy significantly improved survival, irrespective of the regimen used (p < .001).

CONCLUSIONS

The cohort demonstrated a 5-year OS of 80.3% with an event-free survival (EFS) of 75.3%. Stage, the use of chemotherapy and an elevated serum AFP level of more than 33,000 ng/ml were independently predictive of outcome. The relationship between SES and outcome is important as the implementation of the new national protocol hopes to standardise care across the socio-economic divide.

Update on pediatric testicular germ cell tumors

BACKGROUND

Testicular germ cell tumors are uncommon tumors that are encountered by pediatric surgeons and urologists and require a knowledge of appropriate contemporary evaluation and surgical and medical management.

METHOD

A review of the recommended diagnostic evaluation and current surgical and medical management of children and adolescents with testicular germ cell tumors based upon recently completed clinical trials was performed and summarized in this article.

RESULTS

In this summary of childhood and adolescent testicular germ cell tumors, we review the initial clinical evaluation, surgical and medical management, risk stratification, results from recent prospective cooperative group studies, and clinical outcomes. A summary of recently completed clinical trials by pediatric oncology cooperative groups is provided, and best surgical practices are discussed.

CONCLUSIONS

Testicular germ cell tumors in children are rare tumors. International collaborations, data-sharing, and enrollment of patients at all stages and risk classifications into active clinical trials will enhance our knowledge of these rare tumors and most importantly improve outcomes of patients with testicular germ cell tumors.

LEVEL OF EVIDENCE

This is a review article of previously published and referenced level 1 and 2 studies, but also includes expert opinion level 5, represented by the American Pediatric Surgical Association Cancer Committee.

Outcome of pediatric germ cell tumor with comparison of carboplatin and cisplatin based regimens: A 10-year analysis

Carboplatin is being advocated more frequently for treatment of childhood germ cell tumors (GCT), due to less long-term toxicity, and demonstrable equivalence in outcome as compared to cisplatin. This analysis presents the survival of GCT in a low middle-income country and compares two different chemotherapeutic regimens. A retrospective analysis of patient case records was carried out over 10-years (January 2007-December 2016). Chemotherapy regimen used was bleomycin, etoposide, and cisplatin (PEb) for initial 6-½ years and carboplatin, etoposide, and bleomycin (CEb) subsequently. Ninety patients with GCT were treated over 10-years. Malignant GCT was diagnosed in 69 (77%) patients, with 21(23%) having teratoma. The chemotherapy protocol was PEb in 38 (42%), CEb in 28 (31%) patients, while 24 patients were treated with surgery only. Stage 4 tumor was observed in 19 (21%) patients. Relapse or disease progression was seen in 11(12%). Overall and event-free survival at 5-years for the entire cohort was 77% and 73%, being similar with PEb (OS:77%; EFS:72.5%) vs. CEb (OS:69%; EFS: 69%). Significantly better overall survival was noted for patients with gonadal GCT) and non-stage 4 disease, while event-free survival was significantly better in patients with non-stage 4 disease. The chemotherapeutic regimen (PEb vs. CEb), very high AFP (value ≥10,000 IU/L), and risk stratification (low, intermediate, or high-risk disease) did not affect survival significantly. Carboplatin-based strategy was equivalent in our cohort to cisplatin-based strategy, and could be used safely in the LMIC set-up. The overall survival is suboptimal, with delayed presentation, abandonment, and relapse being barriers to survival.

What Should Be the Topics of a Prospective Study on Ovarian Masses in Children?—Results of a Multicenter Retrospective Study and a Scoping Literature Review

Purpose: to determine management problems of ovarian masses in girls in order to form a baseline for prospective randomized studies of the established topics and quality improvement of our management. Materials and Methods: We performed a national analysis of clinical aspects of ovarian masses in girls operated on in Poland, analyzed retrospectively medical files of all consecutive patients aged 0–18 who underwent surgeries for ovarian lesions between 2012 and 2017 at 17 pediatric surgical departments and complemented the analysis with a scoping review of a recent primary research related to ovarian masses in children. Results: The study group comprised 595 patients. Forty-four (7.39%) girls were diagnosed with malignant tumors. The overall preservation rate was 64.54%. The analysis revealed that positive tumor markers (OR = 10.3), lesions larger than 6 cm (OR = 4.17) and solid mass on ultrasound examination (OR = 5.34) are interdependent variables differentiating malignant tumors from non-malignant lesions (X42 = 79.1; p = 0.00000). Our scoping review revealed 10 major branches of research within the topic of ovarian masses in pediatric population. Conclusions: We have developed an overview of the field with the emphasis on the local environment. Our next step is a multi-institutional prospective study of a quality improvement project implementation based on the obtained knowledge.

Pitfalls in the diagnosis of yolk sac tumor: Lessons from a clinical trial

Though outcomes for patients with recurrent/refractory malignant germ cell tumors (mGCTs) are poor, therapies targeting mTOR and EGFR inhibition have shown promise in vitro. We hypothesized that the combination of sirolimus and erlotinib will show activity in patients with recurrent/refractory mGCTs. Patients were enrolled in a prospective phase II clinical trial; central review of existing pathology specimens was performed. Of the five patients evaluated, two had their diagnoses revised to pancreatic acinar cell carcinoma and alpha-fetoprotein (AFP)-secreting gastric adenocarcinoma, respectively. Although mGCTs are common AFP-secreting neoplasms, recurrence or refractoriness to standard regimens should prompt histologic reevaluation for other diagnoses.

Diagnostic, Prognostic and Predictive Markers in Pediatric Germ Cell Tumors—Past, Present and Future

Germ cell tumors (GCTs) are a heterogenous group of neoplasms in children and young adults, in which serum tumor markers have been demonstrated to be highly sensitive diagnostic and monitoring tools. The known "old" serum biomarkers, alpha-fetoprotein (AFP), human choriogonadotropin (β-hCG) and lactate dehydrogenase (LDH), have some limitations in sensitivity and specificity. MIRNAs from the miR-371~373 (chromosomal locus 19q13.41) and miR-302/367 (4q25) clusters are universally over-expressed in malignant GCT tissue samples. The levels of miRNAs from these clusters are elevated in the serum. They seem to be highly sensitive and specific in malignant GCTs diagnosis and disease assessment during treatment and follow-up. The aim of our review was to present the role of serum tumor markers in the clinical staging, treatment monitoring and follow-up of pediatric patients with GCTs and show new possibilities. The serum levels of miRNAs seem to be a new, promising essential tool in the clinical management of GCTs.

Characteristics and outcomes of pediatric testicular yolk Sac tumor

PURPOSE

Pediatric testicular yolk sac tumor is a rare malignant germ cell tumor and there is a lack of large clinical studies. The purpose of this study is to summarize the clinical characteristics of pediatric testicular yolk tumor and evaluate the prognostic factors.

MATERIALS AND METHODS

The medical records of children with testicular yolk sac tumor in one pediatric medical centre in China from January 2005 to January 2021 were retrospectively investigated. Data regarding clinical characteristics, treatment and prognosis were collected.

RESULTS

A total of 109 patients with a median diagnosed age of 18 months (range 2-69) were included in this study; of them 100 were diagnosed as stage I, 6 as stage II and 3 as stage IV. All patients underwent radical orchiectomy, and 61 of them underwent postoperative chemotherapy. The mean follow-up time was 61.3 months (range 3-259), during that time, 8 patients experienced relapse. The five-year overall survival was 90.6% (95% CI 84.6%-96.7%). Univariate Cox regression analysis showed that disease stage, relapse, maximum tumor diameter, and alpha-fetoprotein returning to normal within 2 months postoperatively were risk factors for survival (HRs of 25.43, 26.43, 1.48 and 0.08, respectively, p < 0.05). Multivariate Cox regression analysis suggested that higher disease stage and relapse were independent adverse factors for survival (HRs of 148.30 and 94.58, respectively, p < 0.05).

CONCLUSIONS

The prognosis of pediatric testicular yolk sac tumor is generally excellent. A higher disease stage and the occurrence of relapse could predict a poor prognosis. The individualized management of children with testicular yolk sac tumor according to risk classification is feasible.

Outcome of Postchemotherapy Residual Disease in Extracranial Germ Cell Tumor in Children: Experience of a Tertiary Care Center

OBJECTIVES

The aim was to review outcome with residual disease at the end of first line chemotherapy in patients with extracranial germ cell tumor (GCT) in our resource limited setting.

METHODS

A retrospective analysis of 196 patients with GCT recruited at Shaukat Khanum Memorial Cancer Hospital (SKMCH) from January 2008 to December 2016. Data fields included site, histopathology, stage, risk groups, baseline alpha fetoprotein, beta human chorionic gonadotropin levels, residuum after primary treatment, completeness of surgical excision and outcomes. Data analysis involved quantitative analysis, mean and median calculations, event free survival (EFS) and overall survival (OS) calculations using Kaplan-Meier curves.

RESULTS

In 196 included patients, M:F ratio was 1. There were 81 (41.3%) adolescents. Alpha fetoprotein was >10,000 IU/L in 56 (28.6%) patients. Sixty-two (31.6%) patients had extragonadal disease. Most patients (n=137, 69.9%) presented with advanced stage (III/IV). Seventy-six patients had postchemotherapy residual disease (n=59 [78%] with partial response (PR) and 17 [22%] with no response [NR]). Five-year OS was 83% and EFS was 67%. Five-year EFS of patients with complete remission after primary chemotherapy was 85% versus 70% in patients with PR and 6% in those with NR (P=0.001). OS in patients with complete remission, PR and NR was 94%, 87%, and 46%, respectively. All patients with NR progressed or relapsed and 8/17 died. Four patients with normalized tumor marker response were found to have active tumor on resection of postchemotherapy residuum.

CONCLUSION

Patients with postchemotherapy residual disease in pediatric extracranial GCTs, fare better if their residuum is resected compared with those who do not undergo resection.

Testicular tumors in the pediatric patient

Testicular cancer is a rare malignancy that demonstrates variability in histopathologic features, treatment protocols, and outcomes based on a patient's age at presentation. In the pediatric population, puberty provides an important timestamp for evaluating and understanding the disease process. Prepubertal males, often designated as < 11 years of age, are more likely to present with benign disease. In contrast, the majority of post-pubertal testicular masses are malignant. Other factors, such as race/ethnicity, family history, and personal medical history can influence a patient's risk for malignancy as well. Serum tumor markers (STM) and histologic evaluation are key for diagnosis and for determining management. While normal STMs in a pre-pubertal patient likely qualify a patient for testis-sparing surgery, radical orchiectomy is the gold standard for post-pubertal patients, regardless of STM levels. Cross-sectional imaging is essential for staging and may be done before or after surgical intervention depending on the clinical scenario. Excellent survival outcomes are often achieved regardless of disease risk, with low-stage disease managed safely with surveillance. Surveillance usually consists of STM and imaging monitoring. If adjuvant therapy is indicated, a multi-disciplinary team approach is paramount. This approach should include following pediatric vs. adult protocols based of the patient's pubertal status in order to achieve optimal oncologic outcomes.

Multimodal Treatment of Children With Sacrococcygeal Yolk Sac Tumor: Retrospective Analysis of Clinicopathology Characteristics and Relapse-free Survival

The aim of the study was to explore the clinicopathologic characteristics of sacrococcygeal yolk sac tumor (SYST) associated with relapse and the role of sensitivity to neoadjuvant chemotherapy in predicting outcome. The authors investigated prognostic factors of age, stage, initial tumor size, pathologic response to neoadjuvant chemotherapy, and alfa fetoprotein. A total of 26 patients with SYST were enrolled. Neoadjuvant chemotherapy was administered to 20 cases. Six patients underwent resection as initial therapy. Recurrence occurred in 12 patients. Nine patients with specimens exhibiting no malignant component after chemotherapy did not experience recurrence. By contrast, relapses occurred in 7 of 11 patients with viable residual tumor after neoadjuvant chemotherapy. All relapsed patients still achieved partial remission or complete remission after salvage therapy. Five-year relapse-free survival and overall survival rates were 55.2% and 100%, respectively (median follow-up, 59.5 mo; range, 16 to 155). Patients with complete necrosis after neoadjuvant chemotherapy had a better outcome compared with children with viable residual tumor. Relapse-free survival of pediatric SYSTs in this cohort were still low and warrants the multidisciplinary effort.

Treatment and Survival of Malignant Extracranial Germ Cell Tumours in the Paediatric Population: A Systematic Review and Meta-Analysis

OBJECTIVE

This systematic review and meta-analysis was performed to explore overall survival (OS) and event free survival (EFS) rates internationally over the past two decades and to define specific subgroups with inferior outcomes which may demand different treatment strategies.

METHODS

The search focused on malignant extracranial germ cell tumours (GCTs) in the paediatric population. The initial database search identified 12,556 articles; 32 articles were finally included in this review, comprising a total of 5095 patients.

RESULTS

The studies were heterogeneous, varying from single institution reports to large prospective trials. Older studies, describing eras where non-platinum-based chemotherapy regimens were used, showed clearly worse outcomes. Survival for stage I-II gonadal disease is excellent. On the other hand, patients with an initial alpha-fetoprotein (AFP) > 10,000 ng/mL or kU/L, age > 11 years and stage IV disease confer a survival disadvantage. For testicular disease in particular, lymphovascular invasion and certain histopathological subtypes, such as embryonal carcinoma (EC) and mixed malignant GCTs, survival is poorer. Survival data for sacrococcygeal and mediastinal GCTs show a heterogeneous distribution across studies in this review, independent of year of publication. Patients > 12 years presenting with a mediastinal GCT pose a subpopulation which fares worse than GCTs in other locations or age groups. This is independent of AFP levels, stage of disease or treatment protocol, and these patients may demand a different treatment strategy.

CONCLUSIONS

This review describes the heterogeneous nature of GCTs in different anatomical locations, impacting on stage at presentation, treatment modalities used and survival data. Despite this heterogeneity, in line with the current developmental biology-based classification system, subpopulations can be defined which have an inferior EFS and OS and where future research and more individualised treatment would help to improve survival.

Childhood ovarian nonseminomatous germ cell tumors: A highly curable disease with few long-term treatment-related toxicities-Results of the French TGM95 study

We report survival and late effects analysis of TGM95 study for childhood (≤18 years) ovarian nonseminomatous germ cell tumors (NS-GCT). Patients with localized tumors (FIGO-stage IA) had no adjuvant treatment (low-risk, LR). Patients with advanced-stage received 3-5 VBP (vinblastin-bleomycin-cisplatin) in intermediate-risk group (IR: FIGO-stage IC-II-III and AFP < 15 000 ng/mL) or 4-6 VIP (etoposide-ifosfamide-cisplatin) in high-risk group (HiR: metastatic or AFP ≥ 15 000 ng/mL). Seventy-seven patients were included (median age = 12 years): 14 LR (13 FIGO-stage IA, 1 retrospectively IC), 26 IR (12 IC, 12 II-III, 2 not-available) and 37 HiR (2 IA with AFP ≥ 15 000 ng/mL, 27 II-III, 8 IV). After a median follow-up of 13.4 years, 12 events (eight relapses) and six deaths (two GCT-related, two due to acute myeloid leukemia and two noncancer related) occurred. All relapses (6 LR, 1 IR) occurred within 2 years. Four contralateral mature teratomas were observed within 8 years. Five-year EFS and OS were 88.2% (95%CI = 79-94%) and 94.6% (95%CI = 87-98%). Seven patients (9%) had bilateral gonadectomy. Among 51 survivors at 2 years aged >15 years (median = 26 years) with remaining ovarian tissue, all had developed spontaneous puberty and 21 (41%) had at least one pregnancy (including two with infertility treatment). Among 69 patients treated with platinum-based chemotherapy, chronic-kidney-disease was diagnosed in four patients (three after VIP) and significant ototoxicity occurred in three (all grade-2). Childhood ovarian NS-GCTs have an excellent prognosis with few late effects. The low-intensive etoposide-free VBP regimen could be an alternative in children with IR disease especially in cases of tumor rupture. The risk of contralateral mature teratoma needs regular monitoring of the remaining ovary.

Neonatal Malignant Disorders: Germ Cell Tumors

Germ cell tumors (GCTs) comprise a wide spectrum of benign and malignant tumors. Neonatal GCTs are predominantly teratomas (mature or immature), which are typically cured with surgery alone. Relapses are infrequent even in the setting of microscopic residual disease; therefore, negative surgical margins at the cost of significant morbidity are not recommended. In neonates with metastatic malignant disease or malignant disease for which upfront surgical resection is not feasible without significant morbidity, an initial biopsy followed by neoadjuvant chemotherapy and delayed surgical resection is recommended. Carboplatin-based regimens should be considered when chemotherapy is indicated.

Malignant sacrococcygeal germ cell tumors in childhood: The Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) experience

PURPOSE

To evaluate clinical features at diagnosis, prognostic factors, and outcomes of malignant sacrococcygeal germ cell tumors (SC-GCTs) in patients enrolled in the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) TCG 2004 protocol.

PATIENTS AND METHODS

A prospective analysis was conducted on all consecutive patients diagnosed with malignant SC-GCTs between January 2004 and May 2017. Patients with stage I underwent surgery and subsequent surveillance, the others received pediatric cisplatinum-etoposide-bleomycin (pPEB) regimen and eventual deferred surgery.

RESULTS

Of 45 patients, 35 were females. Age at diagnosis ranged from 1 day to 3.6 years (median 1.6 years); 26 were stage IV. Of 38 patients who underwent surgery, pathology revealed yolk sac tumor (YST) in 27 and teratoma + YST/embryonal carcinoma in 11, while seven patients were diagnosed based on imaging and elevated levels of alpha-fetoprotein (AFP). Of six patients approached with surgery, only one relapsed and was rescued with first-line chemotherapy. Overall, 38 out of 45 achieved complete remission, three a partial remission, and four were resistant. Ten out of 41 patients who entered remission later relapsed and nine were rescued with a second-line treatment. We observed a global failure percentage of 31% and a 5-year overall survival (OS) and event-free survival (EFS) of 95% and 69%, respectively.

CONCLUSIONS

Chemotherapyis generally effective in malignant SC-GCTs, even though almost one-third of our patients experienced events salvageable with second-line treatment. Most of the relapses occurred within 1 year from diagnosis. A close follow up with serial AFP level monitoring should be done for at least 2 years after diagnosis.

Management of Germ Cell Tumors in Pediatric Patients

Germ cell tumors arise from primordial germ cells. Most develop in the gonads or along midline structures of the body. Genetic aberrations leading to disruption in the molecular signaling responsible for primordial germ cell migration early in development may provide rationale for why germ cell tumors originate in extragonadal locations. Establishing best practices for treating pediatric germ cell tumors remains an area of active investigation. Recent advances focused on limiting toxicities of therapy, identifying new therapies for relapsed and refractory tumors, defining best practices for surgical staging and resection, and developing novel methods to monitor for disease relapse.

Burned-Out Testicular Tumors in Adolescents: Clinical Aspects and Outcome

Purpose: Testicular germ cell tumors are the fourth most common neoplasm in adolescents, accounting for 8% of all tumors in the age group 15-19 years. On rare instances, the primary testicular lesion is not clinically or radiologically evident while nodal or visceral metastases represent the clinical manifestations of the disease. This phenomenon is described as "burned-out testicular tumor." In this paper, the authors report a single-institution experience with burned-out testicular tumors in adolescents and discuss their clinical implications. Patients and Methods: All the patients diagnosed with metastatic testicular germ cell tumors at Bambino Gesù Children Hospital between January 1, 2010, and June 30, 2020, were included in the study. Patients were categorized into two groups: "primary testicular" and "burned out." All the patients were staged and treated according to the AIEOP-TCGM 2004 protocol. Results: Eleven patients were classified as "primary testicular," and five patients were classified as "burned out." "Burned-out" tumors were associated with the presence of systemic symptoms compared to "primary testicular" tumors (80 vs. 0%; p = 0.0027) and higher aFP, hCG, and LDH levels (p < 0.00001). The "burned-out" population had a statistically significant higher incidence of relevant toxicity than the "primary testicular" population (80 vs. 18%; p = 0.0357) and a worse outcome in terms of both mean overall survival (15 vs. 43 months; p = 0.0299) and mean event-free survival (12 vs. 38 months; p = 0.0164). Conclusion: "Burned-out" testicular tumors seem to be a well-distinct clinical entity with a high treatment-related toxicity and poor prognosis. Further studies are needed to clarify the "burned-out phenomenon" and to identify more effective therapeutic strategies for these patients.

Risk-adapted treatment reduced chemotherapy exposure for clinical stage I pediatric testicular cancer

BACKGROUND

Different from adult clinical stage I (CS1) testicular cancer, surveillance has been recommended for CS1 pediatric testicular cancer. However, among high-risk children, more than 50% suffer a relapse and progression during surveillance, and adjuvant chemotherapy needs to be administered. Risk-adapted treatment might reduce chemotherapy exposure among these children.

METHODS

A decision model was designed and calculated using TreeAge Pro 2011 software. Clinical utilities such as the relapse rates of different groups during surveillance or after chemotherapy were collected from the literature. A survey of urologists was conducted to evaluate the toxicity of first-line and second-line chemotherapy. Using the decision analysis model, chemotherapy exposure of the risk-adapted treatment and surveillance strategies were compared based on this series of clinical utilities. One-way and two-way tests were applied to check the feasibility.

RESULTS

In the base case decision analysis of CS1 pediatric testicular cancer, risk-adapted treatment resulted in a lower exposure to chemotherapy than surveillance (average: 0.7965 cycles verse 1.3419 cycles). The sensitivity analysis demonstrated that when the relapse rate after primary chemotherapy was ≤ 0.10 and the relapse rate of the high-risk group was ≥ 0.40, risk-adapted treatment would result in a lower exposure to chemotherapy, without any association with the proportion of low-risk patients, the relapse rate of the low-risk group, the relapse rate after salvage chemotherapy or the toxicity utility of second-line chemotherapy compared to first-line chemotherapy.

CONCLUSIONS

Based on the decision analysis, risk-adapted treatment might decrease chemotherapy exposure for these high-risk patients, and an evaluation after orchiectomy was critical to this process. Additional clinical studies are needed to validate this statement.

What recent primary studies tell us about ovarian teratomas in children: a scoping review

Our knowledge of ovarian teratomas in children is still far from complete, and much remains to be discovered. Here, we conduct a scoping review of the primary research related to ovarian teratomas in pediatric age. To our knowledge, there is no published synthesis of the literature surrounding ovarian teratomas in children using scoping review methodology. We identified 24 studies from 11 countries; 18 studies were retrospective, 3 were prospective, and 3 were experimental. There were 6 studies concerning mature teratomas, 5 concerning immature teratomas, and 13 that included both tumor types. Overall, 9 out of all the studies concerned more than 50 patients. We revealed 7 major branches of research within the topic of ovarian teratoma in pediatric population: recurrence rate/relapse and follow-up strategy, malignant potential, prognostic factors, use of sparing surgery, differences between the use of laparoscopy and laparotomy, use of chemotherapy, and additional examinations to test the character of the lesion (immature vs. mature). This scoping review has revealed a number of knowledge gaps in the evidence base for pediatric ovarian teratomas. Overall, this topic has not been extensively explored, and more research dedicated exclusively to this tumor and patient population is required.

Outcomes of adolescent males with extracranial metastatic germ cell tumors: A report from the Malignant Germ Cell Tumor International Consortium

BACKGROUND

Adolescents with extracranial metastatic germ cell tumors (GCTs) are often treated with regimens developed for children, but their clinical characteristics more closely resemble those of young adult patients. This study was designed to determine event-free survival (EFS) for adolescents with GCTs and compared them with children and young adults.

METHODS

An individual patient database of 11 GCT trials was assembled: 8 conducted by pediatric cooperative groups and 3 conducted by an adult group. Male patients aged 0 to 30 years with metastatic, nonseminomatous, malignant GCTs of the testis, retroperitoneum, or mediastinum who were treated with platinum-based chemotherapy were included. The age groups were categorized as children (0 to <11 years), adolescents (11 to <18 years), and young adults (18 to ≤30 years). The study compared EFS and adjusted for risk group by using Cox proportional hazards analysis.

RESULTS

From a total of 2024 individual records, 593 patients met the inclusion criteria: 90 were children, 109 were adolescents, and 394 were young adults. The 5-year EFS rate was lower for adolescents (72%; 95% confidence interval [CI], 62%-79%) than children (90%; 95% CI, 81%-95%; P = .003) or young adults (88%; 95% CI, 84%-91%; P = .0002). The International Germ Cell Cancer Collaborative Group risk group was associated with EFS in the adolescent age group (P = .0020). After adjustments for risk group, the difference in EFS between adolescents and children remained significant (hazard ratio, 0.30; P = .001).

CONCLUSIONS

EFS for adolescent patients with metastatic GCTs was similar to that for young adults but significantly worse than for that children. This finding highlights the importance of coordinating initiatives across clinical trial organizations to improve outcomes for adolescents and young adults.

LAY SUMMARY

Adolescent males with metastatic germ cell tumors (GCTs) are frequently treated with regimens developed for children. In this study, a large data set of male patients with metastatic GCTs across different age groups has been built to understand the outcomes of adolescent patients in comparison with children and young adults. The results suggest that adolescent males with metastatic GCTs have worse results than children and are more similar to young adults with GCTs. Therefore, the treatment of adolescents with GCTs should resemble therapeutic approaches for young adults.

The individualized significance of lymphadenectomy across all age groups and histologies in malignant ovarian germ cell tumors

PURPOSE

To evaluate the therapeutic role of lymphadenectomy on patients with malignant ovarian germ cell tumor (MOGCT) and to investigate the risk factors of lymph node metastasis.

METHODS

Patients of MOGCT between 1988 and 2013 with definite lymph node information were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Survival curves were estimated using the Kaplan-Meier method, and Cox regression analyses were performed to evaluate the effects of clinical and pathologic variables on survival.

RESULTS

2424 MOGCT patients with information on lymph nodes were included. Of the entire cohort, 46.2% patients received lymphadenectomy. The most common (42.2%) histologic type was teratoma, and 70.6% patients had FIGO stage I disease. Cox proportional model verified that age, grade, and log odds of positive lymph nodes (LODDS) were independent prognostic factors. Subgroup analysis showed that the association between the lymph node resection and better survival in the different age cohort.

CONCLUSIONS

Lymphadenectomy is not recommended for children (0-14 years). For patients 40 years of age and older, and for those who have the dysgerminoma type or endodermal sinus type, lymphadenectomy had an outstanding therapeutic role. As a parameter to assess lymph node status, LODDS could be used to classify MOGCTs.

Surgical resection and outcome of malignant ovarian germ cell tumors in children-a national multicentric study compared to international results

PURPOSE

To evaluate the outcome of pediatric malignant ovarian germ cell tumors treated by three tertiary Egyptian institutions, and to compare our national experience to internationally published data.

METHODS

This is a retrospective analysis of all patients presenting between September 2014 and September 2019. Management protocol was Children's Oncology Group (COG) in all participating centers. Overall survival (OS), event-free survival (EFS) and univariate prognostic factors were estimated by Kaplan-Meier and log-rank test. Additionally, a review of various practices that reported survival outcome was conducted.

MAIN RESULTS

Thirty-seven patients were included with a median age of 10.5 years (1-18 years). Thirty-five patients had unilateral salpingo-oophorectomy. Mixed germ cell and yolk sac tumors represented 75.7% of patients. There were 7 (19%), 14 (37.8%), 12 (32.4%) and 4 (10.8%) stage I, II, III and IV, respectively. Seven patients were low risk (LR), 26 intermediate risk (IR) and 4 high risk (HR). Platinum-based chemotherapy was administered as per risk stratification. Follow-up to March 2020 revealed that five patients had relapsed. There were no statistical significances of pathological types and patients' age regarding OS (p value 0.392 and 0.281, respectively) and EFS (p value 0.420 and 0.437, respectively). Three-year OS was 84%: 100% for stages I and II, and 62% for stages III and IV (p = 0.003); 100% for LR, 89% for IR, and 24% for HR (p < 0.001). Three-year EFS was 87%: 96% for stages I and II, and 71% for stages III and IV (p = 0.025); 100% for LR, 92% for IR, and 26% for HR (p < 0.001).

CONCLUSION

Surgical resection combined with chemotherapy achieves excellent outcome for such tumors in both, present study and previous reports. On the basis of our results, COG staging and risk stratification were significantly correlated with prognosis, whereas tumor pathology and age had no significant impact. Prognostic factors are controversial among studies, and further research is still required.

Germ Cell Tumors in Adolescents and Young Adults

Germ cell tumors (GCTs) are rare in childhood, representing only 3.5% of childhood cancers, but a common malignancy in adolescents and young adults (AYAs), accounting for 13.9% of neoplasms in adolescents between age 15 and 19 years. The overall outcomes of patients treated for GCTs are excellent. However, as seen in other cancers, outcomes for AYA patients are significantly worse. Understanding the reasons for this observation has led to different approaches to diagnosis, staging, and treatment. The Malignant Germ Cell International Consortium was created to bring together pediatric, gynecologic, and testicular cancer specialists to promote research initiatives and provide evidence-based approaches in the management of GCTs across different age groups. Collaboration between multiple subspecialties is essential to further understand the disease continuum, the underlying biologic characteristics, and the development of appropriate therapeutic approaches. This review focuses on the unique characteristics of patients with extracranial GCTs in the AYA group.

Development of a Data Model and Data Commons for Germ Cell Tumors

Germ cell tumors (GCTs) are considered a rare disease but are the most common solid tumors in adolescents and young adults, accounting for 15% of all malignancies in this age group. The rarity of GCTs in some groups, particularly children, has impeded progress in treatment and biologic understanding. The most effective GCT research will result from the interrogation of data sets from historical and prospective trials across institutions. However, inconsistent use of terminology among groups, different sample-labeling rules, and lack of data standards have hampered researchers' efforts in data sharing and across-study validation. To overcome the low interoperability of data and facilitate future clinical trials, we worked with the Malignant Germ Cell International Consortium (MaGIC) and developed a GCT clinical data model as a uniform standard to curate and harmonize GCT data sets. This data model will also be the standard for prospective data collection in future trials. Using the GCT data model, we developed a GCT data commons with data sets from both MaGIC and public domains as an integrated research platform. The commons supports functions, such as data query, management, sharing, visualization, and analysis of the harmonized data, as well as patient cohort discovery. This GCT data commons will facilitate future collaborative research to advance the biologic understanding and treatment of GCTs. Moreover, the framework of the GCT data model and data commons will provide insights for other rare disease research communities into developing similar collaborative research platforms.

Survival differences by race/ethnicity among children and adolescents diagnosed with germ cell tumors

Survival differences by racial and ethnic group have been reported in children and adolescents with germ cell tumors (GCTs), but whether these differences depend on stage of disease is unclear. Using the SEER 18 registries (2000-2015), we examined GCT survival differences by race/ethnicity (non-Hispanic white [NHW], Black, Asian/Pacific Islander [API], Hispanic) separately for males and females aged 0-19 years at diagnosis. We used Kaplan-Meier survival curves (Log-Rank p values) to characterize survival differences. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI) for the association between race/ethnicity and death. Using an inverse odds weighting mediation analysis, we estimated the association between race/ethnicity and death treating stage of disease as the mediator. There were no significant racial/ethnic survival differences among females. Male survival differed by race/ethnicity (p < 0.0001) with NHW males having the best survival. Compared to NHW, API and Hispanic males had significantly higher risks of death (API HR: 2.18; 95% CI: 1.32-3.56; Hispanic HR: 1.98; 95% CI: 1.42-2.78) (model adjusted for age and year at diagnosis, tumor histology and location, stage). This association was mediated by stage of disease only among Hispanic males with gonadal tumors (indirect HR: 1.18; 95% CI: 1.03-1.35). The increased risk of death after a testicular GCT diagnosis observed among Hispanic males was mediated by stage of disease. For API males and Hispanic males with extragonadal tumors, other unidentified factors including differences in exposures, tumor biology or treatment received may impact the observed racial/ethnic survival disparities.

Age-Dependent Presentation and Clinical Course of 1465 Patients Aged 0 to Less than 18 Years with Ovarian or Testicular Germ Cell Tumors; Data of the MAKEI 96 Protocol Revisited in the Light of Prenatal Germ Cell Biology

OBJECTIVE

To evaluate prognostic factors in pediatric patients with gonadal germ cell tumors (GCT).

METHODS

Patients <18 years with ovarian and testicular GCT (respectively OGCT and TGCT) were prospectively registered according to the guidelines of MAKEI 96. After resection of the primary tumor, patients staged ≥II received risk-stratified cisplatin-based combination chemotherapy. Patients were analyzed in respect to age (six age groups divided into 3-year intervals), histology, stage, and therapy. The primary end point was overall survival.

RESULTS

Between January 1996 and March 2016, the following patients were registered: 1047 OGCT, of those, 630 had ovarian teratoma (OTER) and 417 had malignant OGCT (MOGCT); and 418 TGCT, of those, 106 had testicular teratoma (TTER) and 312 had malignant TGCT (MTGCT). Only in MTGCT, older age correlated with a higher proportion of advanced tumors. All 736 teratomas and 240/415 stage I malignant gonadal GCT underwent surgery and close observation alone. In case of watchful waiting, the progression rate of OGCT was higher than that of TGCT. However, death from disease was reported in 8/417 (1.9%) MOGCT and 8/312 (2.6%) MTGCT irrespective of adjuvant chemotherapy and repeated surgery.

CONCLUSIONS

The different pathogenesis and histogenesis of gonadal GCT reflects sex- and age-specific patterns that define clinically relevant risk groups. Therefore, gender and age should be considered in further research on the biology and clinical practice of pediatric gonadal GCT.

Multicenter pre-operative assessment of pediatric ovarian malignancy

PURPOSE

The purpose of this study was to develop a pre-operative risk assessment tool for childhood and adolescent ovarian malignancy, in order to guide operative management of pediatric ovarian masses.

METHODS

We conducted a retrospective analysis of patients <18 years old who underwent ovarian surgery at two quaternary care pediatric centers over 4 years (1/1/13-12/31/16). Probability of malignancy was estimated based on imaging characteristics (simple cyst, heterogeneous, or solid), maximal diameter, and tumor markers (α-fetoprotein, β-human chorionic gonadotropin).

RESULTS

Among 188 children with ovarian masses, 11% had malignancies. For simple cysts, there were no malignancies (0/24, 95% CI = 0-17%). Among solid lesions, 44% (15/34, 95% CI = 28-62%) were malignant. Among marker-elevated heterogeneous masses, 40% (2/5, 95% CI = 12-77%) were malignant. Conversely, small (≤10 cm) and large (>10 cm) marker-negative heterogeneous lesions had malignancy proportions of 0% (0/39, 95% CI = 0-11%) and 5% (2/40, 95% CI = 1-18%), respectively.

CONCLUSIONS

Given the malignancy estimates identified from these multi-institutional data, we recommend an attempt at ovarian-sparing resection for simple cysts or tumor marker-negative heterogeneous lesions ≤10 cm. Oophorectomy is recommended for solid masses or heterogeneous lesions with elevated markers. Finally, large (>10 cm) heterogeneous masses with non-elevated markers warrant a careful discussion of ovarian-sparing techniques. Complete surgical staging is mandatory regardless of operative procedure.

TYPE OF STUDY

Study of Diagnostic Test.

LEVEL OF EVIDENCE

Level I.

Interventions for cisplatin-induced hearing loss in children and adolescents with cancer

The identification of preventive interventions that are safe and effective for cisplatin-induced ototoxicity is important, especially in children because hearing loss can impair speech-language acquisition development. Previous randomised trials assessed systemic drugs such as amifostine, sodium diethyldithiocarbamate or disulfiram, and sodium thiosulfate. Amifostine, sodium diethyldithiocarbamate, and disulfiram did not show hearing preservation. Paediatric trials assessing sodium thiosulfate showed efficacy in terms of hearing protection. The SIOPEL 6 trial consisted solely of patients with localised hepatoblastoma and no effects on survival were shown. In the ACCL0431 trial, which included heterogeneous patients, a post-hoc analysis showed significantly worse overall survival among patients who had disseminated disease receiving sodium thiosulfate than among controls, but not among those with localised disease. Intratympanically administered drugs have mainly been assessed in adults and include N-acetylcysteine and dexamethasone. Inconsistent effects of these drugs were identified but these studies were limited by design, small sample size, and statistical approach. Future studies of systemic drugs will need to consider the measurement of disease outcomes through study design and sample size, and ototoxicity endpoints should be harmonised to enhance comparability between trials.