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

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.

Clinical characteristics of malignant germ cell tumors in adolescents: A multicenter 10-year retrospective study in Beijing

Background

The aim of this study was to review clinical features of adolescent malignant germ cell tumors (MGCTs) in Beijing and analyze the peculiar characteristics of this age group.

Methods

Clinical characteristics, pathological presentations, and survival outcomes of 34 patients were analyzed retrospectively.

Results

Of 34 patients, 12 girls and 22 boys, 18 (52.9%) had an extra-cranial tumor, including one testicular tumor, five ovarian tumors, one sacrococcygeal tumor, and 11 mediastinal tumors. Histologically, we found immature teratomas (n = 6), yolk sac tumors (n = 5), mixed malignant tumors (n = 5), an embryonic carcinoma (n = 1), and seminoma (n = 1). Three-year event-free survival (EFS) and overall survival (OS) were 48.8% and 62.9%, respectively. Another 16 (47.1%) patients had an intracranial tumor, including nine in the pineal region, five in the suprasellar region, one in basal ganglia, and one in cerebellopontine. All patients had localized disease and an excellent outcome with 3-year EFS and OS of 93.7% and 100%, respectively.

Conclusions

Adolescent MGCTs are rare with a strong dependence on gender, and the mediastina and pineal region are the most common tumor locations. The prognosis is promising compared with that of other adolescent tumors and MGCTs in other age groups. MGCTs in mediastina have a tendency to companion with other hematological malignancies, and the prognosis is extremely poor in these patients.

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.

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.

Cisplatin-induced ototoxicity: a novel approach to an ancient problem

With the scarcity of pharmacological otoprotective agents against cisplatin-induced ototoxicity (CIO), researchers find themselves compelled to look at and navigate all possible strategies to identify ways to prevent CIO. One of these promising strategies is pharmacogenomic implementation. This strategy aims for identifying and detecting high-risk genetic variants to tailor cisplatin therapy to reach the best survival outcomes with the least risk of ototoxicity.

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.

Fertility and prognosis assessment between bleomycin/etoposide/cisplatin and paclitaxel/carboplatin chemotherapy regimens in the conservative treatment of malignant ovarian germ cell tumors: a multicenter and retrospective study

OBJECTIVE

To evaluate the impact of bleomycin/etoposide/cisplatin (BEP) and paclitaxel/carboplatin (PC) chemotherapy regimens on the fertility and prognostic outcomes in malignant ovarian germ cell tumor (MOGCT) patients who underwent fertility-sparing surgery (FSS).

METHODS

A propensity score matching algorithm was performed between the BEP and PC groups. The χ² test and the Kaplan-Meier method were used to compare the fertility outcome, disease-free survival (DFS) and overall survival (OS). The Cox proportional hazards regression analysis was used to identify risk factor of DFS.

RESULTS

We included 213 patients, 185 (86.9%) underwent BEP chemotherapy, and 28 (13.1%) underwent PC chemotherapy. The median age was 22 years (range, 8-44 years), and the median follow-up period was 63 months (range, 2-191 months). Fifty-one (29.3%) patients had a pregnancy plan, and 35 (85.4%) delivered successfully. In the before and after propensity score matching cohorts, there were no significant differences in spontaneous abortion, selective termination of pregnancy, during-pregnancy status, and live birth between the BEP and PC groups (p>0.05). Fourteen (6.6%) patients experienced recurrence, including 11 (5.9%) in the BEP group and 3 (10.7%) in the PC group. Four (1.9%) patients in the BEP group died. Kaplan-Meier analysis revealed no significant differences in DFS (p=0.328) and OS (p=0.446) between the BEP and PC groups, and the same survival results were observed in the after matching cohort.

CONCLUSION

The PC regimen is as safe as the BEP regimen for MOGCT patients with fertility preservation treatment, and no differences were observed in fertility and clinical prognosis.

Balancing efficacy with long-term side-effects: can we safely de-escalate therapy for germ cell tumors?

INTRODUCTION

The success in the management of germ cell tumors has encouraged researchers to pay more attention on long-term side effects and other survivorship issues. The de-escalation of treatment is intended to reduce side effects but must be balanced against any compromise of efficacy. Cisplatin-based therapy is the cornerstone of treatment for germ cell tumors. However, they can result in acute and long-term side effects, including ototoxicity, neurotoxicity, nephrotoxicity, and increased risk of second malignancies.

AREAS COVERED

This review discusses approaches of de-escalation including biomarker-directed treatment using microRNAs, surveillance for immature teratoma, the use of carboplatin monotherapy for seminoma, and the option of non-cisplatin-based approaches in relapsed germ cell tumors.

EXPERT OPINION

While the results with the current standard options in terms of cancer control are very good, the price being paid in terms of long-term side effects is considerable.

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.

Carboplatin-induced renal salt-wasting syndrome in pediatric patients with intracranial germ cell tumors and concomitant diabetes insipidus

We report a case series of 14 children with intracranial germ cell tumor and concomitant central diabetes insipidus, who developed hyponatremia secondary to renal salt-wasting syndrome (RSWS) following the administration of carboplatin. Clinicians prescribing platinum-based chemotherapy for this group of patients should be alert to the risk of RSWS. Regular monitoring should be performed as hyponatremia can be asymptomatic until it is severe.

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.

New aspects and innovations in the local treatment of renal and urogenital pediatric tumors

Local treatment plays a key role for patients' outcome in tumors of the urogenital tract in children. Despite a great variety of different etiologies, the specific localization of pediatric urogenital tumors renders several characteristic demands to the treating personnel. Surgery and radiotherapy are the main elements of local treatment in this group of neoplasms. Numerous new guidelines and innovative technical developments of surgery and radiotherapy have recently been integrated into treatment concepts for pediatric urogenital tumors. Due to the broadness of the field it is not possible to give a full overview over all aspects. Therefore, this article highlights the most important innovations and new guidelines of surgery and radiotherapy of pediatric urogenital tumors.

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.

Surveillance Only for High-risk FIGO Stage IA/IB Malignant Ovarian Germ Cell Tumors: Results From a National Cancer Database

OBJECTIVES

Investigate the use and outcomes of a surveillance only strategy for patients with high-risk stage I malignant ovarian germ cell tumors.

METHODS

Patients with International Federation of Gynecology and Obstetrics stage IA/IB grade 2 or 3 immature teratoma, yolk sac, or mixed germ cell tumor diagnosed between 2004 and 2014 who had at least 1 month of follow-up were drawn from the National Cancer Database. Overall survival (OS) was evaluated for each histologic subtype using Kaplan-Meier curves, and compared with the log-rank test.

RESULTS

A total of 497 patients were identified; 115 (23.1%) with grade 2 immature teratoma, 157 (31.6%) with grade 3 immature teratoma, 101 (20.3%) with yolk sac tumor, 124 (25%) with mixed germ cell tumor. Rate of adjuvant chemotherapy was 68.2% (655 patients), while rate of lymph node biopsy/dissection was 55.2%. A total of 19 (3.8%) deaths were observed at a median of 29.8 months. There was no difference in OS between patients who did and did not receive adjuvant chemotherapy with grade 2 (P=0.35) and grade 3 immature teratoma (P=0.47) or mixed germ cell tumors (P=0.55). Patients with yolk sac tumors those who received chemotherapy had better OS compared with those who did not, P=0.019; 5-year OS rates were 92.7% and 79.6%, respectively.

CONCLUSIONS

A surveillance only strategy for patients with stage I malignant ovarian germ cell tumors is associated with excellent survival outcomes for patients with grade 2 or 3 immature teratoma or mixed germ cell tumors.

Molecular Biology of Pediatric and Adult Male Germ Cell Tumors

Simple Summary

Although testicular germ cell tumors (TGCTs) are rare pediatric malignancies, they are the most common malignancies in young adult men. The similarities and differences between TGCTs in adults and children, taking into account the clinic presentation, biology, and molecular changes, are underexplored. In this paper, we aim to provide an overview of the molecular aspects of TGCTs, drawing a parallel between the findings in adult and pediatric groups.

Abstract

Cancer is a leading cause of death by disease in children and the second most prevalent of all causes in adults. Testicular germ cell tumors (TGCTs) make up 0.5% of pediatric malignancies, 14% of adolescent malignancies, and are the most common of malignancies in young adult men. Although the biology and clinical presentation of adult TGCTs share a significant overlap with those of the pediatric group, molecular evidence suggests that TGCTs in young children likely represent a distinct group compared to older adolescents and adults. The rarity of this cancer among pediatric ages is consistent with our current understanding, and few studies have analyzed and compared the molecular basis in childhood and adult cancers. Here, we review the major similarities and differences in cancer genetics, cytogenetics, epigenetics, and chemotherapy resistance between pediatric and adult TGCTs. Understanding the biological and molecular processes underlying TGCTs may help improve patient outcomes, and fuel further investigation and clinical research in childhood and adult TGCTs.

Current Insights into Interethnic Variability in Testicular Cancers: Population Pharmacogenetics, Clinical Trials, Genetic Basis of Chemotherapy- Induced Toxicities and Molecular Signal Transduction

Testicular cancer is an aggressive malignancy with a rising incidence rate across the globe. Testicular germ cell tumors are the most commonly diagnosed cancers, and surgical removal of the testes is often a radical necessity along with chemotherapy and radiotherapy. While seminomas are receptive to radiotherapy as well as chemotherapy, non-seminomatous germ cell tumors respond to chemotherapy only. Due to the singular nature of testicular cancers with associated orchiectomy and mortality, it is important to study the molecular basis and genetic underpinnings of this group of cancers across male populations globally. In this review, we shed light on the population pharmacogenetics of testicular cancer, pediatric and adult tumors, current clinical trials, genetic determinants of chemotherapy-induced toxicity in testicular cancer, as well as the molecular signal transduction pathways operating in this malignancy. Taken together, our discussions will help in enhancing our understanding of genetic factors in testicular carcinogenesis and chemotherapy-induced toxicity, augment our knowledge of this aggressive cancer at the cellular and molecular level, as well as improve precision medicine approaches to combat this disease.

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.

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.

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.

Gallic acid potentiates the apoptotic effect of paclitaxel and carboplatin via overexpression of Bax and P53 on the MCF-7 human breast cancer cell line

Despite advances in treatment, breast cancer remains the widest spread disease among females with a high mortality rate. We investigated the potential effects of gallic acid (GA) as supportive therapy in the management of breast cancer. Anti-cancer activity with GA alone or in combination with paclitaxel and/or carboplatin was assessed by MTT assay and flow cytometry using annexin V/propidium iodide. The mechanism underlying the antiproliferative effects was investigated by measuring the expression of the pro-apoptotic marker (Bax), CASP-3, anti-apoptotic (Bcl-2), and, tumor suppressor (p53) by real-time polymerase chain reaction (RT-PCR) and western blot analysis. Cell cycle analysis was performed for the MCF-7 breast cancer cell line. GA, paclitaxel, and carboplatin alone or in combination arrested cell cycle progression at the G2/M phase and induced Pre-G1 apoptosis. RT-PCR showed that the triplet combination significantly raised P53, Bax, and CASP-3 mRNA expression (20.1 ± 1.41, 16.6 ± 0.43, and 20.04 ± 1.61, respectively) in MCF-7 cells when compared to single or combined treatment (p < .0001) while anti-apoptotic Bcl-2 mRNA levels were decreased in all treated groups compared to untreated cells. Western blot data of tested apoptotic factors were consistent with RT-PCR results. For the first time, we show that a minimum non-toxic concentration of GA increased the efficacy of paclitaxel- and carboplatin-induced MCF-7 apoptotic cell death.

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.

Comparative gonadotoxicity of the chemotherapy drugs cisplatin and carboplatin on prepubertal mouse gonads

The treatment of childhood cancer with chemotherapy drugs can result in infertility in adulthood. Newer generations of drugs are developed to replace parent drugs, with the potential benefits of less toxic side effects. For platinum alkylating-like drugs, in contrast to the parent compound cisplatin, the newer-generation drug carboplatin is reported to have reduced toxicity in some respects, despite being administered at 5-15 times higher than the cisplatin dose. Whether carboplatin is also less toxic than cisplatin to the reproductive system is unknown. Here we compare the gonadotoxic impact of cisplatin and carboplatin on female and male mouse prepubertal gonads. In vitro cultured CD1 mouse ovaries or testis fragments were exposed to either cisplatin or carboplatin for 24 h on Day 2 of culture and analysed by Day 6. A dose response for each drug was determined for the ovary (0.5, 1 & 5 μg/ml cisplatin and 1, 5 & 10 μg/ml carboplatin) and the testis (0.01, 0.05 & 0.1 μg/ml cisplatin and 0.1, 0.5 & 1 μg/ml carboplatin). For the ovary, unhealthy follicles were evident from 1 μg/ml cisplatin (73% unhealthy, P = 0.001) and 5 μg/ml carboplatin (84% unhealthy, P = 0.001), with a concomitant reduction in follicle number (P = 0.001). For the testis, the proliferating germ cell population was significantly reduced from 0.05 μg/ml cisplatin (73% reduction, P = 0.001) and 0.5 μg/ml carboplatin (75% reduction, P = 0.001), with no significant impact on the Sertoli cell population. Overall, results from this in vitro animal model study indicate that, at patient equivalent concentrations, carboplatin is no less gonadotoxic than cisplatin.

The impact of cooperative group studies on childhood cancer: Improving outcomes and quality and international collaboration

The advances in pediatric cancer far exceed those achieved in adults. The success in improving survival and minimizing late effects has been due to several reasons but work of the pediatric cancer cooperative groups is a primary. These cooperative groups are multidisciplinary with medical oncologists, pathologists, radiologists, surgeons, radiation oncologists, scientists and most importantly the patients and families. Studies have expanded from regional to national and now international studies which continue to target problems pertinent to improving the outcome for children with cancer. In this article we review the history of the cooperative groups, a selection of seminal studies pertaining to solid tumors, future challenges and collaborations.

AYA testis cancer: The unmet challenge

Testis cancer is considered a rare-incidence cancer but comprises the third most common cancer diagnosed within the adolescent and young adult (AYA) years (15-39 years). Most testis cancer patients can anticipate a survival outcome in excess of 95%. However, there are subgroups of AYA patients where outcomes are considerably worse, including younger adolescents, patients with certain histological subtypes, or from certain ethnic backgrounds. For those cured with chemotherapy, the toxicity of treatment and burden of late effects is significant. Newer germ cell tumor-specific biomarkers may identify patients who do not require further treatment interventions or may detect early recurrence, potentially reducing the burden of treatment required for cure. An international collaboration for this rare tumor is creating the forum for trial design, where these biomarker research questions are embedded. Going forward, AYA testis cancer patients could benefit from having a more personalized treatment plan, tailored to risk, that minimizes the overall burden of late effects.

Effect of Gallic acid in potentiating chemotherapeutic effect of Paclitaxel in HeLa cervical cancer cells

Background

Cervical cancer is the fourth most common cancer affecting women worldwide. Paclitaxel/Carboplatin is one of the most commonly prescribed regimens in cervical cancer treatment. Although chemotherapeutic drugs are very effective, severe side effects and development of drug resistance limits the use of these drugs. The use of natural products with anticancer activity may help to partially overcome these issues.

Methods

In the present study, we investigated the ability of Gallic acid, to potentiate the anti-cancer effects of Paclitaxel, Carboplatin and Paclitaxel/Carboplatin combination in human HeLa cells by performing MTT assay, cell cycle analysis and RT-PCR assay and Western blotting for some apoptotic markers.

Results

Our results revealed that the highest cytotoxic effect, the highest induction of apoptosis and significant elevation in P53 and Caspase 3 levels was seen in Paclitaxel/Gallic acid combination.

Conclusion

These results indicate that Gallic acid potentiates Paclitaxel effect and that Paclitaxel/Gallic acid combination could represent a promising alternative with lower side effects-for Paclitaxel/Carboplatin combination in treatment of cervical cancer treatment.

Fundamental problems with pediatric adaptive dosing of carboplatin using nuclear-medicine-based estimates of renal function

BACKGROUND

Carboplatin is often adaptively dosed based on glomerular filtration rate (GFR), usually estimated by nuclear medicine tests. At least five pediatric adaptive dosing formulas have been developed. In an effort to standardize dosing in Children's Oncology Group protocols, we explored methodologic variation in GFR estimation and adaptive-dosing formula performance.

PROCEDURE

Nuclear medicine GFR data from published series of ≥100 children with cancer were compared. Data from patients for whom body surface area, weight, GFR, and tracer half-life were available were used to compare formulas.

RESULTS

Differences in methods used to estimate GFR in children with cancer resulted in highly variable population results, with median GFRs ranging from 96 to 150 mL/min/1.73m² . The choice of adaptive formula had a major impact on calculated dose. When targeting an area under the curve of 7.9 mg/mL • min, the median difference between the formula yielding the lowest and highest carboplatin dose for individual subjects was 289 (range 96-1 737) mg/m² .

CONCLUSIONS

Wide variation in GFR obtained with nuclear-medicine-based tests in children with cancer primarily results from systematic methodologic errors. Formulas for calculating carboplatin dose produce additional and substantial variation that may place children with cancer at unnecessary risk for excessive toxicity or underdosing. These findings indicate a need for the development of a uniform, validated method for GFR determination in children that should be utilized in all centers. Currently, adaptive dosing of carboplatin based on GFR has serious limitations and in most clinical settings should arguably not be used in place of body-surface-area-based dosing.

Factors that impact the outcomes in testicular germ cell tumors in low-middle-income countries

Germ cell tumors (GCTs) are one of the most common tumors in adolescents and young adults. There is paucity of data on GCT from low-middle-income countries (LMIC). The present study was conducted to assess the demographic features, clinical manifestations, pathology, and outcomes of GCT patients treated at our center. Patients with testicular GCT above the age of 18 years, treated at our center from 2001 to 2015 were included in the study. Data were extracted retrospectively from the case records. Event-free survival (EFS) and overall survival (OS) were calculated using the Kaplan-Meier method and the variables were compared using the log-rank test. The study included 421 patients among whom 128 (30%) had a histological diagnosis of seminoma and 293 (70%) had non-seminomatous germ cell tumor (NSGCT). Metastatic disease at presentation was observed in 83/128 (65%) with seminoma and 254/293 (87%) with NSGCT. According to the International Germ Cell Cancer Collaborative Group (IGCCCG) risk stratification for metastatic disease, good- and intermediate-risk seminoma were observed in 55/83 (66%) and 28/83 (34%) patients, respectively, and good-, intermediate-, and poor-risk NSGCT were observed in 82/254 (32%), 76/254 (30%), and 96/254 (38%) patients, respectively. The median follow-up was 32.3 months (range 0.03-200 months). The 3-year OS for the entire cohort was 80.3%. The 3-year OS for seminoma was 91.4%, and for NSGCT was 75.3%. Factors significantly associated with inferior EFS and OS on multivariate analysis included poor performance status, scrotal orchidectomy, carboplatin-based regimen, NSGCT histology, and treatment default. Patients with testicular GCT in India present in an advanced stage and higher IGCCCG risk compared to Western data. Factors unique to LMIC like treatment default, bulky disease, dose compromise, and scrotal orchidectomy have a negative impact on the outcome.

Carboplatin prodrug conjugated Fe3O4 nanoparticles for magnetically targeted drug delivery in ovarian cancer cells

The magnetically targeted NPs@carboplatin can act as a drug delivery system and will have great potential in ovarian cancer therapeutic applications.