α‐Fetoprotein as a predictor of outcome for children with germ cell tumors: A report from the Malignant Germ Cell International Consortium

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.

Excellent Outcomes in Children, Adolescents, and Young Adults with Ovarian Germ Cell Tumors Treated by Either Reduced- or Standard-Dose Bleomycin

To investigate the outcomes of children, adolescents, and young adults (AYAs) with malignant ovarian germ cell tumors (MOGCTs), we analyzed the data of 61 patients aged ≤39 years diagnosed with MOGCT between 2006 and 2022. Among 59 patients who received chemotherapy after initial diagnosis, 57 received BEP (standard dose of bleomycin with 30 units per week, n = 13) or bEP (reduced dose of bleomycin with 15 units/m2 on day 1, n = 44). The 5-year overall survival (OS) and event-free survival (EFS) rates were 98.3% and 84.9%, respectively. Reduced bleomycin dose did not adversely affect survival. Normalization of tumor markers within 3 months after surgery was significantly associated with better EFS (p < 0.01). Of the 59 surviving patients, 8 experienced surgery-related menopause, while 49 demonstrated menstrual recovery. After completion of chemotherapy, there was no significant difference in pulmonary function regarding bleomycin dose, and no overt nephrotoxicity. Approximately 60% and 25% of survivors experienced peripheral neuropathy at the end of chemotherapy and after 1 year, respectively (p < 0.01). Children and AYAs with MOGCT have favorable survival rates with minimal long-term toxicity, which are not influenced by a reduced bleomycin dose. Rapid normalization of tumor markers is associated with improved 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.

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.

A Paper-Based Photoelectrochemical Sensing Platform Based on In Situ Grown ZnO/ZnIn2S4 Heterojunctions onto Paper Fibers for Sensitively Detecting AFP

Nowadays, developing a cost-effective, easy-to-operate, and efficient signal amplification platform is of important to microfluidic paper-based analytical devices (μPAD) for end-use markets of point-of-care (POC) assay applications. Herein, an ultrasensitive, paper-based photoelectrochemical (PEC) bioassay platform is constructed by in situ grown ZnO/ZnIn₂S₄ heterojunctions onto paper fibers, which acted as photoactive signal amplification probes for enhancing the sensitivity of antibodies-based diagnostic assays, for the sensitive detection of alpha-fetoprotein (AFP) targets. The crystalline flake-like ZnIn₂S₄ composited with hexagonal nanorods (NRs) morphology of ZnO is an in situ grown, at the first time, onto cellulose fibers surface supported with Au nanoparticle (Au NP) modification to improve conductivity of the device working zone. The obtained composites on paper fibers are implemented as a flexible paper-based photoelectrode to realize remarkable performance of the fabricated μPAD, resulting from the enhanced PEC activity of heterojunctions with effective electron-hole pair separation for accelerating photoelectric conversion efficiency of the sensing process under light irradiation. Once the target AFP was introduced into the biosensing interface assistant, with a specific recognition interaction of AFP antibody, a drastically photocurrent response was generated, in view of the apparent steric effects. With the concentration increase of AFP targets, more immune conjugates could be confined onto the biosensing interface, eventually leading to the quantitative decrease of photocurrent intensity. Combined with an ingenious origami design and permitting the hydrophobic/hydrophilic conversion procedure in the bioassay process, the ultrasensitive PEC detection of AFP targets was realized. Under the optimized conditions, the level of AFP could be sensitively tracked by the prepared μPAD with a liner range from 0.1 to 100 ng mL^-1 and limit of detection of 0.03 ng mL^-1. This work provides a great potential application for highly selective and sensitive POC testing of AFP, and finally, developments for clinical disease diagnosis.

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.

Early Decline of Neuron-Specific Enolase during Neuroblastoma Chemotherapy is a Predictive Factor of Clinical Outcome

High risk neuroblastoma (HR-NB) remains one of the most difficult-to-treat pediatric cancers. However, although current risk-stratification is based on multiple pretreatment criteria, HR-NB remains a significant heterogeneity. We examined 60 patients with HR-NB for a median follow-up time of 28 months. We examined the serum neuronspecific enolase (NSE) levels of each chemo cycle, using the survival receiver operating characteristic (survivalROC) method to assess the prognostic power of NSE levels at variant chemo points. We demonstrated that serum NSE was associated with systemic tumor burden. NSE after the third chemo cycle (C3) (C3NSE) was significantly higher in patients who eventually showed cancer relapse or progression. C3NSE had independent prognostic significance for event-free survival (EFS) but not for overall survival (OS) in multivariate cox analysis. SurvivalROC prompted that the C3NSE is a prognostic marker of HR-NB, which had good discrimination for 2- and 3-year EFS with AUC 0.734 and 0.729, respectively. However, its prognositc value for 2- and 3- year OS declined progressively. C3 is the optimal point to predict EFS. Patients whose C3 serum NSE remain at higher level need to undergo more intensive treatment as early as possible to resist recurrence.

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.