Prognostic value of tumor size, metastases, extension into bone, and increased tumor marker in children with malignant sacrococcygeal germ cell tumors: a prospective evaluation of 71 patients treated in the German cooperative protocols Maligne Keimzelltumoren (MAKEI) 83/86 and MAKEI 89

Potential biomarkers for the early detection of bone metastases

The clinical manifestations of bone metastases are diversified while many sites remain asymptomatic at early stage. As the early diagnosis method is not perfect and the early symptoms of tumor bone metastasis are not typical, bone metastasis is not easy to be detected. Therefore, the search for bone metastasis-related markers is effective for timely detection of tumor bone metastases and the development of drugs to inhibit bone metastases. As a result, bone metastases can only be diagnosed when symptoms are found, increasing the risk of developing skeletal-related event (SREs), which significantly impairs the patient's quality of life. Therefore, the early diagnosis of bone metastases is of great importance for the treatment and prognosis of cancer patients. Changes of bone metabolism indexes appear earlier in bone metastases, but the traditional biochemical indexes of bone metabolism lack of specificity and could be interfered by many factors, which limits their application in the study of bone metastases. Some new biomarkers of bone metastases have good diagnostic value, such as proteins, ncRNAs, circulating tumor cells (CTCs). Therefore, this study mainly reviewed the initial diagnostic biomarkers of bone metastases which were expected to provide references for the early detection of bone metastases.

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.

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.

Sacrococcygeal teratomas in newborns: a comprehensive review for the radiologists

Sacrococcygeal teratomas are the most common solid tumor in newborn infants. The diagnosis is not difficult in many cases; however, there should be additional information on imaging studies in order to manage those infants properly. Details include histology, morphologic classification, complications such as rupture, bleeding, and mass effects on the adjacent structures. Although imaging features cannot accurately predict the histologic subtypes of the tumors, thorough evaluation of the imaging features can help distinguish malignant tumors from benign tumors. In this article, pathogenesis, histological characteristics, clinical considerations, and morphologic characteristics will be discussed.

Malignant Sacrococcygeal Germ Cell Tumors in Children: A 30-year Experience from a Single Institution

Background

Our aim was to analyze treatment results and survival characteristics of our patients with malignant sacrococcygeal germ cell tumors.

Procedure

Patient files of children with malignant sacrococcygeal germ cell tumors, treated at our institution between 1979 and 2009, were searched. Patient characteristics, histopathological subtypes, extension of disease, alpha-fetoprotein (AFP) level at the time of diagnosis and relapse, extent of surgical resection, chemotherapy protocols, details of radiotherapy and survival characteristics were recorded.

Results

A total of 58 patients (M/F = 20/38) with malignant sacrococcygeal germ cell tumor was included in analysis. With a mean follow-up of 156 months (range, 26 days to 288.8 months) overall and event-free survival rates of the 58 patients were 50.9% and 43.8%, respectively. AFP status of the patients (37% in patients with <10,000 ng/ml, 68.9% in patients with ≥10,000 ng/ml), type of resection (total vs others), coccygeal resection, chemotherapy protocol (PEB vs others) and number of chemotherapy courses had an impact on event-free survival in univariate analysis. In multivariate analysis, AFP status had the greatest effect on prognosis.

Conclusions

Our treatment results are worse than those reported in the literature. Elevated AFP level at the time of diagnosis had a beneficial effect on prognosis, but year of diagnosis, tumor stage, presence of metastasis, tumor size and histopathological subtype had no impact on survival in patients with malignant sacrococcygeal germ cell tumors.

Pediatric Germ Cell Tumor: Case Study

Germ cell (yolk sac) tumors are rare tumors that often have a poor prognosis because they are not usually found until metastases have occurred. The diagnosis of yolk sac tumors is usually a multimodality diagnosis in conjunction with a biopsy of the lesion. This case study outlines the initial stages of diagnosing and treating a 22-month-old male patient who was found to have a widespread malignant yolk sac tumor in his abdominopelvic cavity. Sonography was used as the primary imaging modality due to the patient’s age, but it was soon determined that a follow-up with computed tomography was necessary. Because of the complicated nature and progression of the tumor, a surgical biopsy was then performed. During the procedure, it was also noted that the mass was hypervascular with extensive blood flow throughout the mass. Excision was not an option and chemotherapy treatment was recommended.

Yolk sac tumor in the abdominal wall of an 18-month-old girl: a case report

Background

Pediatric germ cell tumors account for approximately 3.5 % of all childhood cancers for children under the age of 15 years. Up to one-third are extragonadal neoplasms. Germ cell tumors are a heterogeneous group of malignant tumors with a wide variety of histopathological features. Yolk sac tumor is the predominant variant in newborns and younger children. We report for the first time, the presentation of a primary yolk sac tumor in the abdominal wall of a small child.

Case presentation

An 18-month-old white girl underwent resection of a small, round subcutaneous lump (1.5×1.3×0.8 cm) of the abdominal wall in her right hypochondriac region. The histopathology was compatible with yolk sac tumor. Her alpha-fetoprotein was initially elevated but normalized after the resection. Magnetic resonance imaging of her abdomen was normal. The surgeon decided to observe and follow her alpha-fetoprotein level closely. One year after resection a local recurrence appeared and her alpha-fetoprotein rose to 58 ng/mL. The surgeon performed a wide resection of the lesion with normalization of her alpha-fetoprotein. Follow-up consisted of measuring alpha-fetoprotein, clinical evaluation, and abdominal ultrasound.

Conclusions

Clinicians should be aware that a yolk sac tumor can present in an unusual extragonadal place, for example in this case it was subcutaneous. In some cases, conservative treatment can be carried out with careful monitoring of the patient and their alpha-fetoprotein.

Evaluation of chemotherapeutic sequelae and quality of life in survivors of malignant sacrococcygeal teratoma

PURPOSE

The impact of chemotherapeutic sequelae on long-term quality of life (QoL) for survivors of malignant sacrococcygeal teratoma (SCT) is unknown. The incidence of chemotherapeutic toxicity in patients treated for malignant SCT and possible effects on the QoL were analyzed.

METHODS

Retrospective chart review of patients ≥18 years treated for SCT in the Netherlands was performed. Present QoL was evaluated using the SF-36 questionnaire. The results of survivors of malignant SCT were compared to those of patients treated for benign SCT.

RESULTS

Fifty-one of 76 traceable patients consented to participate. The results of 47 (92.2 %), 9 men and 38 women (median age 25.4 years, range 18.3-41.2), were analyzed. Eleven had been treated for malignancy; 63.6 % suffered from at least one chemotherapeutic sequel with hearing loss as the most common one. Results for both groups were similar on all but one SF-36 subcategory; those treated for malignant tumor scored significantly lower on the subcategory physical functioning (p = 0.02).

CONCLUSION

Despite the high incidence of chemotherapeutic sequelae among survivors of malignant SCT, their QoL does not differ from that of those treated for benign SCT. Even though their physical functioning is restricted, daily activities and psychosocial functioning of survivors of malignant SCT are not restricted.

Prognostic factors in children with extracranial germ cell tumors treated with cisplatin-based chemotherapy

Purpose

To evaluate the outcomes and prognostic factors in children with extracranial germ cell tumors (GCTs) treated at a single institution.

Methods

Sixty-six children diagnosed with extracranial GCTs between 1996 and 2012 were included in the study. Primary treatment was surgical excision, followed by six cycles of cisplatin-based chemotherapy. The survival rates were compared according to the International Germ Cell Cancer Cooperative Group classification used for GCTs in adults to validate the classification guidelines for GCTs in children.

Results

The median patient age was 4.4 years. In 34 patients (51.5%), the primary tumor site was the gonad. Extragonadal GCTs were detected in 32 patients. The 5-year overall survival and event-free survival (EFS) were 92.0%±3.5% and 90.4%±3.7%, respectively. In univariate analysis, tumor histology, metastasis, and elevated alpha-fetoprotein were not prognostic factors in children with extracranial GCTs. However, EFS was poorer in patients with mediastinal disease (n=12, 66.7%±13.6 %) than in those with nonmediastinal disease (n=54, 96.0%±2.8%) (P=0.001). The 5-year EFS was lower in patients older than 10 years, (n=21, 80.0%±8.9%) compared with those younger than 10 years (n=45, 95.2%±3.3%) (P=0.04). Multivariate analysis identified the mediastinal tumor site as the only independent prognostic factor.

Conclusion

The prognosis of children with extracranial GCTs was favorable. However, nongerminomatous mediastinal tumors were associated with poor survival in children. Further research is needed to improve the prognosis of children with malignant mediastinal GCTs.

Refractory sacrococcygeal germ cell tumor in Schinzel-Giedion syndrome

We describe a boy with Schinzel-Giedion syndrome who developed refractory sacrococcygeal germ cell tumor with elements of embryonal carcinoma and immature teratoma. He developed local recurrence soon after tumor resection. The tumor was highly resistant to platinum-based combination chemotherapy, local irradiation, and salvage chemotherapy. Frequent infections resulted in a delay in treatment, although apparent fragility had not been observed clinically. He died from tumor progression at 32 months of age. Intensification of chemotherapy does not seem to be feasible for tumors in patients with Schinzel-Giedion syndrome.

Regional deep hyperthermia for salvage treatment of children and adolescents with refractory or recurrent non-testicular malignant germ-cell tumours: an open-label, non-randomised, single-institution, phase 2 study

BACKGROUND

Although the survival of children and adolescents with malignant germ-cell tumours has improved greatly in recent years, the outcome remains poor for those with refractory or recurrent malignant germ-cell tumours. We aimed to determine whether objective tumour response could be achieved in patients with refractory or recurrent malignant germ-cell tumours with PEI-regional deep hyperthermia as salvage treatment.

METHODS

Patients with refractory or recurrent non-testicular malignant germ-cell tumours after standard cisplatin-based chemotherapy were treated prospectively with PEI chemotherapy (cisplatin 40 mg/m(2), delivered intravenously on days 1 and 4; etoposide 100 mg/m(2), intravenously on days 1-4; and ifosfamide 1800 mg/m(2), intravenously on days 1-4) plus simultaneous 1-h regional deep hyperthermia (41-43°C) on days 1 and 4. Patients received three to four treatment courses at 21-day intervals until residual tumour resection was possible; they subsequently received one or two additional courses of PEI-regional deep hyperthermia. Local radiotherapy was given for incompletely resected tumours. Chemotherapy and hyperthermia toxic effects were assessed using WHO grading. The primary endpoint was the proportion of patients who had an objective response as assessed with Response Evaluation Criteria in Solid Tumors version 1.0 guidelines. Secondary endpoints were the event-free survival and overall survival after 5 years. This ongoing PEI-regional deep hyperthermia study (Hyper-PEI protocol) is registered at the German Cancer Society, number 50-2732.

FINDINGS

44 patients aged 7 months to 21 years (median 2 years 7 months) with refractory or recurrent malignant germ-cell tumours (nine patients with poor response, 23 patients with first relapse, 12 patients with multiple relapses) were included in this study. We identified 34 yolk sac tumours, eight embryonal carcinomas, one choriocarcinoma, and one dysgerminoma by histology analysis. Of the 35 patients who had sufficient clinical and radiographical data available for response assessment, 30 (86%) had an objective response to treatment (16 patients had complete remission and 14 had partial remission). 5-year event-free survival was 62% (95% CI 45-75), and 5-year overall survival was 72% (95% CI 55-83). The median follow-up of surviving patients was 82 months (range 9-195). WHO grade 3-4 neutropenia and thrombocytopenia occurred in all 181 chemotherapy cycles. Granulocytopenic fever, which required intercurrent hospital admission, was noted in 29 (66%) of 44 patients after 53 (29%) of 181 courses. Five patients experienced treatment-related grade-3 acute renal toxic effects.

INTERPRETATION

A multimodal strategy integrating PEI-regional deep hyperthermia and tumour resection with or without radiation can successfully treat children and adolescents with refractory or recurrent malignant non-testicular germ-cell tumours. The long-term prognosis of patients with poor response or after first relapse was almost similar to those receiving first-line treatment. This strategy merits further investigation.

FUNDING

Deutsche Krebshilfe eV, Bonn, Elterninitiative Kinderkrebsklinik Düsseldorf eV, the Barbara and Hubertus-Trettnerstiftung, and the Marie Quendt Fund.

Sacrococcygeal tumors: clinical characteristics and outcome of pediatric patients treated at South Egypt Cancer Institute. A retrospective analysis

BACKGROUND

Sacrococcygeal tumors (SCT) are relatively uncommon tumors affecting neonates, infants and children. The aim of this article is to clarify any special characterizations in natural history, clinical presentation and outcome of such tumors treated at South Egypt Cancer Institute, the only research center located in South Egypt.

METHODS

A retrospective analysis of children with SCT treated at the Pediatric Oncology department South Egypt Cancer Institute, Assiut University between 2004 and 2010.

RESULTS

Nineteen children were included in the study. Age ranged between 10 days and 5 years. All but three had sacral mass at presentation. AFP levels ranged between normal age-related levels and 217,200 ng/ml. Initial resection was possible in 11, while eight patients with clinical suggestion of advanced malignant disease were inoperable. They received initial chemotherapy followed by delayed surgery. Yolk sac tumor (YST) was reported in 52.9% of patients. Recurrence was reported in 5 patients (3 mature teratomas and 2 YST). Five-year OS and RFS rates of patients who had malignant disease were 81.8% and 77.8% respectively.

CONCLUSIONS

Older age and delay in presentation that resulted in predominance of extensive disease and malignant transformation at presentation were the main challenges we faced in managing patients with SCT in our locality.

Brain metastases during follow-up of children and adolescents with extracranial malignant germ cell tumors: risk adapted management decision tree analysis based on data of the MAHO/MAKEI-registry

BACKGROUND

The overall risk for brain metastases among children and adolescents with extracranial malignant germ cell tumors (mGCT) is low but may vary between subgroups. Early identification of subgroups with an increased risk for brain metastasis is therefore important.

PROCEDURE

We analyzed 900/2,160 patients from the German MAHO/MAKEI registry on children and adolescents with malignant extracranial GCT (pure teratomas (grade 0-3) were not included). For follow-up evaluation, patients with brain metastases at diagnosis and those with a follow-up shorter than 32 months after diagnosis (longest interval to brain metastases in our cohort) were excluded. Patients were censored at detection of brain metastases or death due to other causes. A decision tree analysis considering age, gender, site of primary tumor, and presence of other metastases at diagnosis as risk factors for brain metastases was performed.

RESULTS

Among 838 eligible patients, 9 acquired brain metastases during follow-up, accounting for death in 5. There were no brain metastases in absence of extracranial metastases at diagnosis. If extracranial metastases were detected in absence of mediastinal mGCT the risk for brain metastases was 1.2% (95% CI: 0.2-3.5.%). In contrast, risk was increased to 37.5 (95% CI 15.2-64.6%) in patients with mediastinal GCTs and extracranial metastases.

CONCLUSION

A high-risk subgroup is detected with a decision tree analysis approach. These patients may benefit from an intensified chemotherapy. Close surveillance for CNS-metastases is warranted in this high-risk group while less close monitoring in low-risk patients is justified. Pediatr Blood Cancer 2013;60:217-223. © 2012 Wiley Periodicals, Inc.

Prognosis of malignant sacrococcygeal germ cell tumours according to their natural history and surgical management

INTRODUCTION

Malignant sacrococcygeal (SC) germ cell tumours (GCT) may be diagnosed as primary pelvic tumour or malignant recurrence of foetal SC teratoma (FSCT) operated during the neonatal period. In order to evaluate the difference between these two populations, the authors report their experience with SC-GCT registered in the French TGM 95 protocol.

POPULATION AND METHODS

The protocol comprised risk-adapted-chemotherapy (CT) followed by surgery. Standard risk (SR: localized tumour completely resected) had no adjuvant therapy. Intermediate-Risk (IR: localized tumour, incomplete or no initial surgery with αFP<15,000 ng/ml) received Vinblastine-Bleomycin-Cisplatin regimen; while High-Risk (HR: αFP > 15,000 ng/ml and/or metastases) received Etoposide-Ifosfamide-Cisplatin.

RESULTS

Fifty-seven patients with SC-GCT, aged 0-80 months (median 16), were registered between 1995 and 2005. Nineteen patients had secondary SC-GCT after FSCT. All patients received CT: 17 IR and 1 SR after reevolution; 39 HR (25 with metastases). 51 patients underwent delayed surgery, which was incomplete in 8 patients.

EVOLUTION

Seventy-two percent of the secondary SC-GCT had systematic biological follow-up. αFP increasing was the first presenting sign in 80% of the cases. Patients with secondary SC-GCT had a lower median αFP level at diagnosis, were less frequently classified as HR and received less CT. The two groups with secondary vs. primary SC-GCT had a statistically similar favourable outcome (Overall Survival: 93.8% vs. 86.2%; Event-Free Survival: 89.2 vs. 78.2%; p > 0.34 and >0.32), respectively, but with less burden of therapy.

CONCLUSIONS

SC-GCT has a good overall prognosis provided complete surgery is achieved and CT is administered to IR and HR patients. SC-GCT in patients followed by αFP after treatment for FSCT had less tumour extension than newly-diagnosed patients, probably because of earlier detection of the disease.

Long-term outcomes of surgery for malignant sacrococcygeal teratoma: 20-year experience of a regional UK centre

BACKGROUND

The timing of surgery for malignant sacrococcygeal teratoma is controversial. The long-term outcomes and complications of surgery for this rare tumour are presented.

METHODS

All cases of malignant sacrococcygeal teratoma in the 20-year period 1987-2006 were identified and the case notes retrieved. The age at diagnosis, investigations, presentation, type of surgery, early complications, recurrence rates, long-term complications and outcomes were recorded.

RESULTS

Twelve patients (three males, nine females) were identified. Mean age at presentation was 20.8 months (range: 12-39 months). All had the Carboplatin-Etoposide-Bleomycin chemotherapeutic protocol. The average time of follow-up was 10.6 years (range: 1-17 years). Ten patients had excision of their tumours following chemotherapy, whilst two patients had excision prior to chemotherapy. Two patients had recurrence of their tumours. There was one death (8%), which was due to disseminated metastasis. The other 11 children were all well at the last follow-up.

CONCLUSION

Surgery for malignant sacrococcygeal teratoma is safe and has a low complication rate. The long-term outcomes are favourable with minimal side effects.

Role of prognostic factors in the management of pediatric solid tumors

The importance of prognostic factors in predicting outcome in pediatric oncology is largely recognized, and most current protocols tailor treatment based on risk stratification. Further refinements of classical staging systems are ongoing, and the future of pediatric oncology is in the development of strategies based on individual tumor characteristics. This review details significant advances in our understanding of prognostic factors in the most common pediatric solid tumors and potential applications for clinical management.

Application of the adult international germ cell classification system to pediatric malignant non-seminomatous germ cell tumors: a report from the Children's Oncology Group

BACKGROUND

The purpose of this analysis is to explore whether the International Germ Cell Classification Consensus (IGCCC) tumor marker criteria, developed for adult males with metastatic malignant germ cell tumors (MGCT), are prognostic among pediatric patients and whether tumor marker data may be relevant in pediatric risk stratification.

PROCEDURE

The IGCCC was applied to 436 pediatric germ cell patients treated on Pediatric Intergroup Studies from 1990 to 1996. Multivariable Cox proportional hazards model identified prognostic variables; survival rates among IGCCC risk groups were compared using the log-rank test. Concordance and relative performance of IGCCC versus COG risk stratification was evaluated.

RESULTS

Applying the IGCCC, 21% of pediatric patients were good risk (GR), 35% intermediate risk (IR), and 44% poor risk (PR). Only modest concordance between IGCCC and COG stratification systems was noted (49%). Nonetheless, the IGCCC identified a group of PR patients who had significantly worse event-free survival (EFS) versus GR/IR patients (6-year EFS 80% vs. 91%), which was similar to the difference observed using the COG system (6-year EFS 77% vs. 90%). The IGCCC performed well within subgroups for which the IGCCC is not intended (prepubertal, female, and non-metastatic patients).

CONCLUSIONS

Applying the IGCCC system to pediatric patients produces a different stratification than does the application of the COG system, although both are prognostic. Development of a de novo pediatric prognostic classification is warranted.

Prenatal and Neonatal MRI of Sacrococcygeal Teratoma With Surgical Correlation

We report a case in which a sacrococcygeal teratoma was identified and characterized on prenatal and postnatal MRI, and correlated with subsequent surgical resection.

Metastatic tumors in bone marrow: histopathology and advances in the biology of the tumor cells and bone marrow environment

The nonhematopoietic tumors most often diagnosed in the bone marrow are metastatic. Currently, accurate diagnosis of tumor metastasis requires integration of the clinical findings; morphological features; and results of immunohistochemical stains, cytogenetics, and molecular studies. This review focuses on a practical approach to the diagnosis of metastatic tumors in the bone marrow according to current standards of practice and discusses recent advances in understanding of tumor metastasis and the interaction between tumors and the bone marrow environment.

Malignant cervical teratoma: report of a case in a newborn

Malignant cervical teratoma (MCT) usually appears in newborns as an enlarging mass of the neck that causes respiratory distress, requiring prompt airway control. We report a case of MCT in an infant electively delivered at 32 weeks to prevent airway impairment. At first, the preoperative diagnosis was hygroma of the neck, and a surgical excision was performed when the newborn was 9 days old. Diagnosis was benign extragonadic immature teratoma, but it was changed in MCT when cervical metastases appeared and the alpha-fetoprotein (AFP) level increased. Subsequent surgical procedures and chemotherapy were necessary. The child has been free from disease and healthy for 7 years since the last surgery. The preoperative diagnosis of MCT is difficult because of its rarity and non-specific clinical findings. Surgical excision is required for an adequate cure and airway repair; a long-term follow-up is mandatory to promptly treat any recurrence.

[Sacrococcigeal teratoma: report of three cases]

Germ cell tumors are originated from the primary stem cell located either in or outside the gonadal system. Teratomas are the major group, with the sacrococcygeal location being the most common extragonadal site, independent they are benign or malignant. We describe three cases of sacrococcygeal teratoma and emphasize aspects of diagnosis, surgical techniques and complementary approaches.

Epidemiologic analysis of 1,442 children and adolescents registered in the German germ cell tumor protocols

BACKGROUND

Germ cell tumors (GCTs) constitute a heterogeneous group of tumors that significantly vary with respect to their clinical presentation and biology. The objective of this analysis was to analyze a large population-based pediatric cohort of GCTs and to evaluate the parameters age, sex, site of the tumor, histology, and potential correlations between these parameters.

PROCEDURE

Between 1981 and 2000, 1,442 patients were prospectively enrolled onto the German protocols for testicular and non-testicular GCTs. Tumors were histologically classified according to the WHO.

RESULTS

We observed a bimodal age distribution with a first peak during infancy and a second after the onset of puberty. At birth, almost all tumors were teratomas, sometimes with microfoci of yolk sac tumor, which on the other hand, was the predominant histology during childhood. After the onset of puberty, germinomatous GCTs represented the most frequent histological subtype, and malignant non-germinomatous GCTs often presented as mixed tumors with choriocarcinoma and embryonal carcinoma components. During infancy, non-gonadal GCTs accounted for the majority of GCTs, while after the onset of puberty, gonadal GCTs predominated. Notably, among non-gonadal GCTs, there was a female predominance during childhood and a strong male predominance during adolescence.

CONCLUSIONS

Two separate groups of GCTs with distinct clinical features relevant for differential diagnosis and the diagnostic assessment can be distinguished. This observation correlates with genetic studies that reveal different genetic changes in childhood and adolescence GCTs. Further studies are needed to elucidate the molecular mechanisms of germ cell and GCT development that account for the age- and sex-dependent clinical manifestation.