Levels of beta-human chorionic gonadotropin in cerebrospinal fluid of patients with malignant germ cell tumor can be used to detect early recurrence and monitor the response to treatment

Clinical characteristics and predictive factors of delayed diagnosis in patients with sellar germ cell tumors

PURPOSE

To investigate the clinical characteristics and predictive factors associated with delayed diagnosis in patients with sellar germ cell tumors (GCTs), aiming for early diagnosis.

METHODS

A total of 345 patients with sellar GCTs were retrospectively collected. Patients were classified into a delayed diagnosis group (> 6 months from onset to diagnosis) and a non-delayed diagnosis group (≤ 6 months). We compared general characteristics, clinical symptoms, diagnostic methods, treatment strategies, tumor prognosis, and pituitary function between the two groups. Predictive factors for delayed diagnosis were explored using multivariate logistic regression analysis.

RESULTS

225 patients (65.2%) experienced delayed diagnosis. Although there was no association between delayed diagnosis and survival rates or tumor recurrence rates, the delayed diagnosis group had a higher incidence of central diabetes insipidus, central adrenal insufficiency, central hypothyroidism, central hypogonadism, and growth hormone deficiency. Moreover, polyuria/polydipsia (OR 5.46; 95% CI 2.33-12.81), slow growth (OR 5.86; 95% CI 2.61-13.14), amenorrhea (OR 6.82; 95% CI 2.68-17.37), and germinoma (OR 4.99; 95% CI 1.08-3.61) were associated with a higher risk of delayed diagnosis, while older age of onset (OR 0.88; 95% CI 0.84-0.94) and nausea/vomiting (OR 0.31; 95% CI 0.15-0.63) contributed to earlier diagnosis.

CONCLUSION

In patients with sellar GCTs, delayed diagnosis is common and linked to increased pituitary dysfunction. The initial symptoms of slow growth, polyuria/polydipsia, and amenorrhea, as well as germinoma with negative tumor markers, predict the possibility of a delayed diagnosis. Early diagnosis is crucial to minimize the impact of sellar GCTs on pituitary function.

Plasma miRNA expression profile in pediatric pineal pure germinomas

Background

Pure germinomas account for 40% of pineal tumors and are characterized by the lack of appreciable tumor markers, thus requiring a tumor biopsy for diagnosis. MicroRNAs (miRNA) have emerged as potential non-invasive biomarkers for germ cell tumors and may facilitate the non-invasive diagnosis of pure pineal germinomas.

Material and methods

A retrospective chart review was performed on all patients treated at the Children's Cancer Hospital Egypt diagnosed with a pineal region tumor between June 2013 and March 2021 for whom a research blood sample was available. Plasma samples were profiled for miRNA expression, and DESeq2 was used to compare between pure germinoma and other tumor types. Differentially expressed miRNAs were identified. The area under the curve of the receive;r operating characteristic curve was constructed to evaluate diagnostic performance.

Results

Samples from 39 pediatric patients were available consisting of 12 pure germinomas and 27 pineal region tumors of other pathologies, including pineal origin tumors [n = 17; pineoblastoma (n = 13) and pineal parenchymal tumors of intermediate differentiation (n = 4)] and others [n = 10; low-grade glioma (n = 6) and atypical teratoid rhabdoid tumor (n = 4)]. Using an adjusted p-value <0.05, three miRNAs showed differential expression (miR-143-3p, miR-320c, miR-320d; adjusted p = 0.0058, p = 0.0478, and p = 0.0366, respectively) and good discriminatory power between the two groups (AUC 90.7%, p < 0.001) with a sensitivity of 25% and a specificity of 100%.

Conclusion

Our results suggest that a three-plasma miRNA signature has the potential to non-invasively identify pineal body pure germinomas which may allow selected patients to avoid the potential surgical complications.

Pineal/germ cell tumors and pineal parenchymal tumors

INTRODUCTION

Pineal region tumors (PRTs) are tumors arising from the pineal gland and the paraspinal structures. These tumors are rare and heterogeneous that account for 2.8-10.1% and 0.6-3.2% of tumors in children and in all ages, respectively. Almost all types and subtypes of CNS tumors may be diagnosed in this region. These tumors come from cells of the pineal gland (pinealocytes and neuroglial cells), ectopic primordial germ cells (PGC), and cells from adjacent structures. Hence, PRTs are consisted of pineal parenchyma tumors (PPTs), germ cell tumors (GCTs), neuroepithelial tumors (NETs), other miscellaneous types of tumors, cystic tumors (epidermoid, dermoid), and pineal cyst in addition. The symptoms of PRTs correlate to the increased intracranial cranial pressure due to obstructive hydrocephalus and dorsal midbrain compression. The diagnostic imaging studies are mainly MRI of brain (with and without gadolinium) along with a sagittal view of whole spine. Serum and/or CSF AFP/β-HCG helps to identify GCTs. The treatment of PRTs is consisted of the selection of surgical biopsy/resection, handling of hydrocephalus, neoadjuvant and/or adjuvant therapy according to age, tumor location, histopathological/molecular classification, grading of tumors, staging, and threshold value of markers (for GCTs) in addition.

METHODS

In this article, we review the following focus points: 1. Background of pineal region tumors. 2. Pineal GCTs and evolution of management. 3. Molecular study for GCTs and pineal parenchymal tumors. 4. Review of surgical approaches to the pineal region. 5. Contribution of endoscopy. 6. Adjuvant therapy (chemotherapy, radiotherapy, and combination). 7.

FUTURE DIRECTION

RESULTS

In all ages, the leading three types of PRTs in western countries were PPTs (22.7-34.8%), GCTs (27.3-34.4%), and NETs (17.2-28%). In children and young adults, the leading PRTs were invariably in the order of GCTs (40-80.5%), PPTs (7.6-21.6%), NETs (2.4-37.5%). Surgical biopsy/resection of PRTs is important for precision diagnosis and therapy. Safe resection with acceptable low mortality and morbidity was achieved after 1970s because of the advancement of surgical approaches, CSF shunt and valve system, microscopic and endoscopic surgery. Following histopathological diagnosis and classification of types and subtypes of PRTs, in PPTs, through molecular profiling, four molecular groups of pineoblastoma (PB) and their oncogenic driver were identified. Hence, molecular stratified precision therapy can be achieved.

CONCLUSION

Modern endoscopic and microsurgical approaches help to achieve precise histopathological diagnosis and molecular classification of different types and subtypes of pineal region tumors for risk-stratified optimal, effective, and protective therapy. In the future, molecular analysis of biospecimen (CSF and blood) along with AI radiomics on tumor imaging integrating clinical and bioinformation may help for personalized and risk-stratified management of patients with pineal region tumors.

Clinical significance and pitfalls of human chorionic gonadotropin-related tumor markers for intracranial germinomas

PURPOSE

Measuring serum and cerebrospinal fluid human chorionic gonadotropin (hCG) is essential for the diagnosis of intracranial germ cell tumors. There are three types of hCG-related markers in clinical use: hCGβ, intact hCG, and total hCG. The best marker for the diagnosis of intracranial germ cell tumors, especially germinoma, is currently unknown. This study aimed to evaluate the usefulness of these hCG-related markers.

METHODS

We investigated 19 serum samples obtained from 6 patients with histologically diagnosed germinoma treated in our institute. Serum hCGβ, intact hCG, and total hCG values were measured before, during, and after treatment. Samples with hCG values above the lower limits were considered positive.

RESULTS

The positivity rates of serum hCGβ, intact hCG, and total hCG were 6% (1/17), 47% (7/15), and 42% (8/19), respectively, with the latter two having significantly higher positivity rates than hCGβ (p = 0.041). Both intact and total hCGs showed similar values. The median values of hCGβ, intact hCG, and total hCG before treatment were 0.1 ng/mL, 4.6 mIU/mL, and 4.5 mIU/mL, respectively.

CONCLUSION

Serum intact and total hCGs have higher detection rates than hCGβ in patients with germinoma using available commercial measurement tools.

From Uterus to Brain: An Update on Epidemiology, Clinical Features, and Treatment of Brain Metastases From Gestational Trophoblastic Neoplasia

In this review, we provide the state of the art about brain metastases (BMs) from gestational trophoblastic neoplasia (GTN), a rare condition. Data concerning the epidemiology, clinical presentation, innovations in therapeutic modalities, and outcomes of GTN BMs are comprehensively presented with particular attention to the role of radiotherapy, neurosurgery, and the most recent chemotherapy regimens. Good response rates have been achieved thanks to multi-agent chemotherapy, but brain involvement by GTNs entails significant risks for patients’ health since sudden and extensive intracranial hemorrhages are possible. Moreover, despite the evolution of treatment protocols, a small proportion of these patients ultimately develops a resistant disease. To tackle this unmet clinical need, immunotherapy has been recently proposed. The role of this novel option for this subset of patients as well as the achieved results so far are also discussed.

[Clinical analysis of 30 cases of basal ganglia germinoma in children]

OBJECTIVE

To summarize and analyze the clinical characteristics of children with basal ganglia germinoma and to improve the level of early clinical diagnosis.

METHODS

The clinical data of children diagnosed with basal ganglia germinoma admitted to the Pediatric Surgery Ward of Peking University First Hospital from January 2013 to December 2020 were retrospectively analyzed, and descriptive statistics were used to analyze the clinical characteristics of children with basal ganglia germinoma.

RESULTS

A total of 30 patients were included in the study, 28 were male, 2 were female, the mean age at onset was (9.7±2.2) years, the median disease duration was 7 months, 27 had unilateral disease, and 3 had bilateral disease. The clinical manifestations were decreased limb muscle strength, cognitive function disorders, polydipsia, precocious puberty, intracranial hypertension, dysphonia and swallowing dysfunction. The serum and cerebrospinal fluid tumor marker alpha-fetoprotein (AFP) were normal in the 30 patients, and the serum and cerebrospinal fluid tumor marker β-human chorionic gonadotropin (β-HCG) were normal in 8 patients.The serum β-HCG was normal in 11 patients but the cerebrospinal fluid β-HCG was slightly elevated, and the serum and cerebrospinal fluid β-HCG were slightly elevated in 11 patients. A total of 33 lesions with irregular shapes were found by imaging examination, including 15 (45.5%) patchy lesions, 10 (30.3%) patchy lesions, and 8 (24.2%) round-like high-density lesions. Tumors showed obvious high-density shadows on computed tomography (CT) scan. Magnetic resonance imaging (MRI) scan of the tumors showed low or isointensity on T1WI and isointensity on T2WI, accompanied by mild peritumoral edema, hemispheric atrophy, cerebral peduncle atrophy, calcification, cystic degeneration, ventricular dilatation and wallerian degeneration. On contrast-enhanced scans, the tumor showed no enhancement or heterogeneous enhancement.

CONCLUSION

The main age of onset of germ cell tumors in the basal ganglia in children is about 10 years old, and males are absolutely dominant. The clinical features and imaging manifestations have certain characteristics. With both combined, the early diagnosis of germ cell tumors in the basal ganglia can be improved.

Pituitary Stalk Thickening: Causes and Consequences. The Children's Memorial Health Institute Experience and Literature Review

BACKGROUND

Pituitary stalk thickening (PST) is a rare abnormality in the pediatric population. Its etiology is heterogeneous. The aim of the study was to identify important clinical, radiological and endocrinological manifestations of patients with PST and follow the course of the disease.

MATERIALS AND METHODS

It is a study conducted in 23 patients (13 boys) with PST with/without central diabetes insipidus (CDI) diagnosed between 1990 and 2020 at Children's Memorial Health Institute (CMHI) in Warsaw, Poland. We analyzed demographic data, clinical signs and symptoms, radiological findings, tumor markers, hormonal results, treatment protocols and outcomes.

RESULTS

The median age at the diagnosis of PST was 9.68 years (IQR: 7.21-12.33). The median time from the onset of the symptoms to the diagnosis was 2.17 years (IQR: 1.12-3.54). The most common initially reported manifestations were polydipsia, polyuria and nocturia (82.6%); most of the patients (56.5%) also presented decreased growth velocity. Hormonal evaluation at the onset of PST revealed: CDI (91.3%), growth hormone deficiency (GHD) (56.5%), hyperprolactinemia (39%), central hypothyroidism (34.8%), adrenal insufficiency (9%), precocious puberty (8.7%). The majority of the patients were diagnosed with germinoma (seventeen patients - 73.9%, one of them with teratoma and germinoma). Langerhans cell histiocytosis (LCH) was identified in three patients (multisystem LCH in two patients, and unifocal LCH in one patient). A single case of atypical teratoid rhabdoid tumor, suspected low-grade glioma (LGG) and lymphocytic infundibuloneurohypophysitis (LINH). The overall survival rate during the observational period was 87.0%.

CONCLUSIONS

The pituitary infundibulum presents a diagnostic imaging challenge because of its small size and protean spectrum of disease processes. Germinoma should be suspected in all children with PST, especially with CDI, even when neurological and ophthalmological symptoms are absent.

Placental alkaline phosphatase levels in cerebrospinal fluid can have a decisive role in the differential diagnosis of intracranial germ cell tumors

OBJECTIVE

Placental alkaline phosphatase (PLAP) in CSF can provide a very high diagnostic value in cases of intracranial germ cell tumors (GCTs), especially in pure germinomas, to the level of not requiring histological confirmation. Unlike other tumor markers, reliable data analysis with respect to the diagnostic value of PLAP serum or CSF levels has not been available until now. This is the first systematic and comprehensive study examining the diagnostic value of CSF PLAP in patients with intracranial GCTs.

METHODS

From 2004 to 2014, 74 patients (average age 19.6 ± 10.6 years) with intracranial GCTs were evaluated using PLAP from their CSF and histological samples. Chemiluminescent enzyme immunoassay was utilized to measure CSF PLAP in the following tumor sites: pineal (n = 32), pituitary stalk, suprasellar (n = 16), basal ganglia (n = 15), intraventricular (n = 9), and cerebellar (n = 5) regions. In addition to classifying GCT cases, all patients underwent tumor biopsy for correlation with tumor marker data.

RESULTS

PLAP in combination with other tumor markers resulted in extremely high sensitivity and specificity of the diagnostic value of intracranial GCTs. Intracranial GCT cases were classified into 1) germinomas, both "pure" and syncytiotrophoblastic giant cell types (n = 38); 2) nongerminomatous GCTs, choriocarcinomas (n = 9) and teratomas (n = 4); and 3) nongerminomas, other kinds of tumors (n = 23). Consequently, all patients received chemoradiation therapy based on elevation of PLAP and the histopathological results. It was also speculated that the level of PLAP could show the amount of intracranial germ cell components of a GCT. PLAP was 100% upregulated in all intracranial germinoma cases. The absence of CSF PLAP proved that the tumor was not a germinoma.

CONCLUSIONS

The current study is the first systematic and comprehensive examination of the diagnostic value of the tumor marker PLAP in pediatric patients with intracranial GCT. Using the level of PLAP in CSF, we were able to detect the instances of intracranial germinoma with very high reliability, equivalent to a pathological diagnosis.

Central Nervous System Germ Cell Tumors: A Review of the Literature

Central nervous system germ cell tumors are rare intracranial tumors that mainly occur in pediatrics with substantial variation in the incidence among different regions and genders. Histologically, central nervous system germ cell tumors can be divided into germinomas and nongerminomatous germ cell tumors. The molecular pathology of central nervous system germ cell tumors, particularly germinomas, is mainly based on the presence of isochromosome 12p, gain-of-function of the KIT gene, and a globally low DNA methylation profile. Diagnoses and differential diagnoses are conducted through imaging, tumor marker detection, surgical biopsy, and cerebrospinal fluid cytology. Germinomas are often treated via whole-ventricular radiotherapy or neoadjuvant chemotherapy combined with reduced-dose whole-ventricular radiotherapy, whereas nongerminomatous germ cell tumors are mainly treated with chemotherapy, surgical resection, and radiotherapy (individually or in combination), depending on tumor composition. Because the main population of patients is pediatric, extending overall survival and reducing treatment side effects should be the main goals of future studies.

Method Validation of Human Chorionic Gonadotropin and α-Fetoprotein in Cerebrospinal Fluid: Aiding the Diagnosis of Intracranial Germ Cell Tumors

BACKGROUND

Our study objective was to validate 2 individual methods to measure α-fetoprotein (AFP) and human chorionic gonadotropin (hCG) in cerebrospinal fluid (CSF) on the Roche cobas® 6000 analyzer. A 3-year retrospective chart review of CSF samples analyzed for AFP and hCG was also conducted.

METHODS

Serum samples with high concentrations of AFP or hCG were added to aliquots of pooled CSF. Precision, linearity, detection limit, recovery, carryover, stability, and interference studies of the AFP and hCG+β assays were performed.

RESULTS

Within-day and day-to-day assay imprecision for AFP and hCG assays were <5% at all concentrations tested. The linear range of the AFP assay was established as 1.0-1100 μg/L, and limit of quantification (LOQ) was <1.0 μg/L. The linear range of the hCG assay was established as 1.0-9500 IU/L and LOQ 0.7 IU/L. There was no demonstrable matrix effect, and neither assay was affected by the presence of hemolysis or xanthochromia. AFP in CSF was stable at room and refrigerated temperatures for up to 48 h at concentrations of 19 and 306 μg/L but increased by 24 h at a concentration of 908 μg/L. AFP in CSF was stable frozen (-20 °C) for up to 7 days. hCG in CSF at all concentrations tested was stable at room, refrigerated, and frozen temperatures for up to 7 days.

CONCLUSIONS

The Roche cobas 6000 AFP and hCG+β assays accurately quantify AFP and hCG in CSF, facilitating rapid and accurate diagnosis as well as monitoring of intracranial germ cell tumors.

Early imaging findings in germ cell tumors arising from the basal ganglia

BACKGROUND

It is difficult to diagnosis early stage germ cell tumors originating in the basal ganglia, but early recognition is important for better outcome.

OBJECTIVE

To evaluate serial MR images of basal ganglia germ cell tumors, with emphasis on the features of early stage tumors.

MATERIALS AND METHODS

We retrospectively reviewed serial MR images of 15 tumors in 14 children and young adults. We categorized MR images of the tumors as follows: type I, ill-defined patchy lesions (<3 cm) without cyst; type II, small mass lesions (<3 cm) with cyst; and type III, large lesions (≥3 cm) with cyst. We also assessed temporal changes of the MR images.

RESULTS

On the initial images, 8 of 11 (73%) type I tumors progressed to types II or III, and 3 of 4 (75%) type II tumors progressed to type III. The remaining 4 tumors did not change in type. All type II tumors (5/5, 100%) that changed from type I had a few tiny cysts. Intratumoral hemorrhage was observed even in the type I tumor. Ipsilateral hemiatrophy was observed in most of the tumors (13/15, 87%) on initial MR images. As tumors grew, cystic changes, intratumoral hemorrhage, and ipsilateral hemiatrophy became more apparent.

CONCLUSION

Early stage basal ganglia germ cell tumors appear as ill-defined small patchy hyperintense lesions without cysts on T2-weighted images, are frequently associated with ipsilateral hemiatrophy, and sometimes show microhemorrhage. Tumors develop tiny cysts at a relatively early stage.

Diagnostic utility and correlation of tumor markers in the serum and cerebrospinal fluid of children with intracranial germ cell tumors

PURPOSE

In order to predict whether tumor markers assist in the histopathologic diagnosis of germ cell tumors (GCTs), we analyzed the correlation of beta human chorionic gonadotropin (βhCG) and alpha-fetoprotein (AFP) in serum and cerebrospinal fluid (CSF) samples at baseline and subsequent follow-up examinations.

METHOD

A retrospective study of patients diagnosed with intracranial GCTs between July 1985 and February 2011 at our institution was conducted to review clinical, surgical, radiological, laboratory, and histopathologic data.

RESULTS

Of the 67 patients eligible for the study, 42 had germinomas and 25 non-germinomatous GCTs. At baseline, serum and CSF AFP agreed in 97.9 % of patients (Cohen's Kappa 0.93). Baseline βhCG samples agreed in only 72.5 % of patients (Cohen's Kappa 0.46). In most cases, values were higher in serum for AFP and in CSF for βhCG. ROC curves estimated from logistic regression model indicated that CSF and serum samples had almost equal diagnostic utility, and the DeLong test showed that the difference in area under curves was not statistically significant. During follow-up (185 paired CSF and serum values from 43 patients), 90.3 % of AFP values correlated between CSF and serum (Cohen's Kappa 0.22, showing fair agreement). For βhCG, 96.2 % of values agreed in serum and CSF (Cohen's Kappa 0.61).

CONCLUSIONS

In some patients, intracranial GCTs can be diagnosed based solely upon positive serum AFP values. In addition, marker values from serum only may be sufficient to predict tumor relapse at interval follow-up examinations.

Pituitary choriocarcinoma in an adolescent male: tumor-derived CG and GH delay diagnosis

BACKGROUND

Primary intracranial germ cell tumors usually present in the first two decades of life, often with precocious puberty. The most common location is in the pineal gland; suprasellar germ cell tumors are rare. We present an additional case of a suprasellar choriocarcinoma producing GH, and review the literature.

CASE

This French Canadian, 17 year-old male presented to the ER with a history of mild weight loss and an episode of syncope while hiking in Mexico, but with no other neurological symptoms. Puberty began at age 13 years (growth spurt: 15-16 years), and he attained an adult height within genetic target by age 16 years. Past medical history was negative except for myopia diagnosed during childhood. System review revealed increased thirst and nocturia. The mother was treated for an oligo-astrocytoma in 2007. Clinical examination showed a euthyroid, well-looking young man with 20 ml testicles. Endocrine evaluation revealed elevated testosterone, mildly elevated PRL, borderline low FT4, and decreased IGF-I, morning cortisol and urine osmolality; tumor markers were positive in serum and CSF (hCG>50 IU/L, AFP>10 ng/mL). A transphenoidal biopsy of a 4.5 cm, homogeneous, non-calcified, suprasellar mass was compatible with the diagnosis of choriocarcinoma and stained intensely for hCG and hGH, presumably the placental variant (GH-V) as previously found in vitro in choriocarcinoma cell lines. Combined chemotherapy and irradiation led to tumor regression and undetectable serum hCG to 36 months of follow-up. He is doing well with no evidence of tumor progression and is on complete hormone replacement therapy.

CONCLUSIONS

Choriocarcinomas can have a hormonal profile that delays the development of symptoms, due to hCG stimulation of both the gonadal and thyroid axes. This report corroborates previous in vitro evidence that choriocarcinoma cells are able to make GH-V. To what extent the patient's tumor-derived GH contributed to his normal growth is not known. Prognosis for this intracranial neoplasm is very reserved, although combined radiotherapy and chemotherapy has been successful in our patient now 36 months post-diagnosis.

Re-evaluation of the significance of cerebrospinal fluid human chorionic gonadotropin in detecting intracranial ectopic germinomas

This study was conducted to establish a reference value for cerebrospinal fluid (CSF) human chorionic gonadotropin (hCG) levels. We also evaluated the sensitivity of CSF hCG as a biomarker to detect intracranial ectopic germinomas that arise in rare sites other than the pineal and suprasellar regions. CSF hCG was measured in 201 male patients who had various types of neurological disease (not tumours of germ cell origin or other malignant tumours). A reference value of 1.009 U/L was established, and the CSF hCG level among different age groups was not significantly different. CSF and serum hCG were measured before and after radiotherapy in 14 consecutive patients with intracranial ectopic germinomas. The CSF hCG levels were all above 1.009 U/L before radiotherapy. In male patients, a CSF hCG value above 1.009 U/L suggests abnormal intrathecal hCG secretion. These results demonstrate that the CSF hCG assay is a sensitive method for diagnosing intracranial ectopic germinoma.

Central nervous system germ cell tumors: classification, clinical features, and treatment with a historical overview

Central nervous system germ cell tumors are neoplasms that affect children and young adults. They are subclassified into germinoma and nongerminomatous germ cell tumors. The latter include teratoma (mature teratoma, immature teratoma, teratoma with malignant transformation), choriocarcinoma, embryonal carcinoma, yolk sac tumors, and mixtures of these entities. Germinoma with syncytiotrophoblastic giant cells is a variant of germinoma. Germinomas respond well to radiation therapy, but late sequelae due to irradiation have been reported. The results of radiation treatment alone for nongerminomatous germ cell tumor are not satisfactory. Combination radiochemotherapy has been applied, and this yields a good outcome with less toxicity for germinomas and better survival of nongerminomatous germ cell tumors. This article also discusses other issues, including the controversy regarding spinal irradiation and the treatment of recurrent disease.

Is biopsy needed to guide management for all patients with presumed intracranial ectopic germinomas

Intracranial germinomas may arise in sites besides pineal and suprasellar regions, which we call intracranial ectopic germinomas (IEGs). In this article we evaluated the rationality of radiotherapy in IEGs when histopathological evidence could not be obtained. Criteria for initiating experimental radiotherapy in patients with clinically presumed IEGs was established according to the reports published in this field and the experience gained from our five histopathologically verified IEG patients. When patients suspected to have IEGs met the criteria, radiotherapy following standard protocol was performed. Strict criteria was also employed to evaluate the effectiveness of radiotherapy after completion of initial experimental dose of radiation and to determine whether total dose of radiation should be delivered. Seven patients clinically suspected to have IEGs met the criteria for radiotherapy. Radiotherapy was evaluated as effective in six patients immediately after completion of initial experimental dose of radiation and the remaining dose was delivered. However, effectiveness of initial experimental radiotherapy was not testified until 2 months later in the other one patient. Total dose of radiation was completed and satisfactory results achieved in all seven patients. In conclusion, the histopathological verification is not mandatory for radiotherapy in patients with IEGs when histopathological evidence can not be obtained. Strict criteria should be followed to enroll patients to undergo experimental radiotherapy.

Current advances in the diagnosis and management of intracranial germ cell tumors

Central nervous system (CNS) germ cell tumors (GCT) account for less than 5% of primary brain tumors in children and young adults, but they continue to attract much attention. Over the past decade, two advances have led to re-evaluation of what constitutes conventional therapy for CNS GCT. For pure germinomas, the challenge remains the determination of the optimal field and dose of irradiation and whether or not the use of chemotherapy can lead to a reduced dose or elimination of irradiation altogether without compromising disease control or survival. For non-germinomatous germ cell tumors, an improvement in the current dismal prognosis is imperative.

Germinoma with syncytiotrophoblastic giant cells recurring 13 years after radiotherapy for a pineal germinoma--case report

A 28-year-old man presented with progressive mental deterioration. Thirteen years earlier he had undergone radiation therapy for a pineal germinoma. Neuroimaging showed a homogeneously enhanced mass lesion along the ventricular wall. The cerebrospinal fluid (CSF) level of human chorionic gonadotropin (HCG) was high. Endoscopic biopsy revealed that the tumor was a two-cell pattern germinoma. The diagnosis was germinoma with syncytiotrophoblastic giant cells (STGC). He first received three cycles of chemotherapy with carboplatin and etoposide and then two cycles with ifosfamide, cisplatin, and etoposide. Subsequently, the tumor size decreased markedly and the CSF level of HCG returned to normal. However, he died 22 months after the recurrence. Histological verification and measurement of tumor markers are necessary for the optimum treatment of germ cell tumors. Adequate initial chemotherapy and long-term follow up are essential for patients with germinoma with STGC.