Treatment failure in intracranial primary germinomas

Treatment Outcomes and Prognostic Factors of Intracranial Germ Cell Tumors: A Single Institution Retrospective Study

BACKGROUND

This study analyzed the epidemiology and treatment outcomes of germ cell tumor patients at a single institution.

METHODS

A retrospective analysis was conducted on intracranial germ cell tumor (iGCT) patients treated at a single tertiary hospital from 2004 to 2019. Patients were categorized based on treatment modality: Korean Society for Pediatric Neuro-Oncology (KSPNO) protocol or bleomycin, etoposide, and cisplatin with radiation therapy.

RESULTS

Forty-nine iGCT patients treated with combined chemotherapy and radiotherapy were analyzed. The median age was 19 years (range: 6-40), with a median follow-up duration of 148.0 months (range: 10.5-265.5). Tumors were most common in the pineal gland (51.0%). Although no significant differences in outcomes were observed between treatment modalities, outcomes varied significantly by pathological type. The 10-year progression-free survival rates for germinoma and non-germinomatous germ cell tumors (NGGCTs) were 88.1% and 32.7%, respectively (p=0.003), while the 10-year overall survival rates were 92.9% and 67.5%, respectively (p<0.001). Fourteen patients experienced CTCAE (Common Terminology Criteria for Adverse Events) grade ≥3 adverse events, with one event-related death.

CONCLUSION

Pure germinoma demonstrated higher survival and lower recurrence rates compared to NGGCT. The KSPNO protocol appears to be an acceptable and safe treatment option for iGCT patients. Further multi-institutional studies with larger cohorts are warranted.

CNS Germ Cell Tumors: Molecular Advances, Significance in Risk Stratification and Future Directions

Central Nervous System Germ Cell Tumors (CNS GCTs) represent a subtype of intracranial malignant tumors characterized by highly heterogeneous histology. Current diagnostic methods in clinical practice have notable limitations, and treatment strategies struggle to achieve personalized therapy based on patient risk stratification. Advances in molecular genetics, biology, epigenetics, and understanding of the tumor microenvironment suggest the diagnostic potential of associated molecular alterations, aiding risk subgroup identification at diagnosis. Furthermore, they suggest the existence of novel therapeutic approaches targeting chromosomal alterations, mutated genes and altered signaling pathways, methylation changes, microRNAs, and immune checkpoints. Moving forward, further research is imperative to explore the pathogenesis of CNS GCTs and unravel the intricate interactions among various molecular alterations. Additionally, these findings require validation in clinical cohorts to assess their role in the diagnosis, risk stratification, and treatment of patients.

Treatment outcomes of intracranial germinoma: a retrospective analysis of 170 patients from a single institution

PURPOSE

To perform a retrospective analysis of patients with intracranial germinoma treated in our department to evaluate treatment outcomes and determine optimal treatment strategies.

METHODS

We reviewed the treatment outcomes of 170 patients with intracranial germinoma who were treated in our department from January 1996 to January 2017. The median patient age was 15 years old. Among the patients, 56 (33%) were pathologically diagnosed, and 114 (67%) were diagnosed clinically. Various radiation fields and doses were used. Cerebrospinal fluid (CSF) and serum beta-human chorionic gonadotropin (β-HCG) levels were examined before treatment in 114 patients. Endocrinological evaluation was performed in 141 patients before and after treatment. A total of 38 patients received chemotherapy prior to radiotherapy (RT). The median follow-up time was 64.5 months (range 4-260.5 months).

RESULTS

The 5- and 10-year overall survival (OS) rates were 94.5% and 91.3%, respectively. The relapse-free survival (RFS) rates at 5- and 10-years were 91.9% and 78.1%, respectively. Relapses occurred in 18 patients within 6 months-10 years. The spinal cord metastasis rate was 3.4% in patients with a localized lesion who did not receive spinal cord irradiation and 16.7% in patients with bifocal disease who were treated using whole ventricular irradiation (WVI) or whole brain radiotherapy (WBRT). Treatment failure did not occur in patients receiving chemoradiotherapy or in patients receiving three-dimensional conformal radiation therapy (3D-CRT)/intensity-modulated radiation therapy (IMRT). The RFS rate did not have a statistically significant correlation with the CSF/serum β-HCG level. After RT, 19.1% of the patients developed newly impaired pituitary function and required hormone replacement therapy.

CONCLUSIONS

WVI or WBRT+ primary boost (PB) is a sufficient irradiation field for localized intracranial germinoma, while patients with bifocal disease should undergo craniospinal irradiation (CSI), especially when treated with RT alone. CSF β-HCG is not a prognostic marker for intracranial germinomas. The treatment results of chemotherapy followed by reduced-dose RT are comparable to those of RT alone. IMRT is recommended for intracranial germinoma to improve the target volume accuracy and decrease the complications of RT.

Understanding the Treatment Strategies of Intracranial Germ Cell Tumors: Focusing on Radiotherapy

Intracranial germ cell tumors (ICGCT) occur in 2-11% of children with brain tumors between 0-19 years of age. For treatment of germinoma, relatively low radiation doses with or without chemotherapy show excellent 10 year survival rate of 80-100%. Past studies showed that neoadjuvant chemotherapy combined with focal radiotherapy resulted in unacceptably high rates of periventricular tumor recurrence. The use of generous radiation volume which covers the whole ventricular space with later boost treatment to primary site is considered as standard treatment of intracranial germinomas. For non-germinomatous germ cell tumors (NGGCT), 10-year overall survival rate is still much inferior than that of intracranial germinoma despite intensive chemotherapy and high-dose radiotherapy. Craniospinal radiotherapy combined with cisplatin-based chemotherapy provides the best treatment outcome for NGGCT; 60-70% of overall survival rate. There is a debate on the surgical role whether surgery can contribute to improved treatment outcome of NGGCT when added to combined chemoradiotherapy. Because higher dose of radiotherapy is required for treatment of NGGCT than for germinoma, it is tested whether whole ventricular irradiation can replace craniospinal irradiation in intermediate risk group of NGGCT to minimize radiation-related late toxicity in the recent studies. To minimize the treatment-related neural deficit and late sequelae while maintaining long-term survival rate of ICGCT patients, optimized administration of chemotherapy and radiotherapy should be selected. Use of technically upgraded radiotherapy modalities such as intensity-modulated radiotherapy or proton beam therapy is expected to bring an improved neurocognitive outcome with longitudinal assessment of the patients.

Predictors of long-term survival following postoperative radiochemotherapy for pathologically confirmed suprasellar germ cell tumors

The aim of this study was to evaluate the predictors of long-term survival following postoperative therapy for suprasellar germ cell tumors (GCTs). A total of 23 patients with pathologically confirmed suprasellar GCTs were reviewed between April, 1987 and October, 2008. The predictors were identified with a univariate Cox proportional hazards model and the results were used to group patients according to outcome. The overall survival (OS) and progression-free survival (PFS) rates for the good- and poor-prognosis two groups were estimated with Kaplan-Meier analysis, with log-rank tests used to assess differences between the groups. The OS rate for all patients was 82.6% at 5 and 72.9% at 10 years. Lesion size (2-4 vs. >4 cm) and pathological type (pure germinoma vs. mixed GCT) were the only significant predictors of OS (P<0.05). The OS rate for the good-prognosis group was 92.9% at both 5 and 10 years, whereas the corresponding rates for the poor-prognosis group were 66.7 and 40.0%, respectively (P=0.020). The PFS rate for the good-prognosis group was 92.9% at 5 and 85.7% at 10 years, whereas the corresponding PFS rates for the poor-prognosis group were 44.4 and 33.3%, respectively (P=0.007). Lesion size and histology predicted outcome following postoperative therapy for suprasellar GCT. Therefore, pathological diagnosis is recommended whenever possible, as histology may dictate the choice of treatment.

Late recurrence of a pineal germinoma 14 years after radiation and chemotherapy: a case report and review of the literature

BACKGROUND

Intracranial germinomas (IG) are rare and highly curable tumors. The incidence and optimal treatment of recurrences are not well defined.

CASE REPORT

A 34-year-old male was diagnosed with a late recurrence of an IG 14 years after the initial diagnosis and treatment. The diagnosis was complicated by the absence of tumor markers and delayed histological sampling of the lesion. Upon histological confirmation, the patient received 2 cycles of conventional chemotherapy, followed by 2 cycles of highdose chemotherapy and peripheral blood stem cell transplantation. The patient achieved a complete remission on magnetic resonance imaging scan. Consolidating radiation of the involved field was performed after termination of the chemotherapy.

CONCLUSION

Limited information on the optimal management of late relapses of IG call for individualized therapeutic approaches. Platinum-based chemotherapy, followed by high-dose chemotherapy and consolidative radiation, appears to be feasible and effective in this situation.

Treatment strategy for intracranial primary pure germinoma

OBJECT

This prospective randomized clinical study will address the efficacy of radiation (RT)-alone and combined with pre-RT chemotherapy (CTX) treatments and propose the novel standard treatment strategy for intracranial primary pure germinoma.

MATERIALS AND METHODS

Between 2005 and 2008, there were 54 patients diagnosed with intracranial primary pure germinomas in a single institute. Twenty-eight patients were enrolled. The mean age of the patients was 16.2 years (range 6-31 years). There were 19 men and 9 women (men/women ratio = 2.1:1). There were 21 patients with solitary tumors and 7 with multiple tumors. These patients were randomized as RT-only treatment group (11 solitary and 3 multiple tumors) and combined (10 solitary and 4 multiple tumors, neo-adjuvant CTX followed by response-adapted RT) treatment group. The follow-up period for RT only group has a median of 58 months (mean 58.2 months, range 41-82 months), and for combine therapy group, the median was 68.5 months (mean 67.8 months, range 41-88 months). All 14 patients in the RT-only group showed complete response (CR) and no recurrence. Eleven patients in the combined group had CR and three patients had partial response after neo-adjuvant CTX. All patients responded to RT as CR without recurrence. At the time of analysis, all 28 patients were alive without evidence of disease.

CONCLUSION

Neo-adjuvant CTX for localized germinomas seems to be unnecessary as a method to reduce radiation dose in our RT protocol. However, the effective control of multifocal or disseminated germinoma can be achieved by neo-adjuvant CTX followed by response-adapted reduced dose RT.

Prognostic value of OCT4 in primary intracranial germinoma: a single institute analysis of 31 cases

OCT4 expresses variably in primary intracranial germinomas. In this study, we tested our hypothesis that such variation of OCT4 is predictive of outcome in primary intracranial germinomas. Thirty-one histologically identified CNS germinoma patients were enrolled in our study. We collected medical data, immunohistochemically evaluated the OCT4 expression level, and followed up all patients from April 2001 to May 2010. We found that 7 of the 31 patients expressed OCT4 weakly, 11 expressed OCT4 moderately, and 13 expressed OCT4 strongly. No significant correlation between the OCT4 expression level and clinicopathological characteristics was observed. WV-CS combined treatment modality showed a better 5-year progression-free survival (PFS) rate than other treatment modalities and a low expression level of OCT4 showed a significantly better 5-year PFS. In both the WV-CS combined treatment modality and other treatments modality group, patients received a better 5-year PFS and had a lower level of OCT4 expression. As a result, we suggest OCT4 as a probable prognostic marker for intracranial germinoma.

Intracranial germinoma: clinical and MRI findings in 56 patients

INTRODUCTION

Intracranial germinoma is a rare malignant tumor, only constituting 0.5-2.0% of all primary intracranial tumors. It usually occurs in children and young adults, it is highly sensitive to radiotherapy or/and chemotherapy, and is potentially curable without operation. To make correct pre-operative diagnosis and spare surgical intervention, we retrospectively reviewed 56 patients in our hospital, and presented clinical findings and MRI characteristics.

MATERIALS AND METHODS

We reviewed medical records and magnetic resonance imaging (MRI) of 56 patients. Information regarding sex, age at diagnosis, clinical presentation, duration of symptom, and associated neurologic deficits was noted. The tumor location, number of metastasis, size, margin, involved tissues, and characteristics of signal intensity on MRI were analyzed by two experienced radiologists, respectively.

RESULTS

In the series, 57% of intracranial germinoma was located in pineal region, 32% in suprasellar region, and 9% in basal ganglia region. One patient was found germinoma with synchronous lesions in pineal and suprasellar region. Sixty-three percent of patients were male in pineal region, 39% and 100%, respectively, in suprasellar region and basal ganglia region. Age at diagnosis ranged from 3 to 21 years (mean, 12.5 years) with a peak between 10 and 18 years.

CONCLUSIONS

Intracranial germinoma has some features in terms of age, sex, clinical presentation, and MRI. These features are in favor of pre-operative diagnosis and thus make for good prognosis.

Pattern of relapse and outcome of non-metastatic germinoma patients treated with chemotherapy and limited field radiation: the SFOP experience

Over the last two decades, chemotherapy has been introduced in protocols for patients with intracranial germinoma with the objective of reducing the volume and the dose of irradiation without compromising survival rates. The aim of this work is to critically analyze the pattern of relapse in a cohort of patients with nonmetastatic germinoma prospectively treated with chemotherapy followed by focal field radiation. Data of all germinoma patients registered in the French protocol for intracranial germ cell tumors between 1990 and 1999 were reviewed. The pattern of relapse, management, and outcome were analyzed in 10 of 60 patients who developed a recurrence after initial treatment. In 9 patients, the site of recurrence was local or loco-regional, notably in the periventricular area for 8. One patient only had isolated distant leptomeningeal relapse. The review of the sites of relapse suggests that most recurrences could have been avoided with a larger ventricular field of radiation. Treatment at first relapse included chemotherapy (10 patients), high-dose chemotherapy and stem cell transplant (8 patients), and/or radiation therapy (4 patients). Five patients experienced a second relapse. At a median follow-up of 72 months since the first relapse, 8 patients are alive in second or third remission. This review identified an excess of periventricular relapses when the focal field of radiation is used in the combined management of germinoma. These relapses are predominantly marginal or outside radiation fields. Ventricular field radiation appears a logical alternative to decrease the incidence of such relapses. Future trials should aim at better identifying patients who may benefit from local and ventricular radiation, respectively.

Cognitive Sparing during the Administration of Whole Brain Radiotherapy and Prophylactic Cranial Irradiation: Current Concepts and Approaches

Whole brain radiotherapy (WBRT) for the palliation of metastases, or as prophylaxis to prevent intracranial metastases, can be associated with subacute and late decline in memory and other cognitive functions. Moreover, these changes are often increased in both frequency and severity when cranial irradiation is combined with the use of systemic or intrathecal chemotherapy. Approaches to preventing or reducing this toxicity include the use of stereotactic radiosurgery (SRS) instead of WBRT; dose reduction for PCI; exclusion of the limbic circuit, hippocampal formation, and/or neural stem cell regions of the brain during radiotherapy; avoidance of intrathecal and/or systemic chemotherapy during radiotherapy; the use of high-dose, systemic chemotherapy in lieu of WBRT. This review discusses these concepts in detail as well as providing both neuroanatomic and radiobiologic background relevant to these issues.

Optimal treatment strategy for intracranial germ cell tumors: a single institution analysis

OBJECT

This study retrospectively analyzed the long-term outcomes of 108 consecutive patients to establish the classification and optimal treatment strategy for each subgroup of newly diagnosed germ cell tumors (GCTs).

METHODS

A retrospective review of medical records from the authors' department between April 1989 and March 2007 identified 108 patients with newly diagnosed intracranial GCT. The diagnoses were germinoma in 83 patients, and nongerminomatous GCT (NGGCT) in 25 patients.

RESULTS

In patients with germinoma, the 10-year overall and progression-free survival (PFS) rates at a median follow-up period of 99 months were 86 and 74%, respectively. Recurrences developed during a range of 6 to 153 months (median 26 months) after starting the initial therapy. Patients treated only with chemotherapy demonstrated a shorter PFS rate, and patients treated with chemotherapy followed by reduced-dose radiation therapy to the whole ventricle, whole brain, or craniospinal axis showed significantly better PFS than patients treated with only radiation or reduced-dose radiation therapy to the focal field. Nongerminomatous GCTs were divided into good, intermediate, and poor prognosis groups as proposed by the Japanese Pediatric Brain Tumor Study Group. In the good and intermediate prognosis groups, the 10-year overall and PFS rates were 100 and 93%, respectively. In the poor prognosis group, the 3-year overall and PFS rates were 56 and 29%, respectively. All patients with NGGCTs, in whom the lesions on MR imaging disappeared after combination therapies consisting of resection, radiation therapy, and chemotherapy, remained alive.

CONCLUSIONS

Chemotherapy followed by reduced-dose radiation therapy covering the whole ventricle improves the prognosis for patients with germinoma. Combined therapy of radiation therapy, chemotherapy, and radical resection as an initial or salvage treatment achieved excellent tumor control in the intermediate prognosis NGGCT group. The outcomes were still dismal in the poor prognosis NGGCT group, so initial therapy should target complete disappearance of all lesions on MR imaging.

Optimal treatment for intracranial germinoma: can we lower radiation dose without chemotherapy?

PURPOSE

To review the effectiveness of reduced-dose and restricted-volume radiation-only therapy in the treatment of intracranial germinoma and to assess the feasibility of reducing or eliminating the use of chemotherapy.

METHODS AND MATERIALS

Between January 1996 and March 2007, a retrospective analysis was performed that included 38 patients who received either reduced radiation alone (30 Gy for 26 patients) or reduced radiation with chemotherapy (n = 12 patients). All 38 patients received extended focal (including whole-ventricle) irradiation and were followed up until February 2008. Overall survival (OS) and relapse-free survival (RFS) rates were calculated. Variables associated with survival were evaluated by univariate Cox proportional hazards regression.

RESULTS

Median follow-up was 62.4 months (range, 10.1-142.5 months). The total 5-year OS rate was 93.7%. The 5-year OS and RFS rates for patients receiving radiation only were 100% and 96.2%, respectively. The rates for those receiving radiation plus chemotherapy were 83.3 % and 91.7%, respectively (not statistically significant). No predictive factor was significantly associated with the OS or RFS rate. Chemotherapy had no significant effect on survival but was associated with a higher incidence of treatment-related toxicity.

CONCLUSIONS

A further decrease in the radiation dose to 30 Gy with whole-ventricle irradiation is sufficient to treat selected patients with intracranial germinoma. Wide-field irradiation or chemotherapy should be avoided as these methods are unnecessary. Thus, reduction of the radiation dose to 30 Gy may be feasible, even without chemotherapy.

Low-dose craniospinal irradiation as a definitive treatment for intracranial germinoma

PURPOSE

To determine the optimal radiotherapy (RT) dose and volume for treatment of intracranial germinoma.

MATERIALS AND METHODS

Eighty-one intracranial germinoma patients (33 pathologically-verified; 48 presumed by radiosensitivity testing) treated with RT alone between 1971 and 2002 were analyzed. The RT volume varied from focal (13) to whole brain (8), or to the entire neuraxis (60). All the cases after 1982 received craniospinal irradiation (CSI). Radiation dose was reduced gradually during the study period from 59 to 39.3 Gy for primary tumors, and from 34.2 to 19.5 Gy for the neuraxis. The median follow-up time was 120 months (48-260 months).

RESULTS

Five- and ten-year relapse-free survival rates were 98.8% and 94.1%, respectively. All the recurrences occurred in the patients who received local (4/13) or whole brain RT (1/8). None of the patients who received CSI suffered from a recurrence. Forty-six patients received 45 Gy or less to the primary site and 22 patients received less than 20 Gy to the spinal axis.

CONCLUSION

Low-dose CSI-based RT should remain the standard treatment for intracranial germinoma. The RT dose can be reduced to 39.3 Gy for primary tumor sites and to 19.5 Gy for the spinal axis.

Extended focal radiotherapy of 30 Gy alone for intracranial synchronous bifocal germinoma: a single institute experience

OBJECTS

To evaluate the disease characteristics and treatment outcomes for patients with intracranial synchronous bifocal germinomas treated with extended focal irradiation alone.

METHODS

Between January 1996 and March 2007, seven patients (three males and four females) with intracranial synchronous bifocal germinomas treated at Taipei Veterans General Hospital were reviewed. The median age at diagnosis was 14 years (range, 11-28 years). Four patients had surgery before radiotherapy. All patients underwent extended focal irradiation encompassing the whole ventricle system with a total radiation dose of 30 Gy (2 Gy daily). No patient received scheduled systemic chemotherapy before or after radiotherapy. Disease characteristics, treatment outcomes, and the impact of lesion numbers (single vs. bifocal) on survivals were investigated.

RESULTS

With a median follow-up time of 49 months (range, 20-66 months), the 2- and 5-year survival rates were both 100%. After treatment, all patients had good performance without recurrence. No severe complication was observed. In comparison, the overall survival (OS, p = 0.475) and the disease-free survival (DFS, p = 0.537) rates were not significantly different between bifocal- and single-lesion groups. Lesion numbers did not affect both OS and DFS. In addition, the incidence of neuraxial seeding was not higher in patients with bifocal germinomas as compared to those with single lesion.

CONCLUSIONS

Intracranial germinomas are extremely radiosensitive. Young patients with synchronous bifocal germinomas could be successfully treated with extended focal 30-Gy radiotherapy alone. The therapeutic advantage using this regimen needs to be further evaluated with larger sample size and longer follow-up time.

Mixed germ cell tumors in septum pellucidum after radiochemotherapy of suprasellar germinoma: de novo metachronous or recurrent neoplasms?

INTRODUCTION

Mixed germ cell tumors (GCTs) consisting of a germinoma and a mature teratoma in the septum pellucidum have never been described previously; the patient we present here is the first reported example.

CASE REPORT

This case involves an 18-year-old man who presented with abnormal behavior, impairment in recent memory, and emotional change. Five years ago, he received five cycles of chemotherapy using cisplatin and ectoposide and 24G of local radiotherapy for clinical diagnosis of suprasellar germinoma in another hospital. The tumor was then completely resolute. Magnetic resonance imaging in our hospital revealed a large fatty mass located primarily in the septum pellucidum and some portions of the corpus callosum; a heterogeneous enhancing tumor was observed in the surrounding area. The second tumor was completely removed. The histological diagnosis was mixed GCTs containing the component of a germinoma and a mature teratoma.

CONCLUSION

This case is characterized by a second GCT occurring at a different site and with a different histological type, long after complete resolution of suprasellar germinoma. Although it is very difficult to draw conclusions about the correlation between the first and second GCTs, neurosurgeons should always pay attention to the pathological variety and dynamic pathological changes in GCTs once they start to examine and treat them.

Late recurrence and salvage therapy of CNS germinomas

Central nervous system (CNS) germinoma is a curable tumor and its recurrence rate after initial therapy may be approximately 10% or higher. This study elucidates the time-course of recurrence and results of salvage therapy. Twenty-five patients with recurrent germinoma treated at Hokkaido University Hospital were retrospectively reviewed. The median age at initial treatment was 12 years (range: 8-37). All patients had been tumor-free for at least 6 months after the initial treatment. The median follow-up period was 134 months (range: 44-338). The median age at first recurrence was 18 years and the median time to the first recurrence was 50 months. Among the patients, 9 (36%) had the first recurrence at 60 months or later. The latest recurrence in a patient occurred 230 months after the initial treatment. The results of salvage therapy were estimated in all 25 patients. Seventeen patients (68%) were salvaged and were tumor-free at the final observation. The remaining 8 patients died of disease. At first recurrence, 11 patients were treated using radiation therapy with or without surgery and 7 out of the 11 patients died due to the recurrent tumor. On the other hand, 13 patients who received salvage chemotherapy and radiotherapy were tumor-free at the last follow-up. In conclusion, late recurrence is not a rare event in patients with CNS germinoma. To identify a true cure rate of this disease, a 10-year or longer observation period may be required. As a salvage therapy, platinum-based chemotherapy followed by wide-field low-dose radiation therapy appears to be effective.