Secondary glioblastoma after treatment of intracranial germinoma - would radiation-only therapy still be safe? Case report

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.

A patient with heterochronous double primary tumor of basal ganglia germ cell tumors followed by diffuse hemispheric glioma: a case report

BACKGROUND

Basal ganglia germ cell tumor (BGGCT) is a rare central nervous system (CNS) tumor. Diffuse hemispheric gliomas, H3 G34-mutant (DHGs) is an invasive glioma involving the cerebral hemispheres. The diagnosis of DHGs depends on the integration of histopathology and molecular pathology.

CASE REPORT

We reported a patient with an initial diagnosis of BGGCT that was sensitive to subsequent chemoradiotherapy. Unfortunately, a second high-grade glioma was found on magnetic resonance imaging (MRI) six years later. Subsequently, the tumor was completely removed after surgery and the following histopathology plus next generation sequencing (NGS) testing confirmed the diagnosis of DHGs. Interestingly, we found a germline likely pathogenic variant in FANCA. After surgery, the patient received Stupp regimen. The patient had a relapse 13 months after the Stupp regimen and was doing well after surgery.

CONCLUSIONS

This is the first report of a patient with heterochronous double primary tumor of BGGCT followed by DHGs.

Radiotherapy-induced glioblastoma: distinct differences in overall survival, tumor location, pMGMT methylation and primary tumor epidemiology in Hong Kong chinese patients

INTRODUCTION

Radiotherapy-induced glioblastomas (RIGB) are a well-known late and rare complication of brain irradiation. Yet the clinical, radiological and molecular characteristics of these tumors are not well characterized.

METHODS

This was a retrospective multicentre study that analysed adult patients with newly diagnosed glioblastoma over a 10-year period. Patients with RIGB were identified according to Cahan's criteria for radiation-induced tumors. A case-control analysis was performed to compare known prognostic factors for overall survival (OS) with an independent cohort of IDH-1 wildtype de novo glioblastomas treated with standard temozolomide chemoradiotherapy. Survival analysis was performed by Cox proportional hazards regression.

RESULTS

A total of 590 adult patients were diagnosed with glioblastoma. 19 patients (3%) had RIGB. The mean age of patients upon diagnosis was 48 years ± 15. The mean latency duration from radiotherapy to RIGB was 14 years ± 8. The mean total dose was 58Gy ± 10. One-third of patients (37%, 7/19) had nasopharyngeal cancer and a fifth (21%, 4/19) had primary intracranial germinoma. Compared to a cohort of 146 de novo glioblastoma patients, RIGB patients had a shorter median OS of 4.8 months versus 19.2 months (p-value: <.001). Over a third of RIGBs involved the cerebellum (37%, 7/19) and was higher than the control group (4%, 6/146; p-value: <.001). A fifth of RIGBs (21%, 3/19) were pMGMT methylated which was significantly fewer than the control group (49%, 71/146; p-value: .01). For RIGB patients (32%, 6/19) treated with re-irradiation, the one-year survival rate was 67% and only 8% for those without such treatment (p-value: .007).

CONCLUSION

The propensity for RIGBs to develop in the cerebellum and to be pMGMT unmethylated may contribute to their poorer prognosis. When possible re-irradiation may offer a survival benefit. Nasopharyngeal cancer and germinomas accounted for the majority of original malignancies reflecting their prevalence among Southern Chinese.

Clinical, imaging, and molecular features of radiation-induced glioblastomas developing more than 20 years after radiation therapy for intracranial germinomatous germ cell tumor: illustrative cases

BACKGROUND

Germinomatous germ cell tumor is highly sensitive to chemoradiotherapy; patients are expected to survive for decades. Many radiation-induced malignant gliomas (RIMGs) occur >10 years after radiotherapy. Standard therapy for RIMGs has not been established because of the lesion's rarity, the patient's shorter survival period, and the risk of radiation necrosis by repeat radiation.

OBSERVATIONS

Two patients, a 32-year-old man and a 50-year-old man, developed glioblastomas more than 20 years after radiation monotherapy for germinoma with or without mature teratoma. The first patient showed a tumor in the left frontotemporal region with disseminated lesions and died 2 months after partial resection of the tumor without responding to the chemotherapy with temozolomide and bevacizumab. Methylation classifier analysis classified the pathology as closest to diffuse pediatric-type high-grade glioma, Rtk1 subtype. The second patient showed a tumor mass in the brainstem and left cerebellar peduncle, which worsened progressively during chemotherapy with temozolomide and bevacizumab. The tumor transiently responded to stereotactic radiotherapy with the CyberKnife. However, the patient died of RIMG recurrence-related aspiration pneumonia 11 months after the biopsy. Methylation classifier analysis classified the pathology as closest to infratentorial pilocytic astrocytoma.

LESSONS

Chemoradiotherapy may improve the survival of patients with RIMGs. Furthermore, molecular features may influence the clinical, locoregional, and pathological features of RIMG.