Adult primitive neuroectodermal tumors: the prognostic value of supratentorial location

Salvage Radiosurgery for Recurrent Supratentorial Primitive Neuroectodermal Tumors: A Single Institutional Series and Review of the Literature

INTRODUCTION

Supratentorial primitive neuroectodermal tumor is a rare, aggressive intrinsic brain tumor with limited treatment options for recurrent disease. SRS as a treatment modality in the recurrent setting was investigated.

METHODS

A retrospective review of 8 patients treated with SRS for local or distant recurrence of supratentorial PNET from 1999 to 2014 was conducted.

RESULTS

Thirty-six tumors were treated in 15 sessions in 8 patients. The median patient age was 22.5 (interquartile range [IQR], 14.75-43.5 years) with a median 21-month period from diagnosis until SRS (IQR, 16-23.75 months). The median prescription isodose volume was 1.85 cm3 (IQR, 1.85-7.02 cm3); median tumor margin dose was 18 Gy (IQR 14-20 Gy); and median isocenters was 2 (range 1-13). No patients experienced adverse radiation effects. All but 1 patient died, and the median overall survival was 32 months (IQR, 26.75-53.5 months) with median overall survival following SRS of 9.5 months (IQR, 5.25-30 months). Univariate analysis failed to demonstrate a statistically significant association between age, number of gamma knife treatments, interval to gamma knife, and margin radiation dose with overall survival.

DISCUSSION/CONCLUSION

This series supports the use of SRS in patients with recurrent supratentorial PNET following multimodal therapy.

Hemorrhagic Suprasellar Central Nervous System Embryonal Tumor in an Adult: Uncommon Features of an Extremely Rare Neoplasm

BACKGROUND

 Occurrences of suprasellar central nervous system (CNS) embryonal tumors in adults are extremely rare. Hemorrhagic onset is further uncommon, with only anecdotic cases reported in the literature. The authors describe the case of a 57-year-old man affected by a suprasellar CNS embryonal tumor, with hemorrhagic onset and a unique diffusion pattern along the optic pathways.

MATERIAL AND METHODS

 A 57-year-old man presenting with acute visual acuity worsening and left homonymous hemianopia was referred to our hospital. Neuroradiologic studies demonstrated an infiltrating, high-grade lesion involving the optic chiasm and right retrochiasmatic pathways with a hemorrhagic area in the ipsilateral pulvinar.

RESULTS

 The patient underwent microsurgical biopsy. Pathologic assessment confirmed the diagnosis of CNS embryonal tumor, not otherwise specified (NOS) according to the 2016 World Health Organization (WHO) classification of CNS tumors. The patient was referred to a multimodal adjuvant treatment; he eventually died 4 months after surgery. Competent literature has been systematically reviewed in the light of the relevant changes made in the last version of the WHO classification.

CONCLUSION

 Embryonal tumors should be considered in the differential diagnosis for sellar and suprasellar space-occupying lesions, despite the rarity of the disease and the uncommon features at time of presentation. As per our knowledge, this is the first case ever described of hemorrhagic suprasellar embryonal tumor with a diffusion pattern along white matter fibers. Histogenesis, biomolecular and neuroradiologic features, and classification of embryonal tumors are an open field of research, with considerable implications for the definition of better diagnostic pitfalls and therapeutic regimens.

Tumor Location and Treatment Modality are Associated with Overall Survival in Adult Medulloblastoma

Introduction Medulloblastoma (MB) is an aggressive brain tumor most commonly found in children. Although prognostic factors are well studied in children, factors affecting survival in adults with medulloblastoma are unclear. Methods We queried the 1973-2015 United States Surveillance, Epidemiology, and End Results (SEER) registry to identify all adult cases of medulloblastoma, and performed multivariate survival analyses to assess the relationships amongst various clinical variables, including age, sex, race, tumor location, treatment modalities, and overall survival. Results A total of 857 patients, 20 years of age and older, with MB were identified in the SEER registry. Adult cases presented most frequently in the cerebellum (91.6%) compared to other less common regions (brain stem 3.2%, brain 2.2%, ventricle 1.8%). The overall median survival for adult MB is 60 months (SD = 94.3) and survival time is related to tumor location and course of treatment (P < 0.001). Multivariate Cox proportional hazard models showed that lesions found outside the cerebellum corresponded to worse median survival times (37 months) than those in the cerebellum (63 months) (hazard ratio 1.69, 95% CI 1.321-2.158, P = 0.001). Patients who were assigned chemotherapy had shorter survival (54 months) than those who were not (67 months) (HR 1.4515, 95% CI 1.26-1.671, P < 0.001), but receiving radiation therapy was associated with better overall survival (66 months) relative to not receiving radiation (25 months) (HR 0.581, 95% CI 0.48-0.70, P < 0.001). Conclusions Tumor location appears to be a significant prognostic factor for survival in adult MB. Recommended treatment regimes, likely reflective of the underlying aggressiveness of the tumor, also seem to impact survival.

Gamma Knife Surgery for Recurrent or Residual Supratentorial Primitive Neuroectodermal Tumors

BACKGROUND

Supratentorial primitive neuroectodermal tumors (PNETs) are highly malignant and rare tumors of the central nervous system.

OBJECTIVES

The aim of this study was to determine the role of Gamma Knife surgery (GKS) as a salvage treatment option for patients with recurrent or residual supratentorial PNETs.

METHODS

Between 1998 and 2014, 11 patients with supratentorial PNETs were retrospectively analyzed. This series consisted of 7 male and 4 female patients. The median age was 17 years. All patients received surgical resection followed by adjuvant therapy. The median time from operation to the first GKS treatment was 72.5 months. The median tumor volume was 17.5 cm3, and the median marginal dose was 11.5 Gy.

RESULTS

15 (65%) of the 23 tumors had been controlled. The actuarial local tumor control rate was 91% at 3 months, 73% at 6 months, and 44% at 12 months. At the time of analysis, 9 (82%) of the patients had died. The median survival time after the first GKS session was 17 months. The median survival time from the initial diagnosis was 65 months. No adverse radiation effect after GKS treatment occurred in any patient.

CONCLUSIONS

GKS treatment might be an effective salvage treatment option for recurrent or residual supratentorial PNETs after multimodal treatment.

Treatment Outcome and Prognostic Molecular Markers of Supratentorial Primitive Neuroectodermal Tumors

Background

To identify prognostic factors and define the optimal management of patients with supratentorial primitive neuroectodermal tumors (sPNETs), we investigated treatment outcomes and explored the prognostic value of specific molecular markers.

Methods

A total of 47 consecutive patients with pathologically confirmed sPNETs between May 1985 and June 2012 were included. Immunohistochemical analysis of LIN28, OLIG2, and Rad51 expression was performed and correlated with clinical outcome.

Results

With a median follow-up of 70 months, 5-year overall survival (OS) and progression-free survival (PFS) was 55.5% and 40%, respectively, for all patients. Age, surgical extent, and radiotherapy were significant prognostic factors for OS and PFS. Patients who received initially planned multimodal treatment without interruption (i.e., radiotherapy and surgery (≥subtotal resection), with or without chemotherapy) showed significantly higher 5-year OS (71.2%) and PFS (63.1%). In 29 patients with available tumor specimens, tumors with high expression of either LIN28 or OLIG2 or elevated level of Rad51 were significantly associated with poorer prognosis.

Conclusions

We found that multimodal treatment improved outcomes for sPNET patients, especially when radiotherapy and ≥subtotal resection were part of the treatment regimen. Furthermore, we confirmed the prognostic significance of LIN28 and OLIG2 and revealed the potential role of Rad51 in sPNETs.

Outcomes of adult medulloblastoma treated with a multimodality approach: A tertiary cancer center experience

OBJECTIVES

Adult medulloblastoma (AMB) is a rare central nervous system tumor. We aimed to analyze the treatment outcomes of AMB treated at our institute with surgery followed by craniospinal irradiation (CSI) and adjuvant chemotherapy.

METHODS

We retrospectively evaluated the treatment charts of 31 patients of AMB treated from 2003-2011. The patient demography, treatment details and survival data were collected in a predesigned proforma. Kaplan Meier method was used to analyze disease free survival (DFS) and the impact of prognostic factors was determined by univariate analysis (log rank test).

RESULTS

Male: Female ratio was 21:10. Cerebrospinal fluid dissemination was noted in 16% cases. CSI (36 Gray at 1.8 Gray/fraction to entire neuraxis and 20 Gray at 2 Gray/fraction boost to posterior fossa) was used in all cases. 26 patients received adjuvant chemotherapy (carboplatin plus etoposide). Median follows up was 26.85 months (9.47-119.73 months). The estimated 3 and 5 years DFS was found to be 84.9% and 50.7% respectively. On univariate analysis, tumor located laterally had a trend towards better DFS (HR 3.04; 95%CI 0.722 to 12.812; P = 0.07) compared to midline tumors. Other factors like adjuvant chemotherapy, age, gender, surgical extent had no statistically significant impact on survival.

CONCLUSION

The results of our study (largest series from India) show that the regimen of surgery, adjuvant CSI and chemotherapy is feasible and confers descent survival. AMB patients should be treated with a multimodality approach in a tertiary care centre.

[Molecular methods in diagnosis of poorly differentiated malignant brain tumors in children]

The histological diagnosis of malignant brain tumors in children is a complex process. In some cases, glioblastoma, primitive neuroectodermal tumor of the central nervous system, and atypical teratoid/rhabdoid tumor have a histological type similar to that of small blue round cell malignant tumor. Despite the similar histology, biological properties and approaches to treatment, these neoplasms are completely different and require their own treatment protocols. We retrospectively reviewed the most malignant types of childhood tumors and analyzed our own experience to propose a diagnostic algorithm for intracerebral small blue round cell malignant tumors in children based on the use of immunohistochemistry and fluorescence in situ hybridization.

Patterns of care in adult medulloblastoma: results of an international online survey

The literature on medulloblastoma in adults is generally limited to case reports and retrospective series, and there is no accepted standard of care. The Cooperative Trials Group for Neuro-Oncology (COGNO) sought to determine the range and consistency of clinicians' approaches to management as a basis for future trials. We aimed to identify current treatment strategies for adult medulloblastoma through an online survey launched at the 2012 Society of Neuro-Oncology meeting and by email invitation. Clinicians who had treated at least one adult patient with medulloblastoma, primitive neuroectodermal tumor (PNET), or pineoblastoma in the preceding year were asked about their most recent patient and invited to discuss their approach to a typical clinical scenario. Between November 2012 and January 2013, 45 clinicians (11 medical oncologists, 8 radiation oncologists, 5 pediatric oncologists, and 21 others) from Australia (24), United States (3), Europe (4) and other countries (14) completed the survey. Responding clinicians had treated 54 cases in the past 12 months. The most common histological type was medulloblastoma (64%), then PNET (20%). Most patients were male (68%), and had high-risk disease (65%). Complete surgical resection in 56 and 32% had molecular testing. Radiotherapy was predominantly cranio-spinal (92%) and given mostly post-resection (80%). Combination chemotherapy was more common than single-agent chemotherapy. The choice of chemotherapy varied considerably. There is substantial variation in the treatment of adult medulloblastoma, most pronounced in the choice of chemotherapeutic agents, highlighting the need for further collaborative research to guide evidence-based treatment strategies.