Medulloblastomas in adults: prognostic factors and lessons from paediatrics

An Adult Case of Medulloblastoma with Multiple Lung Metastatic Lesions-Case Report and Literature Review

Medulloblastoma (MB) cerebelli is a common brain tumor of the childhood. MB commonly spreads through cerebrospinal fluid; however, there are several reported cases of extracranial spread. The most common sites of extracranial metastasis are bones and bone marrow followed by peritoneum, liver, and lungs. Here, we report a case of pulmonary metastatic lesions of adult cerebellar MB that were discovered 1 year after the primary surgical treatment. We also tried to highlight similar reported cases in the literature.

Preradiation Chemotherapy for Adult High-risk Medulloblastoma: A Trial of the ECOG-ACRIN Cancer Research Group (E4397)

OBJECTIVES

To assess the long-term outcomes and objective response (OR) to preradiation chemotherapy and radiation in adult high-risk medulloblastoma.

MATERIALS AND METHODS

In this prospective phase II trial, adults with high-risk medulloblastoma were treated with 3 cycles of preradiation cisplatin, etoposide, cyclophosphamide, and vincristine followed by craniospinal radiation (CSI). OR, progression-free survival (PFS), overall survival (OS), and toxicities were assessed.

RESULTS

Eleven patients were enrolled over a 6-year period. Six (55%) had subarachnoid metastases. Two (18%) had an OR to preradiation chemotherapy. Two (18%) progressed while on chemotherapy. Completion of CSI was not compromised. The OR rate after chemotherapy and radiation was 45% (5/11). Nonevaluable patients at both time-points weakened the response data conclusions. Median PFS was 43.8 months. Five-year PFS was 27%. Five-year OS was 55%. Nonmetastatic (M0) and metastatic (M+) patients had similar outcomes.

CONCLUSIONS

The OR to this preradiation chemotherapy regimen is lower than anticipated from the adult and pediatric literature raising a question about comparative efficacy of chemotherapy in different age groups. The OS achieved is similar to retrospective adult series, but worse than pediatric outcomes. Although this regimen can be administered without compromising delivery of CSI, our results do not provide support for the use of this neoadjuvant chemotherapy for adult medulloblastoma.

Medulloblastoma: optimizing care with a multidisciplinary approach

Medulloblastoma is a malignant tumor of the cerebellum and the most frequent malignant brain tumor in children. The standard of care consists of maximal resection surgery, followed by craniospinal irradiation and chemotherapy. Such treatment allows long-term survival rates of nearly 70%; however, there are wide disparities among patient outcomes, and in any case, major long-term morbidity is observed with conventional treatment. In the last two decades, the molecular understanding of medulloblastoma has improved drastically, allowing us to revolutionize our understanding of medulloblastoma pathophysiological mechanisms. These advances led to an international consensus in 2010 that defined four prognostic molecular subgroups named after their affected signaling pathways, that is, WNT, SHH, Group 3 and Group 4. The molecular understanding of medulloblastoma is starting to translate through to clinical settings due to the development of targeted therapies. Moreover, recent improvements in radiotherapy modalities and the reconsideration of craniospinal irradiation according to the molecular status hold promise for survival preservation and the reduction of radiation-induced morbidity. This review is an overview of the current knowledge of medulloblastoma through a molecular approach, and therapeutic prospects currently being developed in surgery, radiotherapy and targeted therapies to optimize the treatment of medulloblastoma with a multidisciplinary approach will also be discussed.

Response assessment in medulloblastoma and leptomeningeal seeding tumors: recommendations from the Response Assessment in Pediatric Neuro-Oncology committee

Lack of standard response criteria in clinical trials for medulloblastoma and other seeding tumors complicates assessment of therapeutic efficacy and comparisons across studies. An international working group was established to develop consensus recommendations for response assessment. The aim is that these recommendations be prospectively evaluated in clinical trials, with the goal of achieving more reliable risk stratification and uniformity across clinical trials. Current practices and literature review were performed to identify major confounding issues and justify subsequently developed recommendations; in areas lacking scientific investigations, recommendations were based on experience of committee members and consensus was reached after discussion. Recommendations apply to both adult and pediatric patients with medulloblastoma and other seeding tumors. Response should be assessed using MR imaging (brain and spine), CSF cytology, and neurologic examination. Clinical imaging standards with minimum mandatory sequence acquisition that optimizes detection of leptomeningeal metastases are defined. We recommend central review prior to inclusion in treatment cohorts to ensure appropriate risk stratification and cohort inclusion. Consensus recommendations and response definitions for patients with medulloblastomas and other seeding tumors have been established; as with other Response Assessment in Neuro-Oncology recommendations, these need to now be prospectively validated in clinical trials.

Imaging Biomarkers for Adult Medulloblastomas: Genetic Entities May Be Identified by Their MR Imaging Radiophenotype

BACKGROUND AND PURPOSE

The occurrence of medulloblastomas in adults is rare; nevertheless, these tumors can be subdivided into genetic and histologic entities each having distinct prognoses. This study aimed to identify MR imaging biomarkers to classify these entities and to uncover differences in MR imaging biomarkers identified in pediatric medulloblastomas.

MATERIALS AND METHODS

Eligible preoperative MRIs from 28 patients (11 women; 22-53 years of age) of the Multicenter Pilot-study for the Therapy of Medulloblastoma of Adults (NOA-7) cohort were assessed by 3 experienced neuroradiologists. Lesions and perifocal edema were volumetrized and multiparametrically evaluated for classic morphologic characteristics, location, hydrocephalus, and Chang criteria. To identify MR imaging biomarkers, we correlated genetic entities sonic hedgehog (SHH) TP53 wild type, wingless (WNT), and non-WNT/non-SHH medulloblastomas (in adults, Group 4), and histologic entities were correlated with the imaging criteria. These MR imaging biomarkers were compared with corresponding data from a pediatric study.

RESULTS

There were 19 SHH TP53 wild type (69%), 4 WNT-activated (14%), and 5 Group 4 (17%) medulloblastomas. Six potential MR imaging biomarkers were identified, 3 of which, hydrocephalus (P = .03), intraventricular macrometastases (P = .02), and hemorrhage (P = .04), when combined, could identify WNT medulloblastoma with 100% sensitivity and 88.3% specificity (95% CI, 39.8%-100.0% and 62.6%-95.3%). WNT-activated nuclear β-catenin accumulating medulloblastomas were smaller than the other entities (95% CI, 5.2-22.3 cm³ versus 35.1-47.6 cm³; P = .03). Hemorrhage was exclusively present in non-WNT/non-SHH medulloblastomas (P = .04; n = 2/5). MR imaging biomarkers were all discordant from those identified in the pediatric cohort. Desmoplastic/nodular medulloblastomas were more rarely in contact with the fourth ventricle (4/15 versus 7/13; P = .04).

CONCLUSIONS

MR imaging biomarkers can help distinguish histologic and genetic medulloblastoma entities in adults and appear to be different from those identified in children.

The Neuroradiological Spectra of Adult and Pediatric Medulloblastoma Differ : Results from a Literature-based Meta-analysis

PURPOSE

Current knowledge on the spectrum of the neuroradiological appearance of adult medulloblastoma is sparse. Due to the rarity of the disease, adult patients were generally diagnosed and treated similar to children; however, pediatric and adult medulloblastomas display substantial molecular differences that may influence the neuroradiological phenotype. This study therefore aimed at assessment of the neuroradiological spectrum of adult medulloblastoma in comparison to pediatric tumors.

METHODS

All available publications on adult medulloblastoma published until June 2013 were screened for imaging data on single patients. A total of 109 patients were identified and compared to 118 pediatric patients described in 4 cohorts.

RESULTS

The average age of the adult patients was 34.3 years. Most adult medulloblastomas (57.6 %) were localized laterally (vs. 14.4 % in pediatric patients). On T1-weighted sequences, only 41.1 % of all adult medulloblastomas appeared hypointense (vs. 89.3 %) and 69.6 % were hyperintense on T2 sequences (vs. 83 %). In contrast to pediatric patients only 53.3 % showed strong contrast enhancement (pediatric patients 77.1 %), while the contrast uptake of the remainder was described as subtle, moderate or lacking. Contrast enhancement was more often described as inhomogeneous in adults (35.5 % as compared to 15.2 % in children) and 26.4 % had cysts.

CONCLUSION

Although the neuroradiological spectrum of medulloblastoma in adults was similar to children, an atypical presentation with inhomogeneous contrast enhancement, more hyperintense signal on T1 and a more hypointense signal on T2-weighted sequences was common. Given the rarity of the tumor, awareness of these differences constitutes a prerequisite to avoid delays in diagnostics.

Chemotherapy increases long-term survival in patients with adult medulloblastoma--a literature-based meta-analysis

BACKGROUND

Adult medulloblastoma is a potentially curable malignant entity with an incidence of 0.5-1 per million. Valid data on prognosis, treatment, and demographics are lacking, as most current knowledge stems from retrospective studies. Surgical resection followed by radiotherapy are accepted parts of treatment regimes; however, established prognostic factors and data clarifying the role of chemotherapy are missing.

METHODS

We investigated 227 publications from 1969-2013, with 907 identifiable, individual patients being available for meta-analysis. Demographic data, risk stratification, and treatment of these patients were similar to previous cohorts.

RESULTS

The median overall survival (mOS) was 65 months (95% CI: 54.6-75.3) , the 5-year overall survival was 50.9% with 16% of the patients dying more than 5 years after diagnosis. Incomplete resection, clinical and radiological signs for brainstem infiltration, and abstinence from radiotherapy were predictive of worse outcome. Metastatic disease at tumor recurrence was identified as a new prognostic factor, while neither metastasis at initial diagnosis nor desmoplastic/classic histology was correlated with survival. Patients receiving chemotherapy first-line survived significantly longer (mOS: 108 mo, 95% CI: 68.6-148.4) than patients treated with radiation alone (mOS: 57 mo, 95% CI: 39.6-74.4) or patients who received chemotherapy at tumor recurrence. This effect was not biased by tumor stage or decade of treatment. Importantly, (neo)adjuvant chemotherapy also significantly increased the chance for long-term survival (>5 y) compared with radiotherapy alone or chemotherapy at tumor recurrence.

CONCLUSIONS

This meta-analysis clarifies relevant prognostic factors and suggests that chemotherapy as part of first-line therapy improves overall survival and increases the proportion of patients with long-term survival.

Metastatic medulloblastoma in adults: outcome of patients treated according to the HIT2000 protocol

BACKGROUND

Due to the rarity of metastatic medulloblastoma in adults, knowledge about the efficacy and toxicity of intensified chemotherapy and radiotherapy is limited.

PATIENTS AND METHODS

Adults with disseminated medulloblastoma registered in the HIT2000 trial as observational patients and treated according to one of two different treatment regimens were analysed. The sandwich strategy MET-HIT2000AB4 consists of postoperative chemotherapy, hyperfractionated craniospinal radiotherapy, and maintenance chemotherapy; while the HIT'91 maintenance strategy consists of postoperative craniospinal radiotherapy, and maintenance chemotherapy.

RESULTS

Twenty-three patients (median age: 30.7years), diagnosed from November 2001 to July 2009, and treated in 18 institutions in Germany and Austria, were eligible. The median follow-up of surviving patients was 3.99years. The 4-year event-free survival (EFS) and overall survival (OS)±standard error (SE) were 52%±12% and 91%±6%, respectively. The survival was similar in both treatment groups (HIT'91 maintenance strategy, n=9; MET-HIT2000AB4 sandwich strategy, n=14). Patients with large cell/anaplastic medulloblastoma relapsed and died (n=2; 4-year EFS/OS: 0%) and OS differed compared to patients with classic (n=11; 4-year EFS/OS: 71%/91%) and desmoplastic medulloblastoma (n=10; 4-year EFS/OS: 48%/100%), respectively (p=0.161 for EFS and p=0.033 for OS). Treatment-induced toxicities consisted mainly of neurotoxicity (50% of patients, ⩾ °II), followed by haematotoxicity and nephrotoxicity/ototoxicity. The professional outcome appeared to be negatively affected in the majority of evaluable patients (9/10).

CONCLUSIONS

Treatment of adults with metastatic medulloblastoma according to the intensified paediatric HIT2000 protocol was feasible with acceptable toxicities. EFS rates achieved by both chemotherapeutic protocols were favourable and appear to be inferior to those obtained in older children/adolescents with metastatic disease.

ErbB2 signaling activates the Hedgehog pathway via PI3K-Akt in human esophageal adenocarcinoma: identification of novel targets for concerted therapy concepts

The Hedgehog pathway plays an important role in the pathogenesis of several tumor types, including esophageal cancer. In our study, we show an expression of the ligand Indian hedgehog (Ihh) and its downstream mediator Gli-1 in primary resected adenocarcinoma tissue by immunohistochemistry and quantitative PCR in fifty percent of the cases, while matching healthy esophagus mucosa was negative for both proteins. Moreover, a functionally important regulation of Gli-1 by ErbB2-PI3K-mTORC signaling as well as a Gli-1-dependent regulation of Ihh in the ErbB2 amplified esophageal adenocarcinoma cell line OE19 was observed. Treatment of OE19 cells with the Her2 antibody trastuzumab, the PI3K-mTORC1 inhibitor NVP BEZ235 (BEZ235) or the knockdown of Akt1 resulted in a downregulation of Gli-1 and Ihh as well as in a reduction of viable OE19 cells in vitro. Interestingly, the Hedgehog receptor Smo, which acts upstream of Gli-1, was not expressed in OE19 cells and in the majority of primary human esophageal adenocarcinoma, suggesting a non-canonical upregulation of Gli-1 expression by the ErbB2-PI3K axis. To translate our findings into a therapeutic concept, we targeted ErbB2-PI3K-mTORC1 by trastuzumab and BEZ235, combining both compounds with the Gli-1/2 inhibitor GANT61. The triple combination led to significantly stronger reduction of tumor cell viability than cisplatinum or each biological alone. Therefore, concomitant blockage of the ErbB2-PI3K pathway and the Hedgehog downstream mediator Gli-1 may provide a new therapeutic strategy for esophageal cancer.

Histological variants of medulloblastoma are the most powerful clinical prognostic indicators

BACKGROUND

Medulloblastoma histological classification has gained in importance and newer treatment protocols will include histology stratification. We centrally reviewed medulloblastoma cases from past 10 years reassessing their histology to ascertain its prognostic significance.

METHODS

Samples from 125 consecutive patients (99 males; 10 under age 3 years) were reviewed according to the two WHO classifications of 2000/2007.

RESULTS

Eighty-two patients did not have metastases, the primary tumor was completely resected in 101. The median follow-up was 96 months. Treatment was: our institutional protocol, that is, hyperfractionated accelerated radiotherapy (HART), for 39 non-metastatic cases up to 2003; according to the European PNET IV protocol in 31 cases; a HART-based strategy in 39 metastatic cases; tailored to the age below 3 years and based on high-dose chemotherapy in 10; and tailored to the patients conditions in 7. The 5-year PFS/OS rates were 76% and 81%, respectively. Histology was classic in 93 cases, nodular/desmoplastic in 20, anaplastic/large-cell in 9, and with extensive nodularity (MBEN) in 3. Stratification by residual disease after resection, metastases, age, or protocols was not prognostic. Histology suggested 5-year PFS rates of 82% for the desmoplastic and MBEN variants, 78% for classic medulloblastoma, 44% for the anaplastic/large-cell variants (P = 0.01). Multivariable analysis demonstrated statistically significant difference in PFS by histology (P = 0.02), due to the poor prognosis of anaplastic/large-cell medulloblastoma.

CONCLUSIONS

Tailoring treatments to known risk factors cancelled all prognostic differences, except for anaplasia (not considered as such within previous trials) which proved the most powerful prognostic factor, warranting appropriate treatment intensification.