Low-grade gliomas with the V600E mutation in the BRAF gene in children: clinical features and treatment options

The main pathogenetic mechanism of the development of pediatric low grade gliomas (pLGGs) is genetic aberrations in BRAF gene. This study is supported by the Independent Ethics Committee and approved by the Academic Council of the Dmitry Rogachev National Medical Research Center of Pediatric Hematology, Oncology, and Immunology. We analyzed the clinical and molecular characteristics of 69 patients with LGGs. Molecular genetic testing for BRAF V600E mutation was performed by allele-specific real-time PCR and Sanger sequencing. BRAF V600E mutation was detected in 15 (21.7%) patients with LGG. The majority of BRAF-mutated cases of LGGs had the midline location: OPG – 7, subcortical ganglia – 1, brainstem – 2. The 2-year PFS was much worse in patients with BRAF V600E compared to patients without this mutation – 30% and 66.2%, respectively. The median time to progression for patients with BRAF V600E mutation was 9.5 months compared to 3.1 years for patients without indicated substitution. 5 patients with BRAF V600E-mutated LGGs who experienced progression after the conventional treatment, received targeted therapy (BRAF-inhibitor-3, BRAF + MEK inhibitors – 2) with good response (complete response – 2, partial response – 3). BRAF V600E mutation contributes to poor outcome in patients with LGGs Targeted therapy could be effective in this cohort of patients.

Download Full-text

LGG-23. EXCELLENT CLINICAL / RADIOLOGICAL RESPONSE TO BRAF INHIBITION IN A YOUNG CHILD WITH IN-OPERABLE SUPRA-SELLAR PILOCYTIC ASTROCYTOMA

Neuro-Oncology ◽

10.1093/neuonc/noaa222.405 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii370-iii371

Author(s):

Stacy Chapman ◽

Demitre Serletis ◽

Colin Kazina ◽

Mubeen Rafay ◽

Sherry Krawitz ◽

...

Keyword(s):

Targeted Therapy ◽

Pilocytic Astrocytoma ◽

Clinical Symptoms ◽

Obstructive Hydrocephalus ◽

Braf V600e Mutation ◽

Braf V600e ◽

Low Grade ◽

Dramatic Improvement ◽

Chemotherapeutic Regimen ◽

Response To Chemotherapy

Abstract In-operable low grade gliomas (LGG) in the pediatric population continue to present a treatment dilemma. Due to the low-grade nature of these tumors, and variable response to chemotherapy / radiation, the choice of adjuvant treatment is difficult. Overall survival is directly related to the degree of surgical resection, adding complexity to these inoperable tumors. Current chemotherapeutic regimen for these inoperable tumors includes vincristine (VCR) and carboplatin (Carbo). With advancements in the molecular characterization of gliomas, the role of targeted therapy has come into question. We present a 2-year-old female with biopsy proven Pilocytic Astrocytoma (positive BRAF-V600E mutation) involving the hypothalamic/optic chiasm region. She presented with ataxic gait, bi-temporal hemianopia, obstructive hydrocephalus and central hypothyroidism, which progressed to altered consciousness, and right hemiparesis due to location/mass effect of the tumor. She was initially treated with chemotherapy (VCR/Carbo) but her tumor progressed at 6 weeks of treatment. As her tumor was positive for BRAF-V600E mutation, she was started on Dabrafenib monotherapy, resulting in dramatic improvement in her clinical symptoms (able to stand, improved vision), and a 60% reduction in tumor size at 3-months. At 6-months, follow up MRI showed slight increase in the solid portion of the tumor, with no clinical symptoms. We plan to add MEK inhibitor (Trametinib) and continue with Dabrafenib. Our experience and literature review suggests that LGG with BRAF-V600E mutations may benefit from upfront targeted therapy. Prospective clinical trials comparing the efficacy of BRAF inhibitors versus standard chemotherapy in LGG with BRAF mutations are urgently needed.

Download Full-text

Molecular Alterations in Pediatric Low-Grade Gliomas That Led to Death

Journal of Neuropathology & Experimental Neurology ◽

10.1093/jnen/nlab097 ◽

2021 ◽

Author(s):

Jared T Ahrendsen ◽

Claire Sinai ◽

David M Meredith ◽

Seth W Malinowski ◽

Tabitha M Cooney ◽

...

Keyword(s):

Braf V600e ◽

Molecular Characteristics ◽

Low Grade ◽

Diffuse Astrocytoma ◽

Term Survival ◽

Pten Loss ◽

Low Grade Gliomas ◽

Molecular Alterations ◽

Idh1 R132h ◽

Poor Outcomes

Abstract Pediatric low-grade gliomas (PLGGs) have excellent long-term survival, but death can occasionally occur. We reviewed all PLGG-related deaths between 1975 and 2019 at our institution: 48 patients were identified; clinical data and histology were reviewed; targeted exome sequencing was performed on available material. The median age at diagnosis was 5.2 years (0.4–23.4 years), at death was 13.0 years (1.9–43.2 years), and the overall survival was 7.2 years (0.0–33.3 years). Tumors were located throughout CNS, but predominantly in the diencephalon. Diagnoses included low-grade glioma, not otherwise specified (n = 25), pilocytic astrocytoma (n = 15), diffuse astrocytoma (n = 3), ganglioglioma (n = 3), and pilomyxoid astrocytoma (n = 2). Recurrence occurred in 42/48 cases, whereas progression occurred in 10. The cause of death was direct tumor involvement in 31/48 cases. Recurrent drivers included KIAA1549-BRAF (n = 13), BRAF(V600E) (n = 3), NF1 mutation (n = 3), EGFR mutation (n = 3), and FGFR1-TACC1 fusion (n = 2). Single cases were identified with IDH1(R132H), FGFR1(K656E), FGFR1 ITD, FGFR3 gain, PDGFRA amplification, and mismatch repair alteration. CDKN2A/B, CDKN2C, and PTEN loss was recurrent. Patients who received only chemotherapy had worse survival compared with patients who received radiation and chemotherapy. This study demonstrates that PLGG that led to death have diverse molecular characteristics. Location and co-occurring molecular alterations with malignant potential can predict poor outcomes.

Download Full-text

LGG-26. DIFFUSE LEPTOMENINGEAL GLIONEURONAL TUMOR (DLGNT) IN CHILDREN: DIFFERENT CLINICAL PRESENTATIONS AND OUTCOMES

Neuro-Oncology ◽

10.1093/neuonc/noaa222.408 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii371-iii371

Author(s):

Andge Valiakhmetova ◽

Ludmila Papusha ◽

Ludmila Yasko ◽

Alexander Druy ◽

Alexander Karachunsky ◽

...

Keyword(s):

Mapk Pathway ◽

Braf Inhibitor ◽

Complete Response ◽

Mek Inhibitor ◽

Braf V600e ◽

Glioneuronal Tumor ◽

Low Grade ◽

Conventional Chemotherapy ◽

Diffuse Leptomeningeal Glioneuronal Tumor ◽

Braf Fusion

Abstract Diffuse leptomeningeal glioneuronal tumor (DLGNT) is an extremely rare disease, newly recognized in the 2016 WHO classification of tumors of the CNS. Most DLGNTs are low-grade neuroepithelial tumors with variable elements of neuronal/neurocytic and glial differentiation, have diffuse leptomeningeal enhancement on MRI, and typically harbor KIAA1549-BRAF fusions. Other alterations, such as the BRAF V600E substitution, are less common. Here, we present three cases of DLGNT with different presentations and outcomes. The first patient is a 2yr-old male with KIAA1549-BRAF fusion, and was treated with Carbo/VCR chemotherapy after a biopsy, with resultant ongoing stable disease for 3.5 years. The second patient, an 8yr-old male had the BRAF V600E point mutation and was treated with conventional chemotherapy (VCR/carboplatin). On progression, he received the BRAF inhibitor vemurafenib, achieving a complete response which last 14 month. The third patient, a 27 month old male, harbored a KIAA1549-BRAF fusion and was treated at diagnosis with the MEK inhibitor trametinib. The tumor has been radiographically stable in the context of clinical improvement for 21 months since the treatment initiation, ongoing 24 month. In summary, we present further evidence of MAPK pathway alterations in children with DLGNT. We describe a range of molecular presentations and clinical outcomes, including one patient treated with conventional chemotherapy with further stabilization of disease during 3.5 years and two patients who were successfully treated with targeted therapy.

Download Full-text

Xenotransplantation of pediatric low grade gliomas confirms the enrichment of BRAF V600E mutation and preservation of CDKN2A deletion in a novel orthotopic xenograft mouse model of progressive pleomorphic xanthoastrocytoma

Oncotarget ◽

10.18632/oncotarget.20713 ◽

2017 ◽

Vol 8 (50) ◽

pp. 87455-87471 ◽

Cited By ~ 5

Author(s):

Mari Kogiso ◽

Lin Qi ◽

Holly Lindsay ◽

Yulun Huang ◽

Xiumei Zhao ◽

...

Keyword(s):

Mouse Model ◽

Pleomorphic Xanthoastrocytoma ◽

Braf V600e Mutation ◽

Braf V600e ◽

Low Grade ◽

Xenograft Mouse Model ◽

Low Grade Gliomas ◽

Orthotopic Xenograft ◽

Cdkn2a Deletion

Download Full-text

LGG-56. TREATMENT WITH VEMURAFENIB IN PEDIATRIC PATIENTS WITH LOW-GRADE GLIOMAS WITH BRAF V600E MUTATION. REPORT OF 4 CASES

Neuro-Oncology ◽

10.1093/neuonc/noy059.396 ◽

2018 ◽

Vol 20 (suppl_2) ◽

pp. i116-i116 ◽

Cited By ~ 1

Author(s):

María Cores ◽

Mariana Nana ◽

Paula Robledo ◽

Blanca Diez ◽

García Lombardi ◽

...

Keyword(s):

Pediatric Patients ◽

Braf V600e Mutation ◽

Braf V600e ◽

Low Grade ◽

Low Grade Gliomas

Download Full-text

Detection of BRAF V600E mutation by immunohistochemistry and PCR-RFLP in Moroccan patients with Pediatric Low-Grade Gliomas

Gene Reports ◽

10.1016/j.genrep.2019.100572 ◽

2020 ◽

Vol 18 ◽

pp. 100572

Author(s):

S. Hennani ◽

H. Dehbi ◽

S. Nadifi ◽

M. Karkouri

Keyword(s):

Braf V600e Mutation ◽

Braf V600e ◽

Low Grade ◽

Low Grade Gliomas ◽

Pcr Rflp ◽

Moroccan Patients

Download Full-text

HGG-06. REMARKABLE RESPONSE TO BRAF INHIBITOR IN AN INFANT WITH DISSEMINATED DIFFUSE LEPTOMENINGEAL GLIONEURONAL TUMOR (DLGNT)

Neuro-Oncology ◽

10.1093/neuonc/noaa222.297 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii345-iii345

Author(s):

Le Le Aung

Keyword(s):

Braf Inhibitor ◽

Braf V600e ◽

Proliferation Index ◽

Glioneuronal Tumor ◽

Low Grade ◽

Braf Inhibitors ◽

Visual Contact ◽

Ki 67 ◽

Low Grade Gliomas ◽

Diffuse Leptomeningeal Glioneuronal Tumor

Abstract INTRODUCTION Diffuse Leptomeningeal Glioneuronal Tumor (DLGNT) are rare CNS tumors and in infants, they can be lethal. There are several anecdotal reports in infants with low grade gliomas (LGG) with treated with BRAF inhibitors. METHODS A six-month old baby girl presented with a 2-week history of absent visual contact and vomiting. Imaging revealed a large 4.7 X 4.2 X 2.8 cm suprasellar charismatic region mass and multiple small extra-axial plaques in spinal canal. The child developed significant ascites post VP shunt requiring shunt externalization, extensive protein infusion support and hospitalization for six weeks. Immunohisto-chemical staining revealed Olig-2 and S-100, GFAP and synaptophysin positive. EMA showed patchy cytroplasmic reactivity in stromal cells and CD99 showed diffuse reactivity in stromal and lesional cells. INI-1, IDH-1, and CD117 were negative. Ki-67 proliferation index was 8–10%. PCR for BRAF V600E/E2/D was detected and KIAA1549-BRAF fusion as negative. This was confirmed by Genome Wide Next Generation Sequencing. While waiting for GNS testing results, the baby received one dose of Vinblastine. However, within seven days of initiating Debrafenib, significant clinical and radiological responses were observed. CONCLUSION The baby continues safely on Debrafenib with continued dramatic radiological response. This suggest that there may be a role in early initiation of targeted therapy such as BRAF inhibitors rather than giving standard chemotherapy such as Vinblastine or Carboplatin-Vincristine in extremely ill infants with low grade gliomas.

Download Full-text

CTNI-10. ADVANCES IN MANAGEMENT OF LOW-GRADE GLIOMAS

Neuro-Oncology ◽

10.1093/neuonc/noab196.235 ◽

2021 ◽

Vol 23 (Supplement_6) ◽

pp. vi61-vi61

Author(s):

Ruchi Raval ◽

Aadi Pandya ◽

Jaspreet Behl ◽

Sumul Raval

Keyword(s):

Treatment Plan ◽

Treatment Options ◽

Expression Patterns ◽

Molecular Genetic ◽

Tumor Resection ◽

Low Grade ◽

Low Grade Gliomas ◽

Wait And See ◽

Microsurgical Resection ◽

High Doses

Abstract BACKGROUND Low-grade gliomas (LGGs) are common benign brain tumors that arise from glial cells of the brain. The complex and variable backgrounds of LGGs cause difficulties in assigning therapies. In this report, we compile findings relating to LGG genetics and treatment options in order to create a coherent summary for referential use. METHODS We compiled 70 articles from the past ten years that cover a broad range of topics pertaining to LGGs, including molecular, genetic, epigenetic, morphological, and other diagnostic factors, as well as prognosis and treatment options. RESULTS In order to provide proper treatment, the molecular basis and histology of the tumor must be addressed. The 1p/19q co-deletion indicator has been considered the gold standard of glioma diagnosis, but oft-sighted mutations in the IDH1 and IDH2 genes have given rise to three subgroups of 1p/19q co-deleted tumors, each associated with specific patterns of nervous cells. Other molecular markers and microRNA expression patterns have been studied for possible diagnostic and prognostic methods. Microsurgical resection is the singular treatment with highest overall survival (OS) and quality of life (QOL). Total gross resection is optimal, with patients having a 5-year OS of 100% with 90% tumor resection. Low doses of radiation are as effective as high doses and are better tolerated (with less cognitive deficits). Chemotherapy, specifically temozolomide, offers a favorable toxicity profile and QOL; additionally, seizure reduction is an early and consistent prognostic marker for survival after treatment with temozolomide. CONCLUSIONS The “wait and see” approach for treatment is no longer the standard for LGGs. Immediate treatment after diagnosis is recommended. Gross total resection (if achievable) is the most favorable treatment, with the highest OS and QOL. The use of temozolomide and radiotherapy is recommended. Histological background and genetic markers are vital for determining a treatment plan.

Download Full-text

Response to Vemurafenib in Metastatic Triple-Negative Breast Cancer Harbouring a BRAF V600E Mutation: A Case Report and Electronically Captured Patient-Reported Outcome

Case Reports in Oncology ◽

10.1159/000513905 ◽

2021 ◽

pp. 616-621

Author(s):

Magdalena Pircher ◽

Thomas Winder ◽

Andreas Trojan

Keyword(s):

Breast Cancer ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Treatment Options ◽

Braf Inhibitor ◽

Local Therapy ◽

Braf V600e Mutation ◽

Braf V600e ◽

Breast Cancers ◽

Patient Reported

Effective treatment options are still scarce for metastatic triple-negative breast cancers. An increasing interest in the mutational landscape of this disease will facilitate novel therapeutic strategies in a variety of cancers. Here we report the case of a 38-year-old female patient who developed multiple lung metastasis of a triple-negative breast cancer 2 years after the completion of local therapy. When she progressed after two palliative chemotherapy lines and local electroporation, a next-generation sequencing revealed a BRAF V600E mutation for which we initiated therapy with the BRAF inhibitor vemurafenib. Radiological improvement was already evident after 3 months and has been ongoing for 19 months so far with very few side effects, as is demonstrated by electronically captured patient-reported outcomes. To our knowledge, this is the first published case where a BRAF V600E-mutated advanced triple-negative breast cancer was successfully treated with vemurafenib.

Download Full-text