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"Mafra, Manuela"
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Clinical insights gained by refining the 2016 WHO classification of diffuse gliomas with: EGFR amplification, TERT mutations, PTEN deletion and MGMT methylation
2019
Background
Significant advances in the molecular profiling of gliomas, led the 2016 World Health Organization (WHO) Classification to include, for the first-time, molecular biomarkers in glioma diagnosis:
IDH
mutations and 1p/19q codeletion. Here, we evaluated the effect of this new classification in the stratification of gliomas previously diagnosed according to 2007 WHO classification. Then, we also analyzed the impact of
TERT
promoter mutations,
PTEN
deletion,
EGFR
amplification and
MGMT
promoter methylation in diagnosis, prognosis and response to therapy in glioma molecular subgroup.
Methods
A cohort of 444 adult gliomas was analyzed and reclassified according to the 2016 WHO. Mutational analysis of
IDH1
and
TERT
promoter mutations was performed by Sanger sequencing. Statistical analysis was done using SPSS Statistics 21.0.
Results
The reclassification of this cohort using 2016 WHO criteria led to a decrease of the number of oligodendrogliomas (from 82 to 49) and an increase of astrocytomas (from 49 to 98), while glioblastomas (GBM) remained the same (
n
= 256). GBM was the most common diagnosis (57.7%), of which 55.2% were
IDH-
wildtype. 1p/19q codeleted gliomas were the subgroup associated with longer median overall survival (198 months), while GBM
IDH-
wildtype had the worst outcome (10 months). Interestingly,
PTEN
deletion had poor prognostic value in astrocytomas
IDH-
wildtype (
p
= 0.015), while in GBM
IDH-
wildtype was associated with better overall survival (
p
= 0.042) as well as
MGMT
promoter methylation (
p
= 0.009).
EGFR
amplification and
TERT
mutations had no impact in prognosis. Notably,
EGFR
amplification predicted a better response to radiotherapy (
p
= 0.011) and
MGMT
methylation to chemo-radiotherapy (
p
= 0.003).
Conclusion
In this study we observed that the 2016 WHO classification improved the accuracy of diagnosis and prognosis of diffuse gliomas, although the available biomarkers are not enough. Therefore, we suggest
MGMT
promoter methylation should be added to glioma classification. Moreover, we found two genetic/clinical correlations that must be evaluated to understand their impact in the clinical setting: i) how is
PTEN
deletion a favorable prognostic factor in GBM
IDH
wildtype and an unfavorable prognostic factor in astrocytoma
IDH
wildtype and ii) how
EGFR
amplification is an independent and strong factor of response to radiotherapy.
Journal Article
PIK3CA Mutations in Diffuse Gliomas: An Update on Molecular Stratification, Prognosis, Recurrence, and Aggressiveness
2022
Introduction:
PIK3CA is one of the most mutated oncogenes in solid tumors. In breast cancer (ER-positive, HER2-negative), these events represent a predictive biomarker of response to alpelisib. In glioblastomas (GBM), PIK3CA mutations were described as early constitutive events. Here, we investigated PIK3CA mutational profile across glioma molecular subgroups and its relevance during glioma recurrence. Furthermore, PIK3CA mutations’ effect in PI3K pathway, prognosis, and response to therapy was also explored.
Material and Methods:
Exons 10 and 21 of PIK3CA mutations were evaluated in 394 gliomas and 19 glioma recurrences from Instituto Português de Oncologia Lisboa Francisco Gentil (IPOLFG) and compared with The Cancer Genome Atlas (TCGA) data. TIMER2.0 and NetMHCpan4.1 were used to assess the immune-microenvironment contribution.
Results:
PIK3CA mutations were identified among all glioma subgroups, although with no impact on their stratification or prognosis. In both cohorts (IPOLFG and TCGA), PIK3CA mutation frequencies in IDH-mutant and IDH-wild-type GBM were similar (IPOLFG: 9% and 3%; TCGA: 8% and 2%). These mutations were not mutually exclusive with PTEN deletion and EGFR amplification. Despite their reduced frequency, we discovered PIK3CA mutations were maintained during glioma recurrence regardless of administered therapies. The immune microenvironment might not contribute to this phenotype as PIK3CA mutations did not influence immune cell infiltration.
Conclusions:
Despite the absence of a predominant effect in glioma stratification, PIK3CA mutations were maintained during glioma recurrence, possibly contributing to glioma cell survival, representing promising therapeutic targets in recurrent glioma. Nevertheless, understanding the potential synergistic effects between PIK3CA mutations, PTEN deletion, and EGFR amplification is pivotal to targeted therapies’ efficiency.
Journal Article
BRAF V600E mutation and 9p21: CDKN2A/B and MTAP co-deletions - Markers in the clinical stratification of pediatric gliomas
by
do Carmo Martins, Maria
,
Pimentel, José
,
Sagarribay, Amets
in
5'-Methylthioadenosine phosphorylase
,
9p21 chromosomal region
,
Analysis
2018
Background
Genetic alterations in pediatric primary brain tumors can be used as diagnostic and prognostic markers and are the basis for the development of new target therapies that, ideally, would be associated with lower mortality and morbidity. This study evaluates the incidence and interplay of the presence of
BRAF V600E
mutation and chromosomal 9p21 deletions in a series of 100 pediatric gliomas, aiming to determine the role of these alterations in recurrence and malignant transformation, and to verify if they could be used in the clinical set for stratifying patients for tailored therapies and surveillance.
Methods
Sanger sequencing was used for the assessment of
BRAF
mutations at exon 15 and
Fluorescent
In Situ
Hybridization (FISH)
with BAC: RP11–14192 for the detection of 9p21 alterations. Expression levels of the
CDKN2A
and
MTAP
by real-time PCR were evaluated in cases with 9p21 deletions. Statistical analysis of genetic and clinical data was performed using
Graph Pad Prism 5
and
SPSS Statistics 24
software.
Results
In our cohort it was observed that 7 /78 (8,9%) of the low-grade tumors recurred and 2 (2,6%) showed malignant transformation.
BRAF V600E
mutations were detected in 15 cases. No statistically significant correlations were found between the presence of
BRAF V600E
mutation and patient’s morphologic or clinical features. Deletions at 9p21 abrogating the
CDKN2A/B
and
MTAP
loci were rare in grade I gliomas (12.2%,
p
= 0.0178) but frequent in grade IV gliomas (62.5%,
p
= 0.0087). Moreover it was found that deletions at these loci were correlated with a shorter overall survival (
p
= 0.011) and a shorter progression-free survival (
p
= 0.016).
Conclusions
It was demonstrated that in these tumors
BRAF V600E
mutated and that
CDKN2A/B MTAP
co-deletions may be used for stratifying patients for a stricter surveillance. The Investigating and defining if glial tumors with
CDKN2A/B
and
MTAP
homozygous loss may be vulnerable to new forms of therapy, namely those affecting the methionine salvage pathway, was proven to be of importance.
Journal Article
Glioblastoma zebrafish Avatars guide therapeutic decisions in a patient with gliosarcoma: a case report
2025
Background
Glioblastoma is the most common and lethal brain tumor. Therapeutic options after recurrence are scarce and with no agreement as to which treatment to offer. Also, no functional tests are currently in use to guide clinical decisions. As a result, patients often undergo multiple treatments, being exposed to toxicities and wasting valuable time.
Methods
Here we report a case of a 37-year-old man with a left temporal glioblastoma (gliosarcoma subtype), who underwent several surgeries and treatments. Tumor DNA sequencing revealed no actionable mutations. At the second recurrence, brain MRI showed three new left-hemisphere nodular lesions, leading to a third surgery. However, twenty-days post-surgery the patient relapsed. Therapeutic options available for this patient were no longer well defined and 13 possible off-label options emerged. Fresh tumor samples were used to generate patient-derived zebrafish xenografts (zAvatars) to test the 13 options in combination with radiotherapy.
Results
Pemetrexed, and Pemetrexed with Doxorubicin together with Radiotherapy, were both effective in inducing apoptosis. Due to toxicity concerns, the physician opted for the combination of radiotherapy and pemetrexed, with doxorubicin introduced later. The patient recovered and was stable for two months, consistent with the zAvatar prediction.
Conclusions
The rapid establishment of zAvatars from glioblastoma tumor samples allows for the testing of drug combinations and the tailoring of treatment in a personalized and timely manner. A future pipeline of tumor sequencing together with zAvatars testing, since the first surgery, may help manage patients more effectively, potentially improving their Progression free survival (PFS) and overall survival (OS).
Plain language summary
Glioblastoma is the most aggressive type of brain tumor, with limited treatment options and poor prognosis. We report the case of a 37-year-old man with recurrent glioblastoma. After his third surgery, the tumor rapidly recurred, and various treatment options were considered. To guide the decision, tumor cells from the patient were implanted into zebrafish embryos to create “zAvatars,” which were then treated with the 13 therapies and radiotherapy. Two treatment options resulted in more tumor killing in the zAvatars. The patient was treated according to the zAvatar-test, stabilizing the patient for two months. Our findings show that zAvatars could be used to rapidly evaluate multiple therapy options, enabling doctors to tailor treatments in a personalized manner.
Fontes et al. report a case study of a person with recurrent glioblastoma for whom patient-derived zebrafish xenografts (zAvatars) were used to test 13 off-label therapies with radiotherapy. zAvatars identified pemetrexed and doxorubicin as effective, guiding treatment that stabilized the patient.
Journal Article
Metastatic pituitary neuroendocrine neoplasms: A case report of a malignant prolactinoma
2024
Key Clinical Message We report a rare clinical case of a malignant prolactinoma in which the exponential increase of prolactin levels with minimal tumor growth and no response to treatment led to diagnosis of abdominal, thoracic, and vertebral metastases. Aggressiveness of a malignant prolactinoma
Journal Article
Pituitary metastasis as the first manifestation of lung carcinoma
2022
Pituitary metastases are rare. Clinical presentation could range from asymptomatic to panhypopituitarism or local symptoms. We present a case report of a 43‐year‐old male patient with a new onset headache, visual disturbances, and panhypopituitarism. The investigation led to the diagnosis of pituitary metastasis as the first manifestation of underlying lung cancer. With rising incidence of breast and lung malignancy, headache/visual field disturbance or signs of pituitary hormone deficiency might be the presenting feature of pituitary metastatic disease. A rapid growth of a sellar lesion and/or the presence of diabetes insipidus along with a sellar mass should raise the suspicion for malignancy.
Journal Article
Right cardiac intracavitary metastases from a primary intracranial myxofibrosarcoma
2016
Primary intracranial myxofibrosarcoma is exceedingly rare, with less than 10 cases published. We present a case of a 23-year-old man with previous history of a primary low grade myxofibrosarcoma of the left parietal-occipital convexity resected in March 1999. He subsequently underwent several interventions for multiple local recurrent disease until March 2004. At that time, complete remission was documented. About 8 years later, in February 2012, the patient was admitted to the emergency room with refractory acute pulmonary oedema. On work up, sustained monomorphic ventricular tachycardia and hyperechoic myocardial mass with invasion of the right ventricular cavity were detected. Electrical cardioversion was unsuccessful and irreversible cardiac arrest followed. The autopsy confirmed multiple bilateral lung metastases, malignant pulmonary embolism and myocardial invasion by the primary tumour, with intracavitary cardiac thrombosis and absence of intracranial disease. To the best of our knowledge, this is the first report of extracranial metastases of this neoplasm.
Journal Article
Intracranial mesenchymal tumor with FET‐CREB fusion—A unifying diagnosis for the spectrum of intracranial myxoid mesenchymal tumors and angiomatoid fibrous histiocytoma‐like neoplasms
2021
Intracranial mesenchymal tumors with FET‐CREB fusions are a recently described group of neoplasms in children and young adults characterized by fusion of a FET family gene (usually EWSR1, but rarely FUS) to a CREB family transcription factor (ATF1, CREB1, or CREM), and have been variously termed intracranial angiomatoid fibrous histiocytoma or intracranial myxoid mesenchymal tumor. The clinical outcomes, histologic features, and genomic landscape are not well defined. Here, we studied 20 patients with intracranial mesenchymal tumors proven to harbor FET‐CREB fusion by next‐generation sequencing (NGS). The 16 female and four male patients had a median age of 14 years (range 4–70). Tumors were uniformly extra‐axial or intraventricular and located at the cerebral convexities (n = 7), falx (2), lateral ventricles (4), tentorium (2), cerebellopontine angle (4), and spinal cord (1). NGS demonstrated that eight tumors harbored EWSR1‐ATF1 fusion, seven had EWSR1‐CREB1, four had EWSR1‐CREM, and one had FUS‐CREM. Tumors were uniformly well circumscribed and typically contrast enhancing with solid and cystic growth. Tumors with EWSR1‐CREB1 fusions more often featured stellate/spindle cell morphology, mucin‐rich stroma, and hemangioma‐like vasculature compared to tumors with EWSR1‐ATF1 fusions that most often featured sheets of epithelioid cells with mucin‐poor collagenous stroma. These tumors demonstrated polyphenotypic immunoprofiles with frequent positivity for desmin, EMA, CD99, MUC4, and synaptophysin, but absence of SSTR2A, myogenin, and HMB45 expression. There was a propensity for local recurrence with a median progression‐free survival of 12 months and a median overall survival of greater than 60 months, with three patients succumbing to disease (all with EWSR1‐ATF1 fusions). In combination with prior case series, this study provides further insight into intracranial mesenchymal tumors with FET‐CREB fusion, which represent a distinct group of CNS tumors encompassing both intracranial myxoid mesenchymal tumor and angiomatoid fibrous histiocytoma‐like neoplasms. Intracranial mesenchymal tumors with FET‐CREB fusion comprise a group of neoplasms that have been variably described as intracranial angiomatoid fibrous histiocytoma and intracranial myxoid mesenchymal tumor. Our investigation reveals that these tumors occur in a wide age range with a female predominance, usually have extra‐axial or intraventricular location, typically have solid and cystic growth pattern with enhancement after contrast administration, and demonstrate a propensity for local recurrence and occasionally dissemination or metastasis leading to mortality. These tumors demonstrate a broad range of histologic features, with those harboring CREB1 or CREM as the fusion partner enriched for stellate/spindle cell morphology and mucin‐rich stroma, versus those with ATF1 as the fusion partner enriched for epithelioid/rhabdoid morphology and mucin‐poor stroma.
Journal Article
Mixed testicular germ cell tumour in a patient with previous pineal germinoma
by
Bravo-Marques, José M.
,
Mafra, Manuela S.
,
Azevedo, Ana L.
in
Adolescent
,
Adult
,
Antineoplastic Combined Chemotherapy Protocols - therapeutic use
2011
Germ cell tumours (GCT) are a relatively common malignancy in men aged 15–35 years. They occur most frequently in the gonads, but 3–5% have extragonadal origin, mainly in the pineal gland, neurohypophysis, mediastinum and retroperitoneum. Although intracranial germinomas may present with synchronous midline lesions, development of metachronous testicular germ cell primaries seems to be extremely rare, and confirmed dissemination of intracranial GCT to the testes has never been reported. We report the case of a 32-year-old man, with previously treated pineal germinoma at age 16 years, who later developed mixed GCT of the left testis.
Journal Article