Citations

AbstractObjectiveTo profile clinically non‐aggressive and aggressive pituitary adenomas (PAs)/pituitary neuroendocrine tumours (PitNETs) and pituitary carcinomas for somatic mutations and epigenetic alterations of genes involved in cell proliferation/differentiation, microRNAs (miRNA)/long noncoding RNA (LncRNA)‐post‐transcriptional regulators and therapy targets.DesignRetrospective observational study.Patients and MeasurementsA total of 64 non‐aggressive and 41 aggressive PAs/PitNETs and 6 pituitary carcinomas treated by endoscopic surgery with ≥1‐year follow‐up were included. Somatic mutations of 17 genes and DNA methylation of 22 genes were assessed. Ten normal pituitaries were used as control.ResultsWe found at least one mutation in 17 tumours, including 6/64 non‐aggressive, 10/41 aggressive PAs/PitNETs, and 1/6 pituitary carcinoma. AIP (N = 6) was the most frequently mutated gene, followed by NOTCH (4), and TP53 (3). Hypermethylation of PARP15, LINC00599, ZAP70 was more common in aggressive than non‐aggressive PAs/PITNETs (p < .05). Lower levels of methylation of AIP, GNAS and PDCD1 were detected in aggressive PAs/PITNETs than non‐aggressive ones (p < .05). For X‐linked genes, males presented higher level of methylation of FLNA, UXT and MAGE family (MAGEA11, MAGEA1, MAGEC2) genes in aggressive vs. non‐aggressive PAs/PITNETs (p < .05).In pituitary carcinomas, methylation of autosomal genes PARP15, LINC00599, MIR193 and ZAP70 was higher than in PAs/PITNETs, while X‐linked genes methylation level was lower.ConclusionsSomatic mutations and methylation levels of genes involved in cell proliferation/differentiation, miRNA/LncRNA‐post‐transcriptional regulators and targets of antineoplastic therapies are different in non‐aggressive and in aggressive PAs/PitNETs. Methylation profile also varies according to gender. Combined genetic‐epigenetic analysis, in association with clinico‐radiological‐pathological data, may be of help in predicting PA/PitNET behaviour.

Abstract Primary leptomeningeal lymphoma is exceedingly rare. We describe 2 rare lymphoma cases with exclusive leptomeningeal disease: 1 ALK-positive (ALK+) anaplastic large cell lymphoma (ALCL) and 1 primary effusion lymphoma (PEL). Case 1: A 19-year-old man presented with symptoms concerning for leptomeningitis. Cerebrospinal fluid (CSF) analysis revealed lymphocytic pleocytosis. Spine MRI demonstrated pial enhancement from T10 through the conus medullaris and cauda equina enhancement/thickening. A biopsy showed leptomeningeal involvement by large lymphoma cells with hallmark cells and brisk mitotic activity. By immunohistochemistry, cells were CD7/CD30-positive with cytoplasmic ALK staining. No systemic disease was identified. The diagnosis of primary leptomeningeal ALK+ ALCL was made. Despite 2 CSF relapses requiring systemic therapy and autologous bone marrow transplant, the patient was in complete clinical remission 9 years after the diagnosis. Case 2: A 60-year-old, human immunodeficiency virus-positive man presented with symptoms suggestive of leptomeningitis. Brain MRIs revealed multifocal, supratentorial, and infratentorial leptomeningeal enhancement. A right frontal biopsy demonstrated leptomeningeal involvement by large lymphoma cells negative for B-cell immunostains, but CD138, MUM-1, and HHV8-positive, with aberrant CD3 expression. EBV-encoded RNA in situ hybridization was positive. In absence of solid lesions/extracranial involvement, the diagnosis of leptomeningeal PEL was rendered. Despite initial complete remission after chemotherapy, the patient died 9 months later.

Abstract Isocitrate dehydrogenase (IDH) 1 or 2 mutations confer a favorable prognosis compared to IDH-wildtype in astrocytoma, frequently denoting a lower grade malignancy. However, recent molecular profiling has identified specific aggressive tumor subgroups with clear clinical prognostic implications that are independent of histologic grading. The homozygous deletion of CDKN2A/B is the strongest implicated independent indicator of the poor prognosis within IDH-mutant astrocytoma, and the identification of this alteration in these lower histologic grade tumors transforms their biology toward an aggressive grade 4 phenotype clinically. CDKN2A/B homozygous deletion is now sufficient to define a grade 4 tumor in IDH-mutant astrocytomas regardless of histologic appearance, yet there are currently no effective molecularly informed targeted therapies for these tumors. The biological impact of CDKN2A/B homozygous deletion in IDH-mutant tumors and the optimal treatment strategy for this molecular subgroup remains insufficiently explored. Here we review the current understanding of the translational significance of homozygous deletion of CDKN2A/B gene expression in IDH-mutant astrocytoma and associated diagnostic and therapeutic implications.

Medulloblastoma (MB) is a malignant embryonal tumor of the posterior fossa belonging to the family of primitive neuro-ectodermic tumors (PNET). MB generally occurs in pediatric age, but in 14–30% of cases, it affects the adults, mostly below the age of 40, with an incidence of 0.6 per million per year, representing about 0.4–1% of tumors of the nervous system in adults. Unlike pediatric MB, robust prospective trials are scarce for the post-puberal population, due to the low incidence of MB in adolescent and young adults. Thus, current MB treatments for older patients are largely extrapolated from the pediatric experience, but the transferability and applicability of these paradigms to adults remain an open question. Adult MB is distinct from MB in children from a molecular and clinical perspective. Here, we review the management of adult MB, reporting the recent published literature focusing on the effectiveness of upfront chemotherapy, the development of targeted therapies, and the potential role of a reduced dose of radiotherapy in treating this disease.

Abstract Purpose Craniopharyngiomas are nonmalignant sellar and parasellar tumors exhibiting a bimodal age distribution. While the outcomes following treatment in patients with childhood-onset craniopharyngiomas are well characterized, similar information in adult-onset craniopharyngiomas is limited. We aimed to describe the long-term outcomes (weight and metabolic parameters, mortality) in patients with adult-onset craniopharyngioma following treatment. Methods: Patients with adult-onset craniopharyngioma with initial treatment (1993–2017) and > 6 months of follow-up at our institution were retrospectively identified. Body mass index (BMI) categories included obese (BMI ≥ 30 kg/m2), overweight (BMI 25-29.9 kg/m2), and normal weight (BMI < 25 kg/m2). Results For the 91 patients with adult-onset craniopharyngioma (44% women, mean diagnosis age 48.2 ± 18 years) over a mean follow-up of 100.3 ± 69.5 months, weight at last follow-up was significantly higher than before surgery (mean difference 9.5 ± 14.8 kg, P < 0.001) with a higher percentage increase in weight seen in those with lower preoperative BMI [normal weight (20.7 ± 18%) vs. overweight (13.3 ± 18.0%) vs. obese (6.4 ± 15%), P = 0.012. At last follow-up, the prevalence of obesity (62 vs. 40.5%, P = 0.0042) and impaired glucose metabolism (17.4% vs. 34%, P = 0.017) increased significantly. All-cause mortality was 12%, with the average age of death 71.9 ± 19.7 years (average U.S. life expectancy 77.7 years, CDC 2020). Conclusion Patients with adult-onset craniopharyngioma following treatment may experience weight gain, increased prevalence of obesity, impaired glucose metabolism, and early mortality. Lower preoperative BMI is associated with a greater percentage increase in postoperative weight.

2001 Background: PolyADP-ribose polymerase (PARP) is an important modulator of DNA repair following temozolomide (TMZ) therapy. Pre-clinical testing demonstrated significant survival benefit for the combination of TMZ and PARP inhibitor veliparib in a subset of GBM pt-derived xenografts with MGMT promoter hypermethylation. Methods: After central pathology review and MGMT testing, patients (pts) with newly diagnosed, MGMT promoter hypermethylated GBM who had completed concurrent radiation and TMZ were randomized to adjuvant therapy with TMZ (Days 1-5 q28 days) combined with either placebo or veliparib (Days 1-7 q28 days). Veliparib/placebo+TMZ treatment was continued for up to 6 cycles. Pts accrued on the phase II and III portions of the trial were included in the primary endpoint analysis of overall survival (OS), with 90% power to detect a hazard ratio of 0.71 using a one-sided log-rank test with type I error rate of 0.05. The planned phase III sample size was 400 pts with data maturity after 302 deaths. Results: The phase II and III portions of the trial were open to accrual from 12/15/2014 to 2/6/2017 and 11/8/2017 to 10/15/2018, respectively; 447 pts were accrued to the trial and used in this intention to treat analysis. The two treatment groups were well balanced for prognostic factors, 421 pts initiated treatment, median follow-up was 57.8 months (mos), 380 pts had disease progression and 335 pts have died. There was no difference in OS (p = 0.15; HR 0.89 (0.71-1.11), median OS 28.1 vs. 24.8 mo. for TMZ+veliparib vs. TMZ+placebo, respectively) and no difference in secondary endpoint progression free survival (PFS, p = 0.31; HR 1.05 (0.86-1.30), median 13.2 vs. 12.1 mo, respectively). There was a notable trend for extended OS with TMZ+veliparib treatment at intermediate time-points between 24 and 42 mos (3-year OS 36.6% vs. 28.9% with TMZ+placebo, p = 0.09). In an unplanned exploratory analysis, treatment with TMZ at the time of first recurrence was associated with extended post-recurrence OS (p = 0.03) for pts treated on the experimental arm; median post-recurrence OS with TMZ salvage was 17.0 mo in the TMZ+veliparib arm and 12.6 mo in the TMZ+placebo arm, as compared to 9.6 mo in either arm if TMZ salvage was not used. These data are consistent with a possible effect of veliparib limiting the emergence of TMZ resistance in a subset of GBM pts. Conclusions: Veliparib combined with adjuvant TMZ therapy was not associated with significant extension in OS or PFS in newly diagnosed, MGMT hypermethylated GBM pts. However, a subset of pts treated with TMZ+veliparib may have an extended survival following re-treatment with TMZ at first recurrence. Clinical trial information: NCT02152982.

Abstract Diffuse midline glioma (DMG) of the pons remains the leading cause of death among pediatric patients with brain tumors, despite numerous attempts to intensify treatment. While standard treatment includes 54Gy in 30 fractions of radiation over six weeks of time, nearly all patients progress within the treatment field, and many experience symptomatic radionecrosis with steroid dependence. Symptom improvement typically begins after 20Gy to the tumor. Both hypofractionation and reirradiation after recurrence have been found to be safe for patients with DMG. Our study aims to enroll patients with newly diagnosed pontine DMG aged &gt;1 year (no maximum age), and collect molecular information about DMG via stereotactic biopsy, followed by a short 2 week course of 25Gy in 10 fractions of radiation, with volumes guided by MRI with tractography reconstruction and FDOPA PET radiotracer uptake. Patients are followed closely and can complete the 25Gy in 10 fraction radiation course up to 3 times total for meeting radiographic and clinical progression criteria. Our primary endpoint is to estimate the time to progression from diagnosis to after receiving the second 25Gy course, and to compare this to the historical 7 month standard from diagnosis to progression after one 54Gy course. We aim to improve the time interval where patients are asymptomatic at home while minimizing time receiving daily treatments. Other endpoints will include the patient quality of life, caregiver quality of life, PFS intervals after each course, overall survival, and toxicity.

Abstract Atypical teratoid/rhabdoid tumor (AT/RT) is a malignant central nervous system tumor predominantly affecting infants. Mutations of SMARCB1 or (rarely) SMARCA4 causing loss of nuclear SMARCB1 or SMARCA4 protein expression are characteristic features, but further recurrent genetic alterations are lacking. Most AT/RTs occur de novo, but secondary AT/RTs arising in other central nervous system tumors have been reported. Malignant gliomas, IDH-wildtype, arising in patients with Li-Fraumeni syndrome typically show somatic mutations of TP53 as well as complex copy number alterations, but little is known about loss of SMARCB1 or SMARCA4 protein expression in this context. Here we report two children, in whom malignant supratentorial brain tumors with SMARCB1-deficiency, complex copy number alterations and somatic TP53 mutations lead to the discovery of pathogenic/likely pathogenic TP53 variants in the germ line. Screening of the molecularneuropathology.org data set for cases with similar genetic and epigenetic alterations yielded another case with SMARCA4-deficiency in a young adult with Li-Fraumeni syndrome. In conclusion, SMARCB1- or SMARCA4-deficient malignant brain tumors with complex copy number alterations and somatic TP53 mutations in children and young adults may represent the first clinical manifestation of Li-Fraumeni syndrome and should prompt genetic counseling and investigation for TP53 germline status.

Atypical teratoid/rhabdoid tumor (AT/RT) is a malignant central nervous system tumor predominantly affecting infants. Mutations of SMARCB1 or (rarely) SMARCA4 causing loss of nuclear SMARCB1 or SMARCA4 protein expression are characteristic features, but further recurrent genetic alterations are lacking. Most AT/RTs occur de novo, but secondary AT/RTs arising from other central nervous system tumors have been reported. Malignant gliomas, IDH wild-type, arising in patients with Li-Fraumeni syndrome typically show somatic mutations of TP53 as well as complex copy number alterations, but little is known about the loss of SMARCB1 or SMARCA4 protein expression in this context. Here, we report 2 children in whom malignant supratentorial brain tumors with SMARCB1 deficiency, complex copy number alterations, and somatic TP53 mutations lead to the discovery of pathogenic/likely pathogenic TP53 variants in the germline. Screening of the molecularneuropathology.org dataset for cases with similar genetic and epigenetic alterations yielded another case with SMARCA4 deficiency in a young adult with Li-Fraumeni syndrome. In conclusion, SMARCB1-deficient or SMARCA4-deficient malignant brain tumors with complex copy number alterations and somatic TP53 mutations in children and young adults may represent the first clinical manifestation of Li-Fraumeni syndrome and should prompt genetic counseling and investigation for TP53 germline status.