Dimitrios Mathios

BACKGROUND AND OBJECTIVES: Radiation-induced meningiomas (RIMs) are the most common secondary intracranial tumors. Compared with sporadic meningiomas (SMs), RIMs exhibit more aggressive clinical behavior. Surgical resection has traditionally been the primary treatment modality for these tumors; however, previous studies have demonstrated stereotactic radiosurgery (SRS) is an effective treatment for RIMs. The aims of this study were to further characterize these rare tumors and to directly compare the outcomes after SRS vs surgical resection as the primary treatment modality for RIMs. METHODS: A single-institution retrospective analysis of surgically and SRS-treated RIMs was conducted. Patient demographic data, World Health Organization grade, tumor volume, multiplicity, complications, and extent of resection were collected. The primary outcome was local control. RESULTS: Forty-seven patients with one or multiple RIMs comprising 73 tumors were identified and compared with a cohort of 75 patients with SMs (n = 86 tumors). Patients with RIMs more frequently harbored multiple tumors (44.4% vs 16.0%; P = .002). RIMs treated surgically exhibited a significantly worse local control compared with surgically treated SMs (log-rank P = .043). Among RIMs, primary treatment with SRS was associated with a significantly better local control compared with surgery as the primary treatment modality ( P = .011). SRS demonstrated superior 5- and 7-year local control rates even after controlling for size and restricting the analysis to gross totally resected tumors. CONCLUSION: SRS was associated with better local control compared with surgical resection for the primary treatment of RIMs. Frequent multifocal presentation and high rates of treatment failure support the notion that RIMs represent a distinct biological entity. Given the long latency and ongoing risk of tumor development after cranial irradiation, these findings underscore the importance of long-term surveillance in this patient population.

Extracranial metastasis of IDH-wildtype glioblastoma is very rare and poorly understood at the molecular level. We report a case of FGFR3::TACC3 fusion IDH-wildtype glioblastoma in a 61-year-old male, whose preoperative blood sample showed highly aberrant cfDNA fragmentation patterns, which could be suggestive of early systemic dissemination, undetected by standard-of-care imaging of his body. Eleven months post-resection and adjuvant therapy, he developed widespread extracranial metastases. Comprehensive molecular profiling of matched primary and metastatic tumors revealed broadly conserved genomic, transcriptomic, and copy number landscapes, with the metastasis harboring an additional ERCC6 deletion and enriched expression of receptor tyrosine kinase signaling genes. These findings provide rare insight into the genetic continuity and evolution underlying IDH-wildtype glioblastoma metastasis.

Background and importance: Atypical teratoid rhabdoid tumors (ATRTs) are typically aggressive pediatric tumors with a median survival of 11 months. Due to the paucity of cases in adults, the clinical behavior of these pathologies is not well understood. Here we present the case of a 41-year-old female patient with postoperative hyperprogression of a sellar ATRT and provide a detailed description of the molecular composition of this tumor, the protocol used to treat this patient, and the ultimate outcome of this patient.Clinical presentation: The patient is a 41-year-old woman who presented with headaches and double vision. MRI revealed a sellar/suprasellar mass with involvement of bilateral cavernous sinuses. Following the quick symptom progression, resection of the tumor with exploration of the bilateral cavernous sinuses was performed, with a final pathologic diagnosis of ATRT-MYC, a known subtype of ATRT. The tumor recurred within 1 month of surgery, attaining a size equivalent to its preoperative state. Postoperatively, the patient received craniospinal radiation and adjuvant chemotherapy with an excellent response but had a recurrence of the tumor in the brainstem 1 year after her diagnosis and died 13 months after presentation.Discussion: Sellar ATRT in adults is an exceedingly rare entity. The detailed description of our case highlights the aggressiveness of these tumors and the utility of postoperative chemotherapy and radiation, but also the inevitable progression of these tumors along the craniospinal axis.Conclusion: Sellar ATRTs should be considered in the differential diagnosis of a sellar/suprasellar mass, especially in women in their 40s. Emphasis should be placed on accurate diagnosis and quick postoperative recovery with early initiation of adjuvant radiation and chemotherapy.

Meningiomas are tumors of the central nervous system that vary in their presentation, ranging from benign and slow-growing to highly aggressive. The standard method for diagnosing and classifying meningiomas involves invasive surgery and can fail to provide accurate prognostic information. Liquid biopsy methods, which exploit circulating tumor biomarkers such as DNA, extracellular vesicles, micro-RNA, proteins, and more, offer a non-invasive and dynamic approach for tumor classification, prognostication, and evaluating treatment response. Currently, a clinically approved liquid biopsy test for meningiomas does not exist. This review provides a discussion of current research and the challenges of implementing liquid biopsy techniques for advancing meningioma patient care.