A multi-institutional meningioma MRI dataset for automated multi-sequence image segmentation.

Meningiomas are the most common primary intracranial tumors and can be associated with significant morbidity and mortality. Radiologists, neurosurgeons, neuro-oncologists, and radiation oncologists rely on brain MRI for diagnosis, treatment planning, and longitudinal treatment monitoring. However, automated, objective, and quantitative tools for non-invasive assessment of meningiomas on multi-sequence MR images are not available. Here we present the BraTS Pre-operative Meningioma Dataset, as the largest multi-institutional expert annotated multilabel meningioma multi-sequence MR image dataset to date. This dataset includes 1,141 multi-sequence MR images from six sites, each with four structural MRI sequences (T2-, T2/FLAIR-, pre-contrast T1-, and post-contrast T1-weighted) accompanied by expert manually refined segmentations of three distinct meningioma sub-compartments: enhancing tumor, non-enhancing tumor, and surrounding non-enhancing T2/FLAIR hyperintensity. Basic demographic data are provided including age at time of initial imaging, sex, and CNS WHO grade. The goal of releasing this dataset is to facilitate the development of automated computational methods for meningioma segmentation and expedite their incorporation into clinical practice, ultimately targeting improvement in the care of meningioma patients.

A Case Report of the Clinico-radiologic Challenges of Assessing Treatment Response after Stereotactic Radiation of Oligometastases Preceded by Immunotherapy: Pseudoprogression, Mixed Response Patterns, and Opportunities for Precision Radiation.

As immunotherapy continues to translate to the clinic and is combined with existing modalities, such as radiation therapy, novel treatment response patterns have been observed which complicate conventional clinical assessment and management. Herein, we describe a case study of a patient with non-small cell lung cancer treated initially with definitive chemoradiation who subsequently developed oligorecurrent disease which was managed with nivolumab and then comprehensive salvage stereotactic radiation. Serial radiographic assessment had shown worsening at these limited sites of disease after initiating immunotherapy, improvement after radiation, and then heterogeneous response behavior across sites during longer-term follow-up. Given the dual effects ablative radiation may have in the context of global immune checkpoint inhibition, both cytotoxic and synergistic immune-related, assessment of treatment response to such treatment is complicated. Such assessment is further complicated by novel immunotherapy response phenomena, e.g. pseudoprogression, which are being uncovered and are not fully characterized. Current clinical and radiologic assessment strategies are inadequate to interrogate and discern between immunomodulation-influenced response behavior and further diagnostic innovation is warranted to meet the needs of evolving clinical practice in the era of immunotherapy.

Reirradiation for Recurrent Pediatric Central Nervous System Malignancies: A Multi-institutional Review.

PURPOSE: Reirradiation has been proposed as an effective modality for recurrent central nervous system (CNS) malignancies in adults. We evaluated the toxicity and outcomes of CNS reirradiation in pediatric patients. METHODS AND MATERIALS: The data from pediatric patients <21 years of age at the initial diagnosis who developed a recurrent CNS malignancy that received repeat radiation therapy (RT) across 5 facilities in an international pediatric research consortium were retrospectively reviewed. RESULTS: Sixty-seven pediatric patients underwent CNS reirradiation. The primary diagnoses included medulloblastoma/primitive neuroectodermal tumor (n=20; 30%), ependymoma (n=19; 28%), germ cell tumor (n=8; 12%), high-grade glioma (n=9; 13%), low-grade glioma (n=5; 7%), and other (n=6; 9%). The median age at the first course of RT was 8.5 years (range 0.5-19.5) and was 12.3 years (range 3.3-30.2) at reirradiation. The median interval between RT courses was 2.0 years (range 0.3-16.5). The median radiation dose and fractionation in equivalent 2-Gy fractions was 63.7 Gy (range 27.6-74.8) for initial RT and 53.1 Gy (range 18.6-70.1) for repeat RT. The relapse location was infield in 52 patients (78%) and surrounding the initial RT field in 15 patients (22%). Thirty-seven patients (58%) underwent gross or subtotal resection at recurrence. The techniques used for reirradiation were intensity modulated RT (n=46), 3-dimensional conformal RT (n=9), stereotactic radiosurgery (n=4; 12-13 Gy × 1 or 5 Gy × 5), protons (n=4), combined modality (n=3), 2-dimensional RT (n=1), and brachytherapy (n=1). Radiation necrosis was detected in 2 patients after the first RT course and 1 additional patient after reirradiation. Six patients (9%) developed secondary neoplasms after initial RT (1 hematologic, 5 intracranial). One patient developed a secondary neoplasm identified shortly after repeat RT. The median overall survival after completion of repeat RT was 12.8 months for the entire cohort and 20.5 and 8.4 months for patients with recurrent ependymoma and medulloblastoma after reirradiation, respectively. CONCLUSIONS: CNS reirradiation in pediatric patients could be a reasonable treatment option, with moderate survival noted after repeat RT. However, prospective data characterizing the rates of local control and toxicity are needed.