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.

The Brain Tumor Segmentation (BraTS) Challenge 2023: Focus on Pediatrics (CBTN-CONNECT-DIPGR-ASNR-MICCAI BraTS-PEDs)

Pediatric tumors of the central nervous system are the most common cause of cancer-related death in children. The five-year survival rate for high-grade gliomas in children is less than 20\%. Due to their rarity, the diagnosis of these entities is often delayed, their treatment is mainly based on historic treatment concepts, and clinical trials require multi-institutional collaborations. The MICCAI Brain Tumor Segmentation (BraTS) Challenge is a landmark community benchmark event with a successful history of 12 years of resource creation for the segmentation and analysis of adult glioma. Here we present the CBTN-CONNECT-DIPGR-ASNR-MICCAI BraTS-PEDs 2023 challenge, which represents the first BraTS challenge focused on pediatric brain tumors with data acquired across multiple international consortia dedicated to pediatric neuro-oncology and clinical trials. The BraTS-PEDs 2023 challenge focuses on benchmarking the development of volumentric segmentation algorithms for pediatric brain glioma through standardized quantitative performance evaluation metrics utilized across the BraTS 2023 cluster of challenges. Models gaining knowledge from the BraTS-PEDs multi-parametric structural MRI (mpMRI) training data will be evaluated on separate validation and unseen test mpMRI dataof high-grade pediatric glioma. The CBTN-CONNECT-DIPGR-ASNR-MICCAI BraTS-PEDs 2023 challenge brings together clinicians and AI/imaging scientists to lead to faster development of automated segmentation techniques that could benefit clinical trials, and ultimately the care of children with brain tumors.

Clinical Efficacy and Safety of Once-Weekly Fractionation in Stereotactic Body Radiotherapy for Pulmonary Oligometastatic Lesions

PURPOSE/OBJECTIVE(S)

As the oligometastatic disease paradigm has become more widely accepted, further investigation is needed to risk-stratify patients within this spectrum of disease and define optimal treatment methods. Stereotactic Body Radiotherapy (SBRT) has emerged as an efficacious and safe modality to control individual lesions and improve clinical outcomes in the setting of oligometastatic disease. There is scant literature describing ideal SBRT inter-fraction time intervals or their impact on clinical outcomes, especially for treating pulmonary oligometastases. Most institutions appear to offer treatments on consecutive days or every other day. In this abstract, we sought to evaluate the efficacy and safety of delivering SBRT treatments in a once-weekly fractionation scheme.

MATERIALS/METHODS

The study was undertaken via retrospective review at a single institution. We included patients with pulmonary metastatic lesions treated with SBRT at our institution between 2015 and 2019. Patients with oligometastatic disease were included, defined as patients with 5 or fewer total metastatic lesions. Treatments were delivered between 3 and 5 fractions and using at least 5 Gy per fraction. Per institutional protocol, all treatments were delivered 7 days apart.

RESULTS

From a single institution, 204 lesions from 111 patients were included. Median follow-up was 16.5 months [IQR 7 - 36.3]. Median dose was 40 Gy [IQR 30 - 50], median BED was 80 Gy [IQR 60-100], median dose per fraction was 10 Gy [IQR 8-11]. Median internal target volume (ITV) was 18.5 cc [IQR 9.3 - 45.8]. The most common tumor histologies were lung adenocarcinoma (38.2%), colorectal adenocarcinoma (15.6%), lung squamous cell carcinoma (12.7%), renal cell carcinoma (5.9%), breast invasive ductal carcinoma (5.4%), small cell lung cancer (3.9%), and melanoma (2.9%). 2-year local control (LC) rate was 85.7% and 5-year LC rate was 84.3%. 2-year regional control (RC) rate was 53.9% and 5-year RC was 49%. Median overall survival (OS) was 20 months [IQR 9 - 37.3]. Cox regression analysis revealed biologically effective dose (BED) (HR 0.99 [0.98 - 0.99] p = 0.001) as well as dose per fraction (HR 0.92 [0.86 - 0.97] p = 0.003) were both associated with improved OS. Longest tumor dimension was associated with worse OS independent of BED and dose per fraction (HR 1.26 [1.1 - 1.4] p = 0.001). Total toxicity incidence was 7.3%, which consisted only of G1-G2 cough, dyspnea, and fatigue.

CONCLUSION

Treatment of pulmonary oligometastatic lesions with SBRT delivered via once-weekly fractionation is associated with excellent local control and minimal toxicity. Larger studies are warranted to directly compare clinical outcomes of weekly SBRT fractionation to other conventional SBRT treatment schedules.

The Brain Tumor Segmentation (BraTS) Challenge 2023: Brain MR Image Synthesis for Tumor Segmentation (BraSyn)

Automated brain tumor segmentation methods have become well-established and reached performance levels offering clear clinical utility. These methods typically rely on four input magnetic resonance imaging (MRI) modalities: T1-weighted images with and without contrast enhancement, T2-weighted images, and FLAIR images. However, some sequences are often missing in clinical practice due to time constraints or image artifacts, such as patient motion. Consequently, the ability to substitute missing modalities and gain segmentation performance is highly desirable and necessary for the broader adoption of these algorithms in the clinical routine. In this work, we present the establishment of the Brain MR Image Synthesis Benchmark (BraSyn) in conjunction with the Medical Image Computing and Computer-Assisted Intervention (MICCAI) 2023. The primary objective of this challenge is to evaluate image synthesis methods that can realistically generate missing MRI modalities when multiple available images are provided. The ultimate aim is to facilitate automated brain tumor segmentation pipelines. The image dataset used in the benchmark is diverse and multi-modal, created through collaboration with various hospitals and research institutions.

The Brain Tumor Segmentation (BraTS) Challenge 2023: Glioma Segmentation in Sub-Saharan Africa Patient Population (BraTS-Africa)

Gliomas are the most common type of primary brain tumors. Although gliomas are relatively rare, they are among the deadliest types of cancer, with a survival rate of less than 2 years after diagnosis. Gliomas are challenging to diagnose, hard to treat and inherently resistant to conventional therapy. Years of extensive research to improve diagnosis and treatment of gliomas have decreased mortality rates across the Global North, while chances of survival among individuals in low- and middle-income countries (LMICs) remain unchanged and are significantly worse in Sub-Saharan Africa (SSA) populations. Long-term survival with glioma is associated with the identification of appropriate pathological features on brain MRI and confirmation by histopathology. Since 2012, the Brain Tumor Segmentation (BraTS) Challenge have evaluated state-of-the-art machine learning methods to detect, characterize, and classify gliomas. However, it is unclear if the state-of-the-art methods can be widely implemented in SSA given the extensive use of lower-quality MRI technology, which produces poor image contrast and resolution and more importantly, the propensity for late presentation of disease at advanced stages as well as the unique characteristics of gliomas in SSA (i.e., suspected higher rates of gliomatosis cerebri). Thus, the BraTS-Africa Challenge provides a unique opportunity to include brain MRI glioma cases from SSA in global efforts through the BraTS Challenge to develop and evaluate computer-aided-diagnostic (CAD) methods for the detection and characterization of glioma in resource-limited settings, where the potential for CAD tools to transform healthcare are more likely.

The ASNR-MICCAI Brain Tumor Segmentation (BraTS) Challenge 2023: Intracranial Meningioma

Meningiomas are the most common primary intracranial tumor in adults and can be associated with significant morbidity and mortality. Radiologists, neurosurgeons, neuro-oncologists, and radiation oncologists rely on multiparametric MRI (mpMRI) for diagnosis, treatment planning, and longitudinal treatment monitoring; yet automated, objective, and quantitative tools for non-invasive assessment of meningiomas on mpMRI are lacking. The BraTS meningioma 2023 challenge will provide a community standard and benchmark for state-of-the-art automated intracranial meningioma segmentation models based on the largest expert annotated multilabel meningioma mpMRI dataset to date. Challenge competitors will develop automated segmentation models to predict three distinct meningioma sub-regions on MRI including enhancing tumor, non-enhancing tumor core, and surrounding nonenhancing T2/FLAIR hyperintensity. Models will be evaluated on separate validation and held-out test datasets using standardized metrics utilized across the BraTS 2023 series of challenges including the Dice similarity coefficient and Hausdorff distance. The models developed during the course of this challenge will aid in incorporation of automated meningioma MRI segmentation into clinical practice, which will ultimately improve care of patients with meningioma.

The role of adjuvant chemotherapy in the management of acute promyelocytic leukemia differentiation syndrome

Acute Promyelocytic Leukemia (APL) is characterized by the t(15;17) chromosomal translocation resulting in a PML-RARA fusion protein. The all-trans-retinoic acid (ATRA) and Arsenic Trioxide (ATO) only regimens have demonstrated success in treating low- and intermediate-risk patients. However, induction with ATRA/ATO only regimens have been showing increased incidence of differentiation syndrome (DS), a potentially lethal complication, traditionally treated with dexamethasone. We conducted a three-institution retrospective study, aiming to evaluate the role of short-term adjuvant chemotherapy in managing moderate DS for patients with low- or intermediate-risk APL initially treated with ATRA/ATO only protocols. We evaluated the difference in incidence and duration of moderate DS in APL patients who were treated with ATRA/ATO with or without adjuvant chemotherapy. 57 low- or intermediate-risk APL patients were retrospectively identified and included for this study; 36 patients received ATRA/ATO only induction treatment, and 21 patients received ATRA/ATO/adjuvant chemotherapy combination induction therapy. Similar proportions of patients experienced DS in both groups (66.7% vs. 81.0%, P = 0.246). The median duration of DS resolution in patients receiving ATRA/ATO only was 17 days (n = 23), and in patients receiving combination therapy was 8 days (n = 16) (P = 0.0001). The lengths of hospital stay in patients receiving ATRO/ATO only was 38 days (n = 7), and in patients receiving combination therapy was 14 days (n = 17) (P = 0.0007). In conclusion, adding adjuvant chemotherapy to ATRA/ATO only protocol may reduce the duration of DS and the length of hospital stay during APL induction treatment.

Is There a Role for Prone Computed Tomography Prior to Percutaneous Nephrolithotomy?

BACKGROUND

The majority of PCNLs are performed prone, while most pre-operative CT scans are done supine. The purpose of this pilot study is to determine if there is utility of prone CT scans in pre-operative planning for prone PCNL by identifying patient populations at risk for organ injury and tract length related complications.

MATERIALS AND METHODS

To represent typical pre-operative planning using CT, 2D-axial-prone/supine percutaneous tract measurements were performed by minimizing the distance from the target calyx to the posterior-lateral skin in a single axial plane. The minimum distance and organ interception rates for the 2D-axial planning scans were recorded.

RESULTS

A total of 60 CT Colonography and 13 CT Urography patients were included in analysis. There were 42 females and 31 males with unspecified pathologies ranging in age from 27 to 86 years and in BMI from 17.1 to 49. Multiple logistic regression identified female gender and low BMI as predictors of organ interception on the left. On multiple linear regression comparing the difference in axial prone/supine lengths; BMI, gender, and age were not significant independent predictors of changes in tract length in any pole when prone versus supine. However, shorter supine tracts tended to lengthen when prone, and longer supine tracts tended to shorten.

CONCLUSIONS

This pilot study has demonstrated that patients with very long and short estimates of tract length in the supine position may have shorter and longer tracts, respectively, with repositioning to prone. Thus, prone CT may have benefit when anticipating exceptionally long (>15cm) tract lengths. Prone scans also revealed more potential organ interceptions, particularly for low BMI and females in the left upper pole. In patients for whom prone CT demonstrates an organ interception, the urologist should consider an alternate target calyx or ultrasound guided percutaneous access to identify the most appropriate needle trajectory.