Imaging of GBM in the Age of Molecular Markers and MRI Guided Adaptive Radiation Therapy.

Glioblastoma (GBM) continues to be one of the most lethal malignancies and is almost always fatal. In this review article, the role of radiation therapy, systemic therapy, as well as the molecular basis of classifying GBM is described. Technological advances in the treatment of GBM are outlined as well as the diagnostic imaging characteristics of this tumor. In addition, factors that affect prognosis such as differentiating progression from treatment effect is discussed. The role of MRI guided radiation therapy and how this technology may provide a mechanism to improve the care of patients with this disease are described.

Trends in Publication Speed of Radiation Oncology Research from 2010 to 2019.

PURPOSE: In this investigation, we aimed to describe trends in time to acceptance (TTA) and time to online publication (TTOP) of research published in leading radiation oncology journals from 2010 to 2019. We further sought to identify journal characteristics that might influence TTA and TTOP. METHODS AND MATERIALS: We searched the publication history of 5 leading international radiation oncology journals. For all research articles accepted from January 1, 2010, to December 31, 2019, we tabulated the date of article receipt, the date of acceptance, and the date of online publication when available. The TTA was calculated as the number of elapsed days from article receipt to acceptance, and the TTOP was calculated as the number of elapsed days from article acceptance to online publication. Using the Mann-Kendall test, we assessed for monotonic trends over time and used the post hoc Theil-Sen method to estimate rates of change. We created a multiple regression model to identify journal characteristics associated with TTA and TTOP. RESULTS: In total, 10,132 articles were included. Both the TTA and the TTOP decreased significantly from 2010 to 2019 (P = .005 and P < .001, respectively), with an estimated decrease of 1.5 days per year for the TTA and 7.0 days per year for the TTOP. Multiple regression modeling revealed that a higher journal impact factor was independently associated with an increased TTA (P < .001) and a decreased TTOP (P < .001). A higher number of accepted journal articles per year was associated with a decreased TTA (P < .001) and an increased TTOP (P < .001). CONCLUSIONS: Radiation oncology research has been accepted and published online at increasingly faster rates during the past decade. The TTA may be longer in higher-impact, more selective journals, possibly suggesting a need for comprehensive peer review and complex editorial decisions. However, these articles are also published online faster after article acceptance. Future work examining patterns of acceptance and publication speed is needed to encourage rapid dissemination of practice-guiding data.

Treatment Strategies for Oligometastatic Breast Cancer.

OPINION STATEMENT: Oligometastatic breast cancer, typically defined as the presence of 1-5 metastases, represents an intermediate state between locally advanced and widely metastatic disease. Emerging research suggests that oligometastatic cancer has a unique molecular signature distinct from widely metastatic disease, and that it carries a superior prognosis. Owing to its more limited capacity for widespread progression, oligometastatic disease may benefit from aggressive ablative therapy to known metastases. Options for ablation include surgical excision, radiofrequency ablation, and hypofractionated image-guided radiotherapy (HIGRT). The phase II SABR-COMET trial, which enrolled patients with oligometastatic disease of multiple histologies and randomized them to HIGRT vs. standard of care, found a notable survival advantage in favor of HIGRT. Other data suggest that HIGRT may synergize with immunotherapy by releasing powerful cytokines that increase anti-tumor immune surveillance and by recruiting tumor infiltrating lymphocytes, helping to overcome resistance to therapy. There are many ongoing trials exploring the role of ablative therapy, most notably HIGRT, with or without immunotherapy, for the treatment of oligometastatic breast cancer.We believe that patients with oligometastatic breast cancer should be offered enrollment on prospective clinical trials when possible. Outside the context of a clinical trial, we recommend that select patients with oligometastatic breast cancer be offered treatment with a curative approach, including ablative therapy to all sites of disease if it can be safely accomplished. Currently, selection criteria to consider for ablative therapy include longer disease-free interval from diagnosis to metastasis (>2 years), fewer metastases, and fewer involved organs. Undoubtedly, new data will refine or even upend our understanding of the definition and optimal management of oligometastatic disease.

Single Fraction Radiation for Myeloid Sarcoma Is as Effective as Multi-Fraction Regimens for Tumor Regression and Control.

INTRODUCTION/BACKGROUND: Myeloid sarcoma is a rare extramedullary manifestation of immature myeloid/monocyte cells. Radiotherapy (RT) yields good local control, but data on different fractionation schemes are limited. The goal of this retrospective study was to share our institutional experience and assess volumetric regression with differential fractionation. MATERIALS AND METHODS: We evaluated patients treated for myeloid sarcoma between 2000 and 2019 and categorized them into Group A (treated with RT) and Group B (no RT). We assessed local control using cumulative incidence function analysis. Post-treatment imaging sequences were analyzed for volumetric calculations. RESULTS: Forty-four patients with 80 lesions were assessed. Twenty-three patients with 52 lesions received RT (Group A), and 6 lesions received a single fraction of RT. There were 2 instances of local progression in Group A and 8 in Group B, with a cumulative incidence function estimate of local progression in Group A of 2.4% at 1 year and 6.9% at 2 years, significantly reduced compared to 29.7% and 35.5% in Group B, respectively (hazard ratio 0.13 [95% confidence interval 0.030.63], P = .011). No lesion treated with a single fraction of RT developed local progression. Volumetric analysis for 19 chronologically followed lesions (including 3 treated with a single fraction) revealed no difference in regression between single or multi-fraction treatment. CONCLUSION: RT for myeloid sarcoma yields excellent local control and may be as effective in a single fraction as more protracted courses, though this requires validation. For a diagnosis associated with poor survival, a single palliative fraction may be optimal with potential for higher utilization.

Survival in Patients With Brain Metastases: Summary Report on the Updated Diagnosis-Specific Graded Prognostic Assessment and Definition of the Eligibility Quotient.

PURPOSE: Conventional wisdom has rendered patients with brain metastases ineligible for clinical trials for fear that poor survival could mask the benefit of otherwise promising treatments. Our group previously published the diagnosis-specific Graded Prognostic Assessment (GPA). Updates with larger contemporary cohorts using molecular markers and newly identified prognostic factors have been published. The purposes of this work are to present all the updated indices in a single report to guide treatment choice, stratify research, and define an eligibility quotient to expand eligibility. METHODS: A multi-institutional database of 6,984 patients with newly diagnosed brain metastases underwent multivariable analyses of prognostic factors and treatments associated with survival for each primary site. Significant factors were used to define the updated GPA. GPAs of 4.0 and 0.0 correlate with the best and worst prognoses, respectively. RESULTS: Significant prognostic factors varied by diagnosis and new prognostic factors were identified. Those factors were incorporated into the updated GPA with robust separation (P < .01) between subgroups. Survival has improved, but varies widely by GPA for patients with non-small-cell lung, breast, melanoma, GI, and renal cancer with brain metastases from 7-47 months, 3-36 months, 5-34 months, 3-17 months, and 4-35 months, respectively. CONCLUSION: Median survival varies widely and our ability to estimate survival for patients with brain metastases has improved. The updated GPA (available free at brainmetgpa.com) provides an accurate tool with which to estimate survival, individualize treatment, and stratify clinical trials. Instead of excluding patients with brain metastases, enrollment should be encouraged and those trials should be stratified by the GPA to ensure those trials make appropriate comparisons. Furthermore, we recommend the expansion of eligibility to allow for the enrollment of patients with previously treated brain metastases who have a 50% or greater probability of an additional year of survival (eligibility quotient > 0.50).

Beyond an Updated Graded Prognostic Assessment (Breast GPA): A Prognostic Index and Trends in Treatment and Survival in Breast Cancer Brain Metastases From 1985 to Today.

PURPOSE: Brain metastases are a common sequelae of breast cancer. Survival varies widely based on diagnosis-specific prognostic factors (PF). We previously published a prognostic index (Graded Prognostic Assessment [GPA]) for patients with breast cancer with brain metastases (BCBM), based on cohort A (1985-2007, n = 642), then updated it, reporting the effect of tumor subtype in cohort B (1993-2010, n = 400). The purpose of this study is to update the Breast GPA with a larger contemporary cohort (C) and compare treatment and survival across the 3 cohorts. METHODS AND MATERIALS: A multi-institutional (19), multinational (3), retrospective database of 2473 patients with breast cancer with newly diagnosed brain metastases (BCBM) diagnosed from January 1, 2006, to December 31, 2017, was created and compared with prior cohorts. Associations of PF and treatment with survival were analyzed. Kaplan-Meier survival estimates were compared with log-rank tests. PF were weighted and the Breast GPA was updated such that a GPA of 0 and 4.0 correlate with the worst and best prognoses, respectively. RESULTS: Median survival (MS) for cohorts A, B, and C improved over time (from 11, to 14 to 16 months, respectively; P < .01), despite the subtype distribution becoming less favorable. PF significant for survival were tumor subtype, Karnofsky Performance Status, age, number of BCBMs, and extracranial metastases (all P < .01). MS for GPA 0 to 1.0, 1.5-2.0, 2.5-3.0, and 3.5-4.0 was 6, 13, 24, and 36 months, respectively. Between cohorts B and C, the proportion of human epidermal receptor 2 + subtype decreased from 31% to 18% (P < .01) and MS in this subtype increased from 18 to 25 months (P < .01). CONCLUSIONS: MS has improved modestly but varies widely by diagnosis-specific PF. New PF are identified and incorporated into an updated Breast GPA (free online calculator available at brainmetgpa.com). The Breast GPA facilitates clinical decision-making and will be useful for stratification of future clinical trials. Furthermore, these data suggest human epidermal receptor 2-targeted therapies improve clinical outcomes in some patients with BCBM.

Estrogen/progesterone receptor and HER2 discordance between primary tumor and brain metastases in breast cancer and its effect on treatment and survival.

BACKGROUND: Breast cancer treatment is based on estrogen receptors (ERs), progesterone receptors (PRs), and human epidermal growth factor receptor 2 (HER2). At the time of metastasis, receptor status can be discordant from that at initial diagnosis. The purpose of this study was to determine the incidence of discordance and its effect on survival and subsequent treatment in patients with breast cancer brain metastases (BCBM). METHODS: A retrospective database of 316 patients who underwent craniotomy for BCBM between 2006 and 2017 was created. Discordance was considered present if the ER, PR, or HER2 status differed between the primary tumor and the BCBM. RESULTS: The overall receptor discordance rate was 132/316 (42%), and the subtype discordance rate was 100/316 (32%). Hormone receptors (HR, either ER or PR) were gained in 40/160 (25%) patients with HR-negative primary tumors. HER2 was gained in 22/173 (13%) patients with HER2-negative primary tumors. Subsequent treatment was not adjusted for most patients who gained receptors-nonetheless, median survival (MS) improved but did not reach statistical significance (HR, 17-28 mo, P = 0.12; HER2, 15-19 mo, P = 0.39). MS for patients who lost receptors was worse (HR, 27-18 mo, P = 0.02; HER2, 30-18 mo, P = 0.08). CONCLUSIONS: Receptor discordance between primary tumor and BCBM is common, adversely affects survival if receptors are lost, and represents a missed opportunity for use of effective treatments if receptors are gained. Receptor analysis of BCBM is indicated when clinically appropriate. Treatment should be adjusted accordingly. KEY POINTS: 1. Receptor discordance alters subtype in 32% of BCBM patients.2. The frequency of receptor gain for HR and HER2 was 25% and 13%, respectively.3. If receptors are lost, survival suffers. If receptors are gained, consider targeted treatment.

What is the role of radiotherapy for extensive-stage small cell lung cancer in the immunotherapy era?

Small cell lung cancer has been a difficult disease to treat with poor survival and few significant improvements in outcomes in the last three decades. Most recently the addition of atezolizumab to chemotherapy in the first-line treatment of extensive-stage small cell lung cancer (ES-SCLC) resulted in improved overall survival and progression-free survival compared to chemotherapy alone. Recent randomized studies examining both consolidative thoracic radiotherapy and prophylactic cranial irradiation (PCI) in ES-SCLC have impacted the utilization of these interventions. The approval of immune checkpoint inhibitors (ICIs) to platinum/etoposide chemotherapy for the treatment of ES-SCLC in the front-line setting may also further impact the role of radiotherapy in this disease. In this article, we review the current evidence supporting thoracic radiotherapy in ES-SCLC and discuss the promising therapeutic implications of thoracic radiation in light of the inclusion of ICIs. We also address how the increasing routine use of surveillance brain magnetic resonance imaging (MRI) and ICIs may diminish the use of PCI in ES-SCLC.

Cerebral blood volume mapping with ferumoxytol in dynamic susceptibility contrast perfusion MRI: Comparison to standard of care.

BACKGROUND: Cerebral blood volume (CBV) mapping with a dynamic susceptibility contrast (DSC) perfusion technique has become a clinical tool in diagnosing and follow-up of brain tumors. Ferumoxytol, a long-circulating iron oxide nanoparticle, has been tested for CBV mapping, but the optimal dose has not been established. PURPOSE: To compare ferumoxytol DSC of two different doses to standard of care gadoteridol by analyzing time-intensity curves and CBV maps in normal-appearing brain regions. STUDY TYPE: Retrospective. SUBJECTS: Fifty-four patients with various brain disorders. FIELD STRENGTH/SEQUENCE: 3T MRI. DSC-MRI was performed with 0.1 mmol/kg gadoteridol and 1 day later with ferumoxytol in doses of 1 or 2 mg/kg. ASSESSMENT: Signal changes during first pass, relative CBV (rCBV) in normal-appearing thalamus, putamen, and globus pallidus, and contrast-to-noise ratio (CNR) of the CBV maps were compared between gadoteridol and various doses of ferumoxytol using an automated method. To subjectively assess the quality of the CBV maps, two blinded readers also assessed visual conspicuity of the putamen. STATISTICAL TESTS: Linear mixed effect model was used for statistical comparison. RESULTS: Compared to gadoteridol, 1 mg/kg ferumoxytol showed no difference in CNR (P = 0.6505), peak ΔR2*, and rCBV in the putamen (P = 0.2669, 0.0871) or in the thalamus (P = 0.517, 0.9787); 2 mg/kg ferumoxytol increased peak ΔR2* as well as the CNR (P < 0.0001), but also mildly increased rCBV in putamen and globus pallidus (P = 0.0005, 0.0012). Signal intensities during first pass remained highly above the noise level, with overlapping of 95% confidence intervals with noise only in 3 out of 162 tested regions. Compared to gadoteridol, the visual image quality showed mild improvement with 1 mg/kg (P = 0.02) and marked improvement with 2 mg/kg ferumoxytol (P < 0.0001). DATA CONCLUSION: 1 mg/kg ferumoxytol provides similar imaging results to standard gadoteridol for DSC-MRI, and 2 mg/kg has a benefit of increased CNR, but may also result in mildly increased rCBV values. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2018;48:441-448.

Development of a nomogram to predict the clinical impact of a postexcision preirradiation mammogram.

We aimed to better quantify the impact of a postexcision preirradiation mammogram (PPM), first by identifying factors associated with abnormal results and then incorporating these findings into a nomogram. Beginning February 2011, our institution made a practice change to obtain a PPM on all patients with any calcifications identified. A total of 530 patients underwent a PPM. Suspicious abnormalities were reported in 61 patients (11.5%), with the PPM leading to a change in management in 47 instances (8.9%). A nomogram was created based on patient and tumor characteristics to identify patients most likely to have an abnormal PPM.

High-resolution steady-state cerebral blood volume maps in patients with central nervous system neoplasms using ferumoxytol, a superparamagnetic iron oxide nanoparticle.

Cerebral blood volume (CBV) measurement complements conventional magnetic resonance imaging (MRI) to indicate pathologies in the central nervous system (CNS). Dynamic susceptibility contrast (DSC) perfusion imaging is limited by low resolution and distortion. Steady-state (SS) imaging may provide higher resolution CBV maps but was not previously possible in patients. We tested the feasibility of clinical SS-CBV measurement using ferumoxytol, a nanoparticle blood pool contrast agent. SS-CBV measurement was analyzed at various ferumoxytol doses and compared with DSC-CBV using gadoteridol. Ninety nine two-day MRI studies were acquired in 65 patients with CNS pathologies. The SS-CBV maps showed improved contrast to noise ratios, decreased motion artifacts at increasing ferumoxytol doses. Relative CBV (rCBV) values obtained in the thalamus and tumor regions indicated good consistency between the DSC and SS techniques when the higher dose (510 mg) ferumoxytol was used. The SS-CBV maps are feasible using ferumoxytol in a clinical dose of 510 mg, providing higher resolution images with comparable rCBV values to the DSC technique. Physiologic imaging using nanoparticles will be beneficial in visualizing CNS pathologies with high vascularity that may or may not correspond with blood-brain barrier abnormalities.

Integrated cone-beam CT and fluoroscopic navigation in treatment of head and neck vascular malformations and tumors.

BACKGROUND AND AIM: Accurate direct puncture access to vascular malformations and tumors of the head and neck is critical to successful embolization treatment and avoidance of complications. The primary focus of this project was to evaluate the accuracy and ease of needle placement using integrated 3D cone-beam CT and fluoroscopic guidance in accessing head and neck vascular malformations and tumors, and to determine its contribution to lesion treatment. METHODS: A total of 27 patients, 14 female and 13 male, aged 4-63 years, were included in this study. The lesions included 11 venous malformations, 5 arteriovenous malformations, 5 juvenile nasopharyngeal angiofibromas, 2 lymphovenous malformations, 1 lymphatic malformation, 1 capillary malformation, 1 nasal cavity leiomyoma, and 1 dural arteriovenous fistula. A total of 65 needle placements in 33 procedures were performed using an integrated 3D cone-beam CT and fluoroscopic guidance system. RESULTS: Targeting was successful with a single pass in 62 of 65 planned needle placements to a superficial location in 24, the hypopharynx, retro-pharyngeal, pyriform sinus, or paratracheal spaces in 21, the sphenoid sinus and upper nasal cavity via trans-nasal approach in 5, intra-orbital in 5, intra-laryngeal in 4, pterygo-palatine fossa in 4, external auditory canal in 1, and intracranial via a juxta-torcular burr hole in 1. Needle placement was within 2 mm of the planned target in 11 locations in the 8 patients where post needle-placement cone-beam CT was obtained. CONCLUSION: This integrated 3D cone-beam CT and fluoroscopic guidance allowed access to deep, difficult to access, locations with ease using a single needle pass in most cases, resulting in improved treatment with decreased procedure times.

Comparative analysis of ferumoxytol and gadoteridol enhancement using T1- and T2-weighted MRI in neuroimaging.

OBJECTIVE: Ferumoxytol, an ultrasmall superparamagnetic iron oxide particle, has been suggested as a potential alternative MRI contrast agent in patients with renal failure. We compared ferumoxytol to gadoteridol enhancement on T1- and T2-weighted MRI in CNS disorders to explore its diagnostic utility. SUBJECTS AND METHODS: Data were collected from three protocols in 70 adults who underwent alternate-day gadoteridol- and ferumoxytol-enhanced MRI using identical parameters. Two neuroradiologists measured lesion-enhancing size and intensity on contrast-enhanced T1-weighted images in consensus. T2-weighted images were evaluated for the presence of contrast-enhanced hypointensity. Mixed model repeated measures analysis of variance determined differences between T1-weighted enhancement size and intensity for individual protocols and group. RESULTS: After exclusions, 49 MRI studies in 29 men and 20 women (mean age, 51 years) were assessed. T1-weighted estimated enhancing sizes were different between agents (p = 0.0456) as a group; however, no differences were observed with untreated gliomas (n = 17) in two protocols (p = 1.0 and p = 0.99, respectively). Differences in T1-weighted enhancement intensity between agents were significant for the group overall (p = 0.0006); however, three-way interactions were not significant (p = 0.1233). T2-weighted images were assessed for contrast-enhanced hypointensity, observed in 26 of 49 (53%) ferumoxytol and zero of 49 (0%) gadoteridol scans. CONCLUSION: Ferumoxytol may be a useful MRI contrast agent in patients who are unable to receive gadolinium-based contrast agents. Greater experience with a wider variety of disorders is necessary to understand differences in enhancement with ferumoxytol compared with gadolinium-based contrast agents, given their different mechanisms of action.