Stereotactic radiosurgery for treatment of radiation-induced meningiomas: a multiinstitutional study

OBJECTIVE

Radiation-induced meningiomas (RIMs) are associated with aggressive clinical behavior. Stereotactic radiosurgery (SRS) is sometimes considered for selected RIMs. The authors investigated the effectiveness and safety of SRS for the management of RIMs.

METHODS

From 12 institutions participating in the International Radiosurgery Research Foundation, the authors pooled patients who had prior cranial irradiation and were subsequently clinically diagnosed with WHO grade I meningiomas that were managed with SRS.

RESULTS

Fifty-two patients underwent 60 SRS procedures for histologically confirmed or radiologically suspected WHO grade I RIMs. The median ages at initial cranial radiation therapy and SRS for RIM were 5.5 years and 39 years, respectively. The most common reasons for cranial radiation therapy were leukemia (21%) and medulloblastoma (17%). There were 39 multiple RIMs (35%), the mean target volume was 8.61 ± 7.80 cm3, and the median prescription dose was 14 Gy. The median imaging follow-up duration was 48 months (range 4-195 months). RIM progressed in 9 patients (17%) at a median duration of 30 months (range 3-45 months) after SRS. Progression-free survival at 5 years post-SRS was 83%. Treatment volume ≥ 5 cm3 predicted progression (HR 8.226, 95% CI 1.028-65.857, p = 0.047). Seven patients (14%) developed new neurological symptoms or experienced SRS-related complications or T2 signal change from 1 to 72 months after SRS.

CONCLUSIONS

SRS is associated with durable local control of RIMs in the majority of patients and has an acceptable safety profile. SRS can be considered for patients and tumors that are deemed suboptimal, poor surgical candidates, and those whose tumor again progresses after removal.

Stereotactic radiosurgery with versus without prior Onyx embolization for brain arteriovenous malformations

OBJECTIVE

Investigations of the combined effects of neoadjuvant Onyx embolization and stereotactic radiosurgery (SRS) on brain arteriovenous malformations (AVMs) have not accounted for initial angioarchitectural features prior to neuroendovascular intervention. The aim of this retrospective, multicenter matched cohort study is to compare the outcomes of SRS with versus without upfront Onyx embolization for AVMs using de novo characteristics of the preembolized nidus.

METHODS

The International Radiosurgery Research Foundation AVM databases from 1987 to 2018 were retrospectively reviewed. Patients were categorized based on AVM treatment approach into Onyx embolization (OE) and SRS (OE+SRS) or SRS alone (SRS-only) cohorts and then propensity score matched in a 1:1 ratio. The primary outcome was AVM obliteration. Secondary outcomes were post-SRS hemorrhage, all-cause mortality, radiological and symptomatic radiation-induced changes (RICs), and cyst formation. Comparisons were analyzed using crude rates and cumulative probabilities adjusted for competing risk of death.

RESULTS

The matched OE+SRS and SRS-only cohorts each comprised 53 patients. Crude rates (37.7% vs 47.2% for the OE+SRS vs SRS-only cohorts, respectively; OR 0.679, p = 0.327) and cumulative probabilities at 3, 4, 5, and 6 years (33.7%, 44.1%, 57.5%, and 65.7% for the OE+SRS cohort vs 34.8%, 45.5%, 59.0%, and 67.1% for the SRS-only cohort, respectively; subhazard ratio 0.961, p = 0.896) of AVM obliteration were similar between the matched cohorts. The secondary outcomes of the matched cohorts were also similar. Asymptomatic and symptomatic embolization-related complication rates in the matched OE+SRS cohort were 18.9% and 9.4%, respectively.

CONCLUSIONS

Pre-SRS AVM embolization with Onyx does not appear to negatively influence outcomes after SRS. These analyses, based on de novo nidal characteristics, thereby refute previous studies that found detrimental effects of Onyx embolization on SRS-induced AVM obliteration. However, given the risks incurred by nidal embolization using Onyx, this neoadjuvant intervention should be used judiciously in multimodal treatment strategies involving SRS for appropriately selected large-volume or angioarchitecturally high-risk AVMs.

Nanoparticles for Stem Cell Therapy Bioengineering in Glioma

Gliomas are a dismal disease associated with poor survival and high morbidity. Current standard treatments have reached a therapeutic plateau even after combining maximal safe resection, radiation, and chemotherapy. In this setting, stem cells (SCs) have risen as a promising therapeutic armamentarium, given their intrinsic tumor homing as well as their natural or bioengineered antitumor properties. The interplay between stem cells and other therapeutic approaches such as nanoparticles holds the potential to synergize the advantages from the combined therapeutic strategies. Nanoparticles represent a broad spectrum of synthetic and natural biomaterials that have been proven effective in expanding diagnostic and therapeutic efforts, either used alone or in combination with immune, genetic, or cellular therapies. Stem cells have been bioengineered using these biomaterials to enhance their natural properties as well as to act as their vehicle when anticancer nanoparticles need to be delivered into the tumor microenvironment in a very precise manner. Here, we describe the recent developments of this new paradigm in the treatment of malignant gliomas.

Estimating the Number of Patients Eligible for Carbon Ion Radiotherapy in the United States

Purpose

Carbon ion radiotherapy (CIRT) is an emerging radiotherapy modality with potential advantages over conventional photon-based therapy, including exhibiting a Bragg peak and greater relative biological effectiveness, leading to a higher degree of cell kill. Currently, 13 centers are treating with CIRT, although there are no centers in the United States. We aimed to estimate the number of patients eligible for a CIRT center in the United States.

Materials and Methods

Using the National Cancer Database, we analyzed the incidence of cancers frequently treated with CIRT internationally (glioblastoma, hepatocellular carcinoma, cholangiocarcinoma, locally advanced pancreatic cancer, non-small cell lung cancer, localized prostate cancer, soft tissue sarcomas, and specific head and neck cancers) diagnosed in the United States in 2015. The percentage and number of patients likely benefiting from CIRT was estimated with inclusion criteria from clinical trials and retrospective studies, and that ratio was applied to 2019 cancer statistics. An adaption correction rate was applied to estimate the potential number of patients treated with CIRT. Given the high dependency on prostate and lung cancers and the uncertain adoption of CIRT in those diseases, the data were then reanalyzed excluding those diagnoses.

Results

Of the 1 127 455 new cases of cancer diagnosed in the United States in 2015, there were 213 073 patients (18.9%) eligible for treatment with CIRT based on inclusion criteria. When applying this rate and the adaption correction rate to the 2019 incidence data, an estimated 89 946 patients (42.2% of those fitting inclusion criteria) are eligible for CIRT. Excluding prostate and lung cancers, there were an estimated 8922 patients (10% of those eligible for CIRT) eligible for CIRT. The number of patients eligible for CIRT is estimated to increase by 25% to 27.7% by 2025.

Conclusion

Our analysis suggests a need for CIRT in the United States in 2019, with the number of patients possibly eligible to receive CIRT expected to increase during the coming 5 to 10 years.

Trends in Cancer Incidence in US Adolescents and Young Adults, 1973-2015

IMPORTANCE

Previous studies have demonstrated that adolescents and young adults (AYAs) with cancer are a distinct cancer population; however, research on long-term epidemiological trends and characteristics of cancers in AYAs is lacking.

OBJECTIVE

To characterize the epidemiology of cancer in AYAs aged 15 to 39 years with respect to (1) patient demographic characteristics, (2) frequencies of cancer types, and (3) cancer incidence trends over time.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, serial cross-sectional, population-based study used registry data from the Surveillance, Epidemiology, and End Results (SEER) database from January 1, 1973, to December 31, 2015 (SEER 9 and SEER 18). The study population was from geographically distinct US regions, chosen to represent the racial and ethnic heterogeneity of the country. Initial analyses were performed from January 1 to August 31, 2019.

MAIN OUTCOMES AND MEASURES

Incidence rates and descriptive epidemiological statistics for patients aged 15 to 39 years with invasive cancer.

RESULTS

A total of 497 452 AYAs diagnosed from 1973 to 2015 were included in this study, with 293 848 (59.1%) female and 397 295 (79.9%) White participants. As AYAs aged, an increase in the relative incidence of carcinomas and decrease in the relative incidence of leukemias, lymphomas, germ cell and trophoblastic neoplasms, and neoplasms of the central nervous system occurred. Among the female AYAs, 72 564 (24.7%) were diagnosed with breast carcinoma; 48 865 (16.6%), thyroid carcinoma; and 33 828 (11.5%), cervix and uterus carcinoma. Among the male AYAs, 37 597 (18.5%) were diagnosed with testicular cancer; 20 850 (10.2%), melanoma; and 19 532 (9.6%), non-Hodgkin lymphoma. The rate of cancer in AYAs increased by 29.6% from 1973 to 2015, with a mean annual percentage change (APC) per 100 000 persons of 0.537 (95% CI, 0.426-0.648; P < .001). Kidney carcinoma increased at the greatest rate for both male (APC, 3.572; 95% CI, 3.049-4.097; P < .001) and female (APC, 3.632; 95% CI, 3.105-4.162; P < .001) AYAs.

CONCLUSIONS AND RELEVANCE

In this cross-sectional, US population-based study, cancer in AYAs was shown to have a unique epidemiological pattern and is a growing health concern, with many cancer subtypes having increased in incidence from 1973 to 2015. Continued research on AYA cancers is important to understanding and addressing the distinct health concerns of this population.

RADT-17. RADIOTHERAPY IN THE MANAGEMENT OF OPTIC NERVE SHEATH MENINGIOMAS: AN INTERNATIONAL SYSTEMATIC REVIEW AND META-ANALYSIS OF EIGHTEEN STUDIES

INTRODUCTION

Optic nerve sheath meningiomas (ONSMs) are often managed with radiotherapy (RT) with the goal of achieving radiographic local control (LC) to prevent further decline in visual acuity (VA); however, reports on outcomes are limited to small retrospective series. Thus, we aimed to perform a systematic review and meta-analysis of outcomes for patients with ONSM treated with RT.

METHODS

A PICOS/PRISMA/MOOSE selection criteria was utilized to identify studies for inclusion. Primary outcomes were stable or improved VA and radiographic LC at last follow-up. The secondary outcome was incidence of radiation-induced retinopathy. Weighted random effects meta-analyses using the DerSimonian and Laird methods were conducted to characterize effect sizes. Mixed effects regression models were used to examine potential correlations between gross tumor volume (GTV) and outcomes.

RESULTS

In total, 381 patients with ONSM across 18 published studies were included. Of these, 332 and 386 treated ONSMs had information on VA or LC, respectively. Median age was 46.75 (range: 9-87), median/mean GTV was 2.905cc (range: 0.28-26.3), and median follow-up was 51.15 months (range: 1-248.4 months). The estimated LC rate at last follow-up was 100% (95% CI: 98-100%), and the estimated proportion of patients with stable or improved VA at last follow-up was 89% (95% CI: 84-93%). The rate of chronic radiation retinopathy was estimated to be 7% (95% CI: 5-11%). GTV was significantly associated with VA (p=0.014) with estimated VA rates of 96.4%, 91.4%, and 80.5% for GTVs of 2.0, 3.0, and 4.0ccs, respectively.

CONCLUSIONS

RT was well-tolerated in the treatment of ONSM with excellent LC achieved. Nearly 90% of patients noted either stability or improvement in VA. Larger ONSMs were found to be associated with poorer VA. Incidences of radiation-induced retinopathy were limited and estimated to be less than 10%.

Quantitation and predictors of short-term mortality following extrapleural pneumonectomy, pleurectomy/decortication, and nonoperative management for malignant pleural mesothelioma

Background

For malignant pleural mesothelioma (MPM), the benefit of resection, as well as the optimal surgical technique, remain controversial. In efforts to better refine patient selection, this retrospective observational cohort study queried the National Cancer Database in an effort to quantify and evaluate predictors of 30- and 90-day mortality between extrapleural pneumonectomy (EPP) and pleurectomy/decortication (P/D), as well as nonoperative management.

Methods

After applying selection criteria, cumulative incidences of mortality by treatment paradigm were graphed for the unadjusted and propensity-matched populations, as well as for six a priori age-based intervals (≤60, 61–65, 66–70, 71–75, 76–80, and ≥81 years). The interaction between age and hazard ratio (HR) for mortality between treatment paradigms was also graphed. Cox multivariable analysis ascertained factors independently associated with 30- and 90-day mortality.

Results

Of 10,723 patients, 2,125 (19.8%) received resection (n=438 EPP, n=1,687 P/D) and 8,598 (80.2%) underwent nonoperative management. The unadjusted 30/90-day mortality for EPP, P/D, and all operated cases was 3.0%/8.0%, 5.4%/14.1%, and 4.9%/12.8%, respectively. There were no short-term mortality differences between EPP and P/D following propensity-matching, within each age interval, or between age subgroups on interaction testing (P>0.05 for all). Nonoperative patients had a crude 30- and 90-day mortality of 9.9% and 24.6%, respectively. Several variables were identified as predictors of short-term mortality, notably patient age (HR 1.022, P<0.001), Charlson-Deyo comorbidity index (HR 1.882, P<0.001), receipt of treatment at high-volume centers (HR 0.834, P=0.032) and induction chemotherapy (HR 1.735, P=0.025), among others. The patient (yearly) incremental increase in age conferred 2.0% (30 day) and 2.2% (90 day) increased risk of mortality (P<0.001).

Conclusions

Quantitative estimates of age-associated 30- and 90-day mortality of EPP and P/D should be considered when potentially operable patients are counseled regarding the risks and benefits of resection.

Engineering Three-Dimensional Tumor Models to Study Glioma Cancer Stem Cells and Tumor Microenvironment

Glioblastoma (GBM) is the most common and devastating primary brain tumor, leading to a uniform fatality after diagnosis. A major difficulty in eradicating GBM is the presence of microscopic residual infiltrating disease remaining after multimodality treatment. Glioma cancer stem cells (CSCs) have been pinpointed as the treatment-resistant tumor component that seeds ultimate tumor progression. Despite the key role of CSCs, the ideal preclinical model to study the genetic and epigenetic landmarks driving their malignant behavior while simulating an accurate interaction with the tumor microenvironment (TME) is still missing. The introduction of three-dimensional (3D) tumor platforms, such as organoids and 3D bioprinting, has allowed for a better representation of the pathophysiologic interactions between glioma CSCs and the TME. Thus, these technologies have enabled a more detailed study of glioma biology, tumor angiogenesis, treatment resistance, and even performing high-throughput screening assays of drug susceptibility. First, we will review the foundation of glioma biology and biomechanics of the TME, and then the most up-to-date insights about the applicability of these new tools in malignant glioma research.

Intraventricular choroid plexus tumors: clinical characteristics and impact of current management on survival

INTRODUCTION

Choroid plexus tumors (CPTs) represent one of the most common intraventricular tumors. Although most are benign, they often reach considerable sizes before clinical manifestation, challenging their surgical management. We aim to describe the clinical characteristics and the impact of current management on the survival of patients harboring intraventricular CPT.

METHODS

The National Cancer Database (NCDB) was queried to identify biopsy-proven intraventricular CPT patients (2004-2015). Demographic and patterns of care were described, the log-rank method was used to independently analyze survival according to age, WHO grade and extent of resection (EOR). Multivariate analysis was performed to investigate the impact of prognostic factors on overall survival (OS).

RESULTS

A total of 439 CPT patients with known WHO grade were included. WHO grade I tumors were more frequent in adults, while WHO grade III tumors were more common in pediatric population. Most CPTs were benign, with a median tumor size of 3-4 cm. Mean tumor size in pediatric population was greater than in adult population (4.39 cm vs. 2.7 cm; p < 0.01). Frequency was similar between males and females (51.7% vs. 48.3%; p > 0.0.5). Five- and ten-year OS among all patients was 87% and 84%, respectively. EOR was not associated with survival for any WHO grade. On multivariable analysis, only patient age (p = 0.022), WHO grade (p = 0.003) and medical comorbidity scores (p = 0.002) were independently associated with OS after diagnosis.

CONCLUSION

Patients with CPTs present at different stages of life, with sizable tumor burden and distinct WHO grade prevalence. Considering their favorable survival, efforts to improve tumor control should be meticulously weighed against the long-term risk associated with surgery, radiation, and chemotherapy.

Radiation therapy strategies for skull-base malignancies

INTRODUCTION

The management of skull base malignancies continues to evolve with improvements in surgical technique, advances in radiation delivery and novel systemic agents.

METHODS

In this review, we aim to discuss in detail the management of common skull base pathologies which typically require multimodality therapy, focusing on the radiotherapeutic aspects of care.

RESULTS

Technological advances in the administration of radiation therapy have led to a wide variety of different treatment strategies for the treatment of skull base malignances, with outcomes summarized herein.

CONCLUSION

Radiation treatment plays a key and critical role in the management of patients with skull base tumors. Recent advancements continue to improve the risk/benefit ratio for radiotherapy in this setting.

Toxicity in combination immune checkpoint inhibitor and radiation therapy: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Immune checkpoint inhibitor with radiation therapy (ICI + RT) is under investigation for improved patient outcome, so we performed a systematic review/meta-analysis of toxicities for ICI + RT compared to immune checkpoint inhibitor (ICI) therapy alone.

MATERIALS AND METHODS

A PRISMA-compliant systematic review of studies in MEDLINE (PubMed) and in the National Comprehensive Cancer Network guidelines was conducted, with primary outcome grade 3 + toxicity. Criteria for ICI alone were: phase III/IV trials that compared immunotherapy to placebo, chemotherapy, or alternative immunotherapy; and for ICI + RT: prospective/retrospective studies with an arm treated with ICI + RT. Meta-analysis was performed by random effects models using the DerSimonian and Laird method. The I² statistic and Cochran's Q test were used to assess heterogeneity, while funnel plots and Egger's test assessed publication bias.

RESULTS

This meta-analysis included 51 studies (n = 15,398), with 35 ICI alone (n = 13,956) and 16 ICI + RT studies (n = 1,442). Our models showed comparable grade 3-4 toxicities in ICI + RT (16.3%; 95% CI, 11.1-22.3%) and ICI alone (22.3%; 95% CI, 18.1-26.9%). Stratification by timing of radiation and irradiated site showed no significant differences, but anti-CTLA-4 therapy and melanoma showed increased toxicity. The grade 5 toxicities were 1.1% and 1.9% for ICI alone and ICI + RT respectively. There was significant heterogeneity, but not publication bias.

CONCLUSIONS

The random effects model showed comparable grade 3-4 toxicity in using ICI + RT compared to ICI alone in CNS melanoma metastases, NSCLC, and prostate cancer. ICI + RT is safe for future clinical trials in these cancers.

Epidemiology of liver metastases

AIMS

The objectives of this study were to (1) characterize the epidemiology of liver metastases at the time of primary cancer diagnosis (synchronous liver metastases), (2) characterize the incidence trends of synchronous liver metastases from 2010-2015 and (3) assess survival of patients with synchronous liver metastases.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2015 was queried to obtain cases of patients with liver metastases at the time of primary cancer diagnosis. The primary cancers with an incidence rate of liver metastasis >0.1 are presented in this analysis.

RESULTS

Among 2.4 million cancer patients, 5.14 % of cancer patients presented with synchronous liver metastases. The most common primary site was breast cancers for younger women (ages 20-50), and colorectal cancers for younger men. As patients get older, a more heterogenous population of the top cancers with liver metastases emerges including esophageal, stomach, small intestine, melanoma, and bladder cancer in addition to the large proportion of lung, pancreatic, and colorectal cancers. The 1-year survival of all patients with liver metastases was 15.1 %, compared to 24.0 % in those with non-hepatic metastases. Regression analysis showed that the presence of liver metastasis was associated with reduced survival, particularly in patients with cancers of the testis, prostate, breast, and anus, and in those with melanoma.

CONCLUSIONS

The most common primary sites for patients with liver metastases varied based on age at diagnosis. Survival for patients with liver metastasis was significantly decreased as compared to patients without liver metastasis.

Repeat Radiation in the Brain: Managing Patients With Locally Recurrent Glioma

Treatment of recurrent gliomas is especially challenging, as many of these patients have previously been treated with extensive surgery, radiation, or systemic therapy. Due to this, the optimum therapy for patients with recurrent glioma is controversial, with widely variable practice patterns. In this opinion piece, a multidisciplinary panel of experts provides rationale for their treatment approach in a patient with recurrent glioma following subtotal resection with adjuvant chemoradiation for an anaplastic astrocytoma. In summary, the consensus of the panel was to recommend re-resection if possible with hypofractionated radiotherapy schedules, with re-irradiation and systemic therapy as directed by a multidisciplinary team through repeat analysis of the tumor specimen for an updated mutational burden.

Stereotactic radiosurgery for acromegaly: an international systematic review and meta-analysis of clinical outcomes

INTRODUCTION

We performed a systematic review and meta-analysis of clinical outcomes for patients with acromegaly treated with stereotactic radiosurgery (SRS).

METHODS

Primary outcomes were 5- and 10-year endocrine remission (ER) and endocrine control (EC). Secondary outcomes were 10-year radiographic local control (LC), visual toxicity, and hypopituitarism rates. Weighted random effects meta-analyses using the DerSimonian and Laird methods were conducted to characterize and compare effect sizes. Mixed effects regression models were used to examine correlations between potential prognostic factors and primary and secondary outcomes.

RESULTS

In total, 1533 patients across 20 published studies with acromegaly treated with SRS were included. At 5-years, estimated ER and EC rates were 43.2% (95% CI 31.7-54.6%) and 55.0% (95% CI 27.6-82.4%), respectively. At 10-years, estimated ER and EC rates were 56.9% (95% CI 47.5-66.4%) and 69.7% (95% CI 47.7-91.8%), respectively. The estimated 10-year LC rate was 92.8% (95% CI 83.0-100%). Visual toxicity and hypopituitarism following SRS were estimated to be 2.7% (95% CI 1.3-4.2%) and 26.8% (95% CI 16.9-36.7%), respectively. Every 1 Gy increase in margin prescription dose beyond 17 Gy was estimated to result in a 0.41% increased risk of visual toxicity (p = 0.03). No prognostic factors were associated with EC, ER, LC, or hypopituitarism.

CONCLUSIONS

SRS was well-tolerated in the management of pituitary acromegaly resulting in gradually improving ER and EC rates over time that approached 60% and 70%. SRS-related visual loss is an uncommon treatment-related side effect, and patient-specific clinical decision making remains critical.

Assessment of unintended shifts during frame-based stereotactic radiosurgery using cone beam computed tomography image guidance

PURPOSE

To investigate the frequency, magnitude and possible causes of frame-shifts that may occur between treatment planning and treatment delivery when performing Gamma Knife radiosurgery with rigid frame-based immobilization.

METHODS

Differences between computed tomography (CT) framed fiducial stereotactic coordinate reference and cone beam computed tomography stereotactic coordinates after image registration were recorded for 49 frame-based GK radiosurgery cases performed using the Gamma Knife Icon. Parameters recorded include rotational shifts, translational shifts, and the GK-computed Maximum Shot Displacement (MSD) between the two stereotactic coordinate spaces. Other patient-specific parameters were collected and linear regression analysis was performed to evaluate predictors of increased displacement.

RESULTS

The median values of rotational shifts were: pitch 0.14°, yaw 0.17°, and roll 0.13°. The median absolute values of translational shifts were: left-right 0.39 mm, anteroposterior 0.14 mm, and superior-inferior 0. 22 mm. The median value of MSD was 0.71 mm. Twelve cases (24.5%) had a MSD of greater than 1.0 mm. Male gender was associated with increased MSD (p = 0.013) and translational shifts (root-mean-squared value, p = 0.017). Cases with large differences between right and left sided pin lengths were also associated with increased MSD (p = 0.011).

CONCLUSIONS

The use of CBCT image guidance in frame-based GK radiosurgery allows unintended frame shifts to be identified and corrected. A significant fraction (24.5%) of patients had large enough shifts to result in a MSD of greater than 1.0 mm. Male gender and eccentrically placed frames were associated with increased MSD, and particular care should be taken in these cases.

Clinical and radiographic adverse events after Gamma Knife radiosurgery for brainstem lesions: A dosimetric analysis

OBJECTIVES

To analyze the association between dosvolume relationships and adverse events in brainstem lesions treated with Gamma Knife radiosurgery (GKRS).

METHODS

Treatment plans were generated on BrainLab Elements and GammaPlan software. Dosimetric data were analyzed as continuous variables for patients who received GKRS to brain metastases or arteriovenous malformations (AVM) within or abutting the brainstem. Adverse events were classified as clinical and/or radiographic. Logistic and cox regression were used to assess the relationship between dosimetric variables and adverse events.

RESULTS

Sixty-one patients who underwent single fraction GKRS for brain metastases or AVM were retrospectively analyzed. Median age was 62 years (range: 12-92 years) and the median prescription dose was 18 Gy (range: 13-25 Gy). Median follow-up was 6months. Clinical and radiographic complications were seen in ten (16.4%) and 17 (27.9%) patients, respectively. On logistic regression, increasing D_05% was found to be associated with an increased probability of developing a clinical complication post-GKRS (OR: 1.18; 95% CI: 1.01-1.39; p = 0.04). Furthermore, mean brainstem dose (HR: 1.43; 95% CI: 1.05-1.94; p < 0.02), D_05% (HR: 1.09; 95% CI: 1.01-1.18; p = 0.03), and D_95% (HR: 2.37; 95% CI: 0.99-5.67; p = 0.05) were associated with an increased hazard of experiencing post-GKRS complications over time.

CONCLUSIONS

Increasing D_05% to the brainstem is associated with an increased risk of developing clinical complications. Clinicians may consider this parameter in addition to fractionated stereotactic radiation therapy when well-established dose constraints are not met in this patient population. Additional data are needed to further validate these findings.

Fatal heart disease among cancer patients

As the overlap between heart disease and cancer patients increases as cancer-specific mortality is decreasing and the surviving population is aging, it is necessary to identify cancer patients who are at an increased risk of death from heart disease. The purpose of this study is to identify cancer patients at highest risk of fatal heart disease compared to the general population and other cancer patients at risk of death during the study time period. Here we report that 394,849 of the 7,529,481 cancer patients studied died of heart disease. The heart disease-specific mortality rate is 10.61/10,000-person years, and the standardized mortality ratio (SMR) of fatal heart disease is 2.24 (95% CI: 2.23–2.25). Compared to other cancer patients, patients who are older, male, African American, and unmarried are at a greatest risk of fatal heart disease. For almost all cancer survivors, the risk of fatal heart disease increases with time.

As the overlap between heart disease and cancer patients increases as cancer-specific mortality is decreasing, identifying cancer patients who are at an increased risk of death from heart disease is important. Here the authors report on risk of death from heart diseases among more than 7.5 million cancer patients.

Epidemiology of synchronous brain metastases

Background

The objectives of this study were to characterize (1) epidemiology of brain metastases at the time of primary cancer diagnosis, (2) incidence and trends of synchronous brain metastases from 2010 to 2015, and (3) overall survival (OS) of patients with synchronous brain metastases.

Methods

A total of 42 047 patients with synchronous brain metastases from 2010 to 2015 were identified from the Surveillance, Epidemiology, and End Results database. Descriptive analysis was utilized to analyze demographics and incidence. The Kaplan-Meier method and a Cox proportional hazards model were utilized to evaluate potential prognostic factors for OS.

Results

The majority of patients were diagnosed from age older than 50 (91.9%). Common primary sites included lung (80%), melanoma (3.8%), breast (3.7%), and kidney/renal pelvis (3.0%). Among pediatric patients, common primaries included kidney/renal pelvis and melanomas. The incidence was roughly 7.3 persons/100 000. Synchronous brain metastases were associated with significantly poorer OS compared to extracranial metastases alone (hazard ratio [HR] =1.56; 95% CI: 1.54-1.58; P < .001). Among patients with brain metastases, male gender (HR = 1.60 vs 1.52), age older than 65 years (HR = 1.60 vs 1.46), synchronous liver, bone, or lung metastases (HR = 1.61 vs 1.49), and earlier year of diagnosis (HR = 0.98 for each year following 2010) were associated with significantly poorer OS.

Conclusions

The vast majority of brain metastases are from lung primaries. Synchronous brain metastases are associated with poorer OS compared to extracranial metastases alone.

Long-term causes of death among pediatric patients with cancer

BACKGROUND

The objectives of this study were to characterize the risk of death (1) from the primary cancer vs competing cause of death; and (2) from various causes of death vs the general poplation. The relative risk of death after a pediatric cancer diagnosis versus the general population and the risk of death from a primary cancer diagnosis versus competing causes of death.

METHODS

This retrospective, population-based study used the Surveillance, Epidemiology, and End Results database (1980-2015) and included patients aged 0 to 19 years at the time of diagnosis. Observed deaths were calculated; the risk of death versus the general population was assessed with standardized mortality ratios (SMRs). Competing risk models for the cause of death were performed.

RESULTS

There were 58,356 patients who were diagnosed, and the mortality rate was 22.8%. To assess causes of death, 6996 patients who died during the study period were included (45,580 total person-years at risk): 5128 (73%) died of their primary cancer, and 1868 (27%) died of a competing cause. Among all patients, the rate of death from the index cancer was higher than the rate of death from another cause within the first 5 years after diagnosis. The risk of death from a nonprimary cancer began to supersede the rate of death from the primary cancer 10 years after diagnosis for patients with germ cell tumors, lymphomas, and sarcomas. SMRs for the primary cancer were highest within the first 5 years after diagnosis for all cancers (SMRs, 100-50,000; P < .0001). The risk of death from competing causes (heart disease, suicide, and sepsis) was elevated (SMR, >100; P < .001). The risk of dying of heart disease was high, especially for patients with astrocytomas (SMR, 47.84; 95% confidence interval [CI], 27.87-76.59) and neuroblastomas (SMR, 98.59; 95% CI, 47.28-181.32). The risk of dying of suicide was high in most patients, particularly for those with osteosarcomas (SMR, 111.40; 95% CI, 2.82-620.69), Hodgkin lymphomas (SMR, 62.35; 95% CI, 34.89-102.83), and gonadal germ cell tumors (SMR, 28.97; 95% CI, 12.51-57.09).

CONCLUSIONS

The cause of death for patients with gonadal germ cell tumors, lymphomas, and sarcomas is more commonly a secondary cancer or noncancerous cause than the primary disease; their risk of death from competing causes (heart disease, suicide, and sepsis) rises throughout life.

Proton beam therapy utilization in adults with primary brain tumors in the United States

The utilization of proton beam therapy (PBT) as the primary treatment of adults with primary brain tumors (APBT) was evaluated through query of the National Cancer Database (NCDB) between the years 2004 and 2015. International Classification of Diseases for Oncology code for each patient was stratified into six histology categories; high-grade gliomas, medulloblastomas, ependymomas, other gliomas, other malignant tumors, or other benign intracranial tumors. Demographics of the treatment population were also analyzed. A total of 1,296 patients received PBT during the 11-year interval for treatment of their primary brain tumor. High-grade glioma, medulloblastoma, ependymoma, other glioma, other malignant, and other benign intracranial histologies made up 39%, 20%, 13%, 12%, 13%, and 2% of the cohort, respectively. The number of patients treated per year increased from 34 to 300 in years 2004 to 2015. Histologies treated with PBT varied over the 11-year interval with high-grade gliomas comprising 75% and 45% at years 2004 and 2015, respectively. The majority of the patient population was 18-29 years of age (59%), Caucasian race (73%), had median reported income of over $63,000 (46%), were privately insured (68%), and were treated at an academic institution (70%). This study characterizes trends of malignant and benign APBT histologies treated with PBT. Our data from 2004 through 2015 illustrates a marked increase in the utilization of PBT in the treatment of APBT and shows variability in the tumor histology treated over this time.

Conventionally fractionated radiation therapy versus stereotactic body radiation therapy for locally advanced pancreatic cancer (CRiSP): An international systematic review and meta-analysis

BACKGROUND

The goal of this study was to characterize the efficacy and safety of stereotactic body radiation therapy (SBRT) versus conventionally fractionated radiation therapy with concurrent chemotherapy (CFRT) for the definitive treatment of locally advanced pancreatic cancer. The primary outcome measure was efficacy, defined by 2-year overall survival (OS). Secondary outcomes were incidence of any grade 3/4 toxicity and 1-year OS.

METHODS

A PICOS/PRISMA/MOOSE selection protocol was used to identify eligible studies. Inclusion criteria were: 1) patients diagnosed with locally advanced N0-1 M0 pancreatic cancer; 2) CFRT 1.8 to 2.0 Gy/fraction with chemotherapy per protocol or SBRT ≥5 Gy/fraction in ≤5 fractions; 3) either no control group or another definitive chemotherapy or radiation therapy arm; 4) at least 1 of the outcome measures reported; and 5) single or multi-arm phase 2/3 prospective study for CFRT and/or phase 1/2 or retrospective study for SBRT. Neoadjuvant and/or adjuvant chemotherapy was prescribed per protocol specifications. Weighted random effects meta-analyses were conducted using the DerSimonian and Laird method to characterize summary effect sizes for each outcome.

RESULTS

A total of 470 studies were initially screened; of these, 9 studies assessed SBRT and 11 studies assessed CFRT. For SBRT, the median dose was 30 Gy, and the most common regimen was 30 Gy/5 fractions. For CFRT, doses ranged from 45 to 54 Gy in 1.8- to 2.0-Gy fractions, with the majority of studies delivering 50.4 Gy in 28 fractions with concurrent gemcitabine. The random effects estimate for 2-year OS was 26.9% (95% CI, 20.6%-33.6%) for SBRT versus 13.7% (95% CI, 8.9%-19.3%) for CFRT and was statistically significant in favor of SBRT. The random effects estimate for 1-year OS was 53.7% (95% CI, 39.3%-67.9%) for SBRT versus 49.3% (95% CI, 39.3%-59.4%) for CFRT, and was not statistically significant. The random effects estimate for acute grade 3/4 toxicity was 5.6% (95% CI, 0.0%-20.0%) for SBRT versus 37.7% (95% CI, 24.0%-52.5%) for CFRT and was statistically significant in favor of SBRT. The random effects estimate for late grade 3/4 toxicity was 9.0% for SBRT (95% CI, 3.3%-17.1%) versus 10.1% (95% CI, 1.8%-23.8%) for CFRT, which was not statistically significant.

CONCLUSION

These results suggest that SBRT for LAPC may result in a modest improvement in 2-year OS with decreased rates of acute grade 3/4 toxicity and no change in 1-year-OS or late toxicity. Further study into the use of stereotactic body radiation therapy for these patients is needed.

Single fraction radiosurgery, fractionated radiosurgery, and conventional radiotherapy for spinal oligometastasis (SAFFRON): A systematic review and meta-analysis

BACKGROUND AND PURPOSE

To perform a systematic review/meta-analysis of outcomes for patients with spinal metastases treated with stereotactic radiosurgery (SRS) (either single-fraction (SF-SRS) or multiple-fraction (MF-SRS)) or conventional radiotherapy (RT).

MATERIALS AND METHODS

Thirty-seven studies were identified. Primary outcomes were 1-year local control (LC) and acute/late grade 3-5 toxicities (including vertebral compression fractures (VCF)). Weighted random effects meta-analyses using the DerSimonian and Laird methods and meta-regressions were conducted to characterize and compare effect sizes. Mixed effects regression models were used in dose analyses.

RESULTS

A total of 3237 patients with 4911 lesions were included; 43.8%, 19.7%, and 36.5% of lesions received SF-SRS, MF-SRS, or RT, respectively. SF-SRS resulted in improved 1-year LC (92.9% (95% CI: 86.4-97.4%); p = 0.007) compared to RT (81.0% (95% CI: 69.2-90.5%)) with no difference between MF-SRS (82.1%; p = 0.86) and RT. On subgroup analysis of de novo metastases, superior 1-year LC following SF-SRS (95.5% (95% CI: 87.4-99.6%)) was maintained compared to RT (83.6% (95% CI: 70.4-93.5%); p = 0.007). A 4.7% increase in LC was noted for each 10 Gy₁₀ increase in biologically effective dose (BED₁₀, assuming an alpha/beta = 10) with SRS (p < 0.001). No difference in toxicities were found between SF-SRS (0.4%), MF-SRS (0.2%), or RT (0%). Higher VCF rates were noted following SF-SRS (19.5%) vs. MF-SRS (9.6%; p = 0.039)) with no correlation between dose and VCF rates.

CONCLUSION

SF-SRS resulted in superior LC with a roughly 5% LC benefit for every 10 Gy₁₀ increase in BED₁₀ with higher VCF rates compared to MF-SRS. If LC is the goal of treatment, then SRS may be a preferred treatment modality. However, these results are hypothesis-generating, and prospective randomized clinical trials are indicated to definitively address the question of whether SRS results in improved LC compared to RT.

Integration of immuno-oncology with stereotactic radiosurgery in the management of brain metastases

AIM

Brain metastases traditionally carried a poor prognosis with treatment being a combination of surgery, whole-brain radiation therapy, and glucocorticoids; however, this treatment paradigm carried a significant amount of morbidity. In recent years, stereotactic radiosurgery (SRS), which involves the delivery of a highly conformal dose of radiation over a single session, has been shown to be an effective alternative to WBRT with excellent rates of local control and improved quality of life; however, a survival benefit has not been demonstrated. Recent developments have challenged the traditional view of the central nervous system being "immunologically privileged" which has led to a greater focus on treating these patients with systemic therapies. Immune checkpoint inhibitors (ICI) have been shown to improve survival in multiple malignancies. As a result, there has been increased utilization in combining these therapies in this setting.

METHODS

We conducted a literature search of medical databases (e.g. PubMed) for articles involving the use of immune checkpoint inhibitors and stereotactic radiosurgery in managing brain metastases.

RESULTS

Published evidence utilizing SRS and ICI is largely limited to single institution and retrospective in nature with the most common histology being melanoma.

CONCLUSION

Combination therapy with SRS and ICI appears to improve survival in patients with brain metastases. The available data are largely retrospective; therefore, ongoing and planned prospective studies are needed to further validate these findings.

Impact of Patient Stage and Disease Characteristics on the proposed Radiation Oncology Alternative Payment Model (RO-APM)

PURPOSE

The proposed Radiation Oncology Alternative Payment Model (RO-APM) released on July 10, 2019, represents a dramatic shift from fee-for-service (FFS) reimbursement in radiation therapy (RT). This study compares historical revenue at Mayo Clinic to the RO-APM and quantifies the effect that disease characteristics may have on reimbursement.

METHODS AND MATERIALS

FFS Medicare reimbursements were determined for patients undergoing RT at Mayo Clinic from 2015 to 2016. Disease categories and payment episodes were defined as per the RO-APM. Average RT episode reimbursements were reported for each disease site, except for lymphoma and metastases, and stratified by stage and disease subcategory. Comparisons with RO-APM reimbursements were made via descriptive statistics.

RESULTS

A total of 2098 patients were identified, of whom 1866 (89%) were categorized per the RO-APM; 840 (45%) of those were aged >65 years. Breast (33%), head and neck (HN) (14%), and prostate (11%) cancer were most common. RO-APM base rate reimbursements and sensitivity analysis range were lower than historical reimbursement for bladder (-40%), cervical (-34%), lung (-28%), uterine (-26%), colorectal (-24%), upper gastrointestinal (-24%), HN (-23%), pancreatic (-20%), prostate (-16%), central nervous system (-13%), and anal (-10%) and higher for liver (+24%) and breast (+36%). Historical reimbursement varied with stage (stage III vs stage I) for breast (+57%, P < .01), uterine (+53%, P = .01), lung (+50%, P < .01), HN (+24%, P = .01), and prostate (+13%, P = .01). Overall, for patients older than 65 years of age, the RO-APM resulted in a -9% reduction in total RT reimbursement compared with historical FFS (-2%, -15%, and -27% for high, mid, and low adjusted RO-APM rates).

CONCLUSIONS

Our findings indicate that the RO-APM will result in significant reductions in reimbursement at our center, particularly for cancers more common in underserved populations. Practices that care for socioeconomically disadvantaged populations may face significant reductions in revenue, which could further reduce access for this vulnerable population.

Initial Observation among Patients with Vestibular Schwannoma

Introduction  Vestibular schwannomas (VS) are slow growing tumors. Although there are a wide variety of available treatment options, these tumors are often initially observed. We aimed to establish the presenting symptoms and outcomes of patients treated with initial observation at our institution. Methods  The medical records of patients with radiographically diagnosed VS were reviewed from 1989 to 2018. Actuarial estimates of radiographic tumor control and freedom of local therapy were calculated and compared using Cox regression analyses. Results  A total of 360 patients were diagnosed with VS at our institution from 1989 through 2018 with a median age of 59.9 years. After radiographic diagnosis, 243 patients (67.5%) opted for initial observation. Local control at 1, 5, and 10 years was 91, 67, and 58%, respectively. On multivariable analysis, factors associated with shorter time to radiographic tumor progression included younger patient age ( p  = 0.016) and tumors with an extracanalicular component ( p  = 0.032). Regarding time until definitive treatment only larger baseline American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) tumor size predicted for earlier initiation of therapy ( p  < 0.001), although this was restricted to tumors with an extracanalicular component ( p  = 0.004), as opposed to purely internal auditory canal tumors ( p  = 0.839). Conclusion  Many patients who were initially observed continued to have satisfactory local control rates at 10 years. In patients with extracanalicular tumors, larger AAO-HNS tumor measurements were associated with earlier radiographic tumor progression and shorter time to local therapy, with 7 mm serving as a potential threshold value for extracanalicular tumors. Younger patients and tumors with primarily an extracanalicular portion may warrant closer observation.

Intracranial motion during frameless Gamma-Knife stereotactic radiosurgery

PURPOSE/OBJECTIVES

The Gamma-Knife radiosurgery (GKRS) (Elekta AB, Stockholm) platform delivers highly conformal and precise radiation; however, intracranial displacement during treatment allows for the potential of a marginal target-miss. Frameless (mask-based) GKRS using the Gamma Knife Icon system monitors nasal tip motion as a surrogate for intracranial motion by tracking an infrared marker using a high-definition motion management (HDMM) system. To date, there is limited data available regarding the incidence and severity of motion and factors that impact intrafraction motion when treating with frameless GKRS.

MATERIALS/METHODS

A retrospective study was performed to evaluate patients with brain tumors who were treated with frameless GKRS using the Gamma Knife Icon between May and December 2018. All patients underwent mask-based immobilization using a thermoplastic mask. Data on patient demographics, mask type, use of bite block, and number of treatments received, use of anxiolytics, treatment time, and whether a physics clearance check was performed prior to treatment were collected. For each treatment session, average displacement (mm), maximum displacement (mm) and total treatment time (min) were recorded and logistic regression analyses were performed.

RESULTS

Data was collected for 89 consecutive treatments (38 patients). Of these, an anxiolytic was used in 61 treatments and a physics clearance check was performed for 45 treatments. The median average and maximum displacement was 0.60 mm and 1.22 mm, respectively. An average displacement greater than 0.60 mm was seen with Eastern Cooperative Oncology Group performance status (ECOG) > 1, male gender, and malignant tumors (p < 0.05). Anxiolytic use prior to treatment was associated with a significant reduction in average displacement (p < 0.05). Significantly greater odds of observing a maximum displacement over 1.22 mm was seen with patients with ECOG > 1, male gender, and increased treatment time (p < 0.05). Age > 65 and anxiolytic use were associated with a significant reduction in maximum displacement (p < 0.05). Performance of clearance checks and use of bite block use did not impact average or maximum patient displacement.

CONCLUSIONS

This is the first study to evaluate patient and treatment-related factors that influence intrafraction motion during GKRS with mask-based immobilization through HDMM tracking. Increased intracranial displacement during frameless GKRS was associated with higher ECOG, male gender, increased treatment time and malignant tumors, while anxiolytics were shown to mitigate excessive motion. Radiosurgery teams should consider these patient factors when treating patients with mask immobilization.

Multidisciplinary patient-centered management of brain metastases and future directions

The incidence of brain metastasis is increasing as improvements in systemic therapy lead to increased survival. This provides new and challenging clinical decisions for patients who are trying to balance the risk of recurrence or progression with treatment-related side effects, and it requires appropriate management strategies from multidisciplinary teams. Improvements in prognostic assessment and systemic therapy with increasing activity in the brain allow for individualized care to better guide the use of local therapies and/or systemic therapy. Here, we review the current landscape of brain-directed therapy for the treatment of brain metastasis in the context of recent improved systemic treatment options. We also discuss emerging treatment strategies including targeted therapies for patients with actionable mutations, immunotherapy, modern whole-brain radiation therapy, radiosurgery, surgery, and clinical trials.

The management of elderly patients with brain metastases from breast cancer

Breast cancer is the most common type of malignancy diagnosed in women worldwide, as well as the second most common cause of metastatic brain lesions in the general population. Most breast cancer patients enrolled in clinical trials are relatively young. Elderly patients, as compared to their younger counterparts, pose unique clinical scenarios because there is limited data in this subpopulation of patients with brain metastases from breast cancer. Elderly patients are commonly treated with less aggressive therapies, perhaps due to comorbid conditions, patient preference, or other age-related concerns. Current treatment modalities offering more favorable toxicity profiles, along with more accurate prognosis, can represent an opportunity to offer improved care for this patient population. From the few efforts studying brain metastatic disease in the elderly, it is be possible to infer that age alone may not play an independent role in treatment selection and that a patient-specific evaluation and ultimate clinical judgment should guide clinical decision-making.

Public interest in stereotactic body radiation therapy (SBRT) and stereotactic radiosurgery (SRS) in the United States

Stereotactic body radiation therapy (SBRT) and stereotactic radiosurgery have become widely used in both palliative and curative treatments for variety of primary and secondary malignancies. Although the indications and use of stereotactic techniques have increased substantially in the past decades, there been no studies to date analyzing public interest in these techniques. Using Google Trends (Google LLC, Mountain View, CA), four search terms ("SBRT," "stereotactic radiosurgery," "Gamma Knife" and "Cyberknife") were analyzed in the U.S. from January 2004 to June 2019. Each term was assigned a relative interest score based on frequency of searches. "SBRT" is becoming an increasingly popular search term, reaching peak interest in October 2018. Conversely, "stereotactic radiosurgery" and "Gamma Knife" radiosurgery initially had high interest, before declining over the past decade. "Cyberknife" was most popular in the mid-2000s but decreased steadily since that time. These trends were subsequently compared against PubMed publication data over the same time.

A population-based study of cardiovascular disease mortality risk in US cancer patients

AIMS

This observational study characterized cardiovascular disease (CVD) mortality risk for multiple cancer sites, with respect to the following: (i) continuous calendar year, (ii) age at diagnosis, and (iii) follow-up time after diagnosis.

METHODS AND RESULTS

The Surveillance, Epidemiology, and End Results program was used to compare the US general population to 3 234 256 US cancer survivors (1973-2012). Standardized mortality ratios (SMRs) were calculated using coded cause of death from CVDs (heart disease, hypertension, cerebrovascular disease, atherosclerosis, and aortic aneurysm/dissection). Analyses were adjusted by age, race, and sex. Among 28 cancer types, 1 228 328 patients (38.0%) died from cancer and 365 689 patients (11.3%) died from CVDs. Among CVDs, 76.3% of deaths were due to heart disease. In eight cancer sites, CVD mortality risk surpassed index-cancer mortality risk in at least one calendar year. Cardiovascular disease mortality risk was highest in survivors diagnosed at <35 years of age. Further, CVD mortality risk is highest (SMR 3.93, 95% confidence interval 3.89-3.97) within the first year after cancer diagnosis, and CVD mortality risk remains elevated throughout follow-up compared to the general population.

CONCLUSION

The majority of deaths from CVD occur in patients diagnosed with breast, prostate, or bladder cancer. We observed that from the point of cancer diagnosis forward into survivorship cancer patients (all sites) are at elevated risk of dying from CVDs compared to the general US population. In endometrial cancer, the first year after diagnosis poses a very high risk of dying from CVDs, supporting early involvement of cardiologists in such patients.

Brain metastases from non-small cell lung cancer with EGFR or ALK mutations: A systematic review and meta-analysis of multidisciplinary approaches

BACKGROUND AND PURPOSE

To analyze outcomes of non-small cell lung cancer (NSCLC) patients with brain metastases harboring EGFR or ALK mutations and examine for differences between tyrosine kinase inhibitors (TKIs) alone, radiotherapy (RT) alone (either whole brain radiation therapy (WBRT) or stereotactic radiosurgery (SRS)), or combined TKIs and RT.

MATERIALS AND METHODS

Thirty studies were identified.

PATIENTS

with brain metastases from NSCLC.

INTERVENTION

initial TKIs alone with optional salvage RT, RT alone, or TKIs and RT.

CONTROL

wild-type NSCLC and TKIs alone for mutational and treatment analysis, respectively.

OUTCOMES

overall survival (OS) and intracranial progression-free survival (PFS).

SETTING

studies with mutation information.

RESULTS

A total of 2649 patients were included. Patients with ALK and EGFR mutations had significantly higher median OS (48.5 months, p < 0.0001; and 20.9 months; p = 0.0006, respectively) compared to wild-type patients (9.9 months). Similar median OS was noted between TKIs and RT (28.3 months), RT alone (32.2 months; p = 0.22), or TKIs alone (23.9 months; p = 0.2). Patients treated with TKIs and RT had higher median PFS (18.6 months; p = 0.06) compared to TKIs alone (13.6 months) with no difference between TKIs and RT vs. RT alone (16.9 months; p = 0.72). No PFS difference was found between WBRT and TKI (23.2 months; p = 0.72) vs. WBRT alone (24 months) or SRS and TKI (16.7 months; p = 0.56) vs. SRS alone (13.6 months).

CONCLUSION

NSCLC patients with brain metastases harboring EGFR or ALK mutations have superior OS compared to wild-type patients. No PFS or OS benefit was found with the addition of TKIs to RT.

Outcomes of stereotactic radiosurgery for pilocytic astrocytoma: an international multiinstitutional study

OBJECTIVE

The current standard initial therapy for pilocytic astrocytoma is maximal safe resection. Radiation therapy is considered for residual, recurrent, or unresectable pilocytic astrocytomas. However, the optimal radiation strategy has not yet been established. Here, the authors describe the outcomes of stereotactic radiosurgery (SRS) for pilocytic astrocytoma in a large multiinstitutional cohort.

METHODS

An institutional review board-approved multiinstitutional database of patients treated with Gamma Knife radiosurgery (GKRS) between 1990 and 2016 was queried. Data were gathered from 9 participating International Radiosurgery Research Foundation (IRRF) centers. Patients with a histological diagnosis of pilocytic astrocytoma treated using a single session of GKRS and with at least 6 months of follow-up were included in the analysis.

RESULTS

A total of 141 patients were analyzed in the study. The median patient age was 14 years (range 2-84 years) at the time of GKRS. The median follow-up was 67.3 months. Thirty-nine percent of patients underwent SRS as the initial therapy, whereas 61% underwent SRS as salvage treatment. The median tumor volume was 3.45 cm3. The tumor location was the brainstem in 30% of cases, with a nonbrainstem location in the remainder. Five- and 10-year overall survival rates at the last follow-up were 95.7% and 92.5%, respectively. Five- and 10-year progression-free survival (PFS) rates were 74.0% and 69.7%, respectively. On univariate analysis, an age < 18 years, tumor volumes < 4.5 cm3, and no prior radiotherapy or chemotherapy were identified as positive prognostic factors for improved PFS. On multivariate analysis, only prior radiotherapy was significant for worse PFS.

CONCLUSIONS

This represents the largest study of single-session GKRS for pilocytic astrocytoma to date. Favorable long-term PFS and overall survival were observed with GKRS. Further prospective studies should be performed to evaluate appropriate radiosurgery dosing, timing, and sequencing of treatment along with their impact on toxicity and the quality of life of patients with pilocytic astrocytoma.

Safety and efficacy of repeat radiosurgery for acromegaly: an International Multi-Institutional Study

PURPOSE

Surgical resection is the first line treatment for growth hormone (GH) secreting tumors. Stereotactic radiosurgery (SRS) is recommended for patients who do not achieve endocrine remission after resection. The purpose of this study was to evaluate safety and efficacy of repeat radiosurgery for acromegaly.

METHODS

Three hundred and ninety-eight patients with acromegaly treated with the Gamma Knife radiosurgery (Elekta AB, Stockholm) were identified from the International Gamma Knife Research Foundation database. Among these, 21 patients underwent repeated SRS with sufficient endocrine follow-up and 18 patients had sufficient imaging follow-up. Tumor control was defined as lack of adenoma progression on imaging. Endocrine remission was defined as a normal IGF-1 concentration while off medical therapy.

RESULTS

Median time from initial SRS to repeat SRS was 5.0 years. The median imaging and endocrine follow-up duration after repeat SRS was 3.4 and 3.8 years, respectively. The median initial marginal dose was 17 Gy, and the median repeat marginal dose was 23 Gy. Of the 18 patients with adequate imaging follow up, 15 (83.3%) patients had tumor control and of 21 patients with endocrine follow-up, 9 (42.9%) patients had endocrine remission at last follow-up visit. Four patients (19.0%) developed new deficits after repeat radiosurgery. Of these, 3 patients had neurologic deficits and 1 patient had endocrine deficit.

CONCLUSIONS

Repeat radiosurgery for persistent acromegaly offers a reasonable benefit to risk profile for this challenging patient cohort. Further studies are needed to identify patients best suited for this type of approach.

Google Search Trends in Oncology and the Impact of Celebrity Cancer Awareness

Introduction

There is widespread public interest when celebrities are diagnosed with cancer. We sought to assess how this interest impacts awareness of prevalent cancers.

Methods

We reviewed common cancer-related search terms using Google Trends (Google LLC, Mountain View, CA) between the years 2004 and 2017 and retrospectively correlated these findings with media or celebrity-related events. The Google Trends application was used to obtain the “search volume index” (SVI), defined as the number of searches for a specific term standardized to the total number of searches over that time period. Data were presented in a graphical format. Isolated peaks of greater than 25% from the baseline SVI were identified. Using the date of the peaks, a further search was performed to determine if any event in the media triggered the peak.

Results

“Lung Cancer,” “Pancreas Cancer,” “Endometrial Cancer,” “Cervical Cancer,” “Brain Cancer,” and “Glioblastoma” each had the highest peak correspond with a celebrity-related event covered in the media. These search terms displayed several additional isolated peaks, the majority of which could all be correlated with a significant media event (%). The search term “Breast Cancer” consistently had a peaked interest during October (breast cancer awareness month). Breast cancer events relating to public figures had little to no relative impact on search volume during this period. None of the other cancer search terms displayed the same cyclical pattern during their respective awareness months. Colon, rectal, and prostate cancer demonstrated stable search volumes over time, without an isolated peak.

Conclusion

Internet search activity among English speakers of most general cancer terms exhibit peaks coinciding with events that occur to celebrity figures or advances in medicines that are substantially covered in the media. In all cases but “breast cancer,” these events lend to higher search activity as compared to campaigns and awareness months. Our study suggests that media coverage of public figures with cancer may trigger substantial Internet interest in non-breast cancers, more so than traditional efforts to raise awareness.

Trends in the initial management of vestibular schwannoma in the United States

INTRODUCTION

Vestibular schwannomas are benign tumors of the 8th cranial nerve. Initial treatment options include active surveillance, surgery, and/or radiation therapy. We analyzed the United States National Cancer Database (NCDB) for patients with vestibular schwannomas and evaluated the initial management trends after diagnosis.

METHODS

We queried the NCDB for patients with vestibular schwannomas, excluding patients who did not have schwannomas of the vestibulocochlear nerve. Categorical and continuous variables were analyzed, and multivariate Cox regression analyses were performed to investigate for predictors of initial local therapy at diagnosis. All statistical analyses were performed using commercially available software (SPSS, Version 22; SPSS Inc., Chicago, IL).

RESULTS

A total of 28,446 patients met the inclusion criteria. In this cohort, 7351 (25.8%) underwent observation, 12,362 (43.5%) underwent surgical resection, 7785 (27.4%) underwent SRS, 824 (2.9%) underwent EBRT, and 124 (0.4%) underwent RT NOS. On multivariate analysis, younger age, increased distance to treating facility, Charlson/Deyo score of 1, primary payer insurance, facility location and facility type (academic or cancer center) (p < 0.001) were all factors that predicted patients undergoing initial definitive treatment.

CONCLUSION

Age, distance to treating facility, Charlson/Deyo score, primary payer, facility location, and facility type are factors that influence initial treatment for patients with vestibular schwannoma. Clinical stratification systems are needed to identify which patients would benefit most from initial local therapy versus active surveillance.

Progress Toward Long-Term Survivors of Glioblastoma

OBJECTIVE

To identify the frequency and characteristics of long-term survivors of glioblastoma.

PATIENTS AND METHODS

Using all cases of glioblastoma with histopathological confirmation in the National Cancer Database from January 1, 2004, through December 31, 2009, clinical, institutional, and treatment-related factors were evaluated with multivariable logistic regression models so as to elucidate factors independently associated with higher than 5-year overall survival after diagnosis.

RESULTS

A total of 48,652 patients met the inclusion criteria, with 2249 (4.6%) achieving 5-year survival. Factors associated with odds of improved 5-year overall survival in multivariable analysis were younger age, female sex, less medical comorbidities, nonwhite race, highest median income quartile, left-sided tumors and tumors outside the brainstem, and treatment with radiotherapy (P<.05 for all). The percentage of patients surviving 5 years remained relatively unchanged over the 6-year study period (P=.97).

CONCLUSION

Despite improvements in median and short-term overall survival shown in recent large clinical trials for glioblastoma, the percentage of patients with glioblastoma achieving 5-year overall survival remains low. This observation calls for the development of practice-redefining therapies and justifies the increased application of radical novel and experimental treatment paradigms for all patients with glioblastoma.

Pituitary Tumor Radiosurgery

Pituitary adenomas represent a common intracranial pathology, usually resulting in the systemic secretion of hormones and compression of local endocrine and optic structures, causing a wide variety of clinical sequelae. While they are typically treated with upfront endocrine and/or surgical decompressive therapy, in patients with residual, recurrent, or refractory disease, decades of data support management with stereotactic radiosurgery. This modality offers favorable local tumor control, endocrine remission rates, and infrequent toxicity. In the future, this alternative to resection will continue to gain popularity among patients and health care providers.

Radiosurgery for Glomus Tumors

Glomus tumors of the head and neck typically compress adjacent blood vessels and cranial nerves and result in varied clinical presentations. Moreover, they are seldom encountered, even at large medical centers, and specialists in neurosurgery, otolaryngology, and radiation oncology have yet to reach a generalized consensus regarding the optimal management approach. In an effort to summarize the available data and better elucidate optimal treatment and management strategies for glomus tumors, we conducted a review of the published literature on this topic with emphasis on stereotactic radiosurgery.