Radiation Dose and Fractionation for Limited-stage Small-cell Lung Cancer: Survey of US Radiation Oncologists on Practice Patterns.

BACKGROUND: Thoracic radiotherapy (TRT) with concurrent chemotherapy is standard for limited-stage small-cell lung cancer (LS-SCLC). However, the optimal dosing and fractionation remain unclear. The National Comprehensive Cancer Network guidelines have recommended either 45 Gy delivered twice daily (BID) or 60 to 70 Gy delivered once daily (QD). However, the current practice patterns among US radiation oncologists are unknown. MATERIALS AND METHODS: We surveyed US radiation oncologists using an institutional review board-approved questionnaire. The questions covered demographic data, self-rated knowledge of key trials, and treatment recommendations. RESULTS: We received 309 responses from radiation oncologists. Of the 309 radiation oncologists, 60% preferred TRT QD and 76% acknowledged QD to be more common in their practice. The respondents in academic settings were more likely to endorse BID treatment by both preference (P = .001) and actual practice (P = .009). The concordance between preferring QD and administering QD in practice was 100%. In contrast, 40% of respondents who preferred BID actually administered QD more often. Also, 15% of physicians would be unwilling to switch from QD to BID and 3% would be unwilling to switch from BID to QD, even on patient request. Most respondents (88%) recommended a dose of 45 Gy for BID treatment. For QD treatment, the division was greater, with 54% recommending 60 Gy, 30% recommending 63 to 66 Gy, and 10% recommending 70 Gy. CONCLUSION: Substantial variation exists in how US radiation oncologists approach TRT dosing and fractionation for LS-SCLC. Three quarters of our respondents reported administering TRT QD most often. The most common doses were 60 Gy QD and 45 Gy BID. The results of the present survey have provided the most up-to-date information on US practice patterns for LS-SCLC.

Tumor Treating Fields Utilization in a Glioblastoma Patient with a Preexisting Cardiac Pacemaker: The First Reported Case.

BACKGROUND: Tumor-treating fields (TTFs) have become an important, evidence-based modality in the treatment of glioblastoma (GBM). In patients requiring cardiac pacemakers, TTF therapy is complicated by theoretical concerns regarding possible electrical interaction between the devices. CASE DESCRIPTION: A 57-year-old man with past medical history of sick sinus syndrome requiring cardiac pacemaker implantation suffered an acute neurologic change associated with a left parieto-occipital lesion, which was found to be GBM. After completion of guideline-concordant chemoradiation, he chose to undergo TTF therapy. Because of the absence of cardiac symptoms and the theoretical risk of far-field sensing by the pacemaker of the TTF device (potentially resulting in pacemaker inhibition), the pacemaker was turned off before receiving TTF. Following TTF implementation, the patient responded well; he remains alive more than 25 months following his GBM diagnosis, exceeding the median 20.9-month survival of the recently completed phase III TTF randomized clinical trial for newly diagnosed GBM. Furthermore, he has exhibited neither cardiac morbidity nor adverse scalp reactions to TTF therapy. CONCLUSIONS: The first reported case of successful TTF administration in a GBM patient with a previously implanted cardiac pacemaker may allay the concerns of neuro-oncologists, cardiologists, radiation oncologists, and all certified TTF prescribers regarding the applicability of TTF in suitable candidates with preexisting cardiac pacemakers. This case indicates that TTF therapy may be efficacious in patients with indwelling magnetic resonance image-conditional cardiac pacemakers turned to the off position and that physical removal of the pacemaker is not necessary before starting TTF.

Application of tumor treating fields for newly diagnosed glioblastoma: understanding of nationwide practice patterns.

BACKGROUND: Tumor treating fields (TTF) harness magnetic fields to induce apoptosis in targeted regions. A 2015 landmark randomized phase III trial of newly diagnosed glioblastoma (GBM) patients demonstrated TTF + temozolomide to be superior to temozolomide alone. Given these results, we sought to assess practice patterns of providers in TTF utilization for GBM. METHODS: A survey was administered to practices in the United States self-identifying as specializing in radiation oncology, medical oncology, neuro-oncology, neurosurgery, and/or neurology. Responses were collected anonymously; analysis was performed using Fisher's exact test. RESULTS: A total of 106 providers responded; a minority (36%) were in private practice. Regarding case volume, 82% treated at least six high-grade gliomas/year. The provider most commonly certified to offer TTF therapy to GBM patients was the neuro-oncologist (40%), followed by the radiation oncologist (34%); 31% reported no TTF-certified physician in their practice. TTF users were more likely to have high volume, and be aware of TTF inclusion in National Comprehensive Cancer Network (NCCN) guidelines (p < 0.05). CONCLUSIONS: More than 80% of TTF for GBM in the United States is performed by groups who treat at least six high-grade gliomas per year; unfortunately more than 30% were in practices bereft of anyone certified to offer TTF therapy. These results indicate that there remains fertile soil for TTF therapy nationwide to be introduced into practices for GBM treatment. Providers seeking to refer newly diagnosed GBM patients for TTF should seek out practices with TTF user-associated characteristics to ensure optimal access for their patients.

Timing of Thoracic Radiation Therapy With Chemotherapy in Limited-stage Small-cell Lung Cancer: Survey of US Radiation Oncologists on Current Practice Patterns.

INTRODUCTION: For limited-stage small-cell lung cancer (LS-SCLC), National Comprehensive Cancer Network guidelines recommend that thoracic radiotherapy (TRT) be delivered concurrently with chemotherapy and early in the regimen, with cycle 1 or 2. Evidence is conflicting regarding the benefit of early timing of TRT. A Korean randomized trial did not see a survival difference between early (cycle 1) and late (cycle 3) TRT. Current United States (US) practice patterns are unknown. MATERIALS AND METHODS: We surveyed US radiation oncologists using an institutional review board-approved online questionnaire. Questions covered treatment recommendations, self-rated knowledge of trials, and demographics. RESULTS: We received 309 responses from radiation oncologists. Ninety-eight percent recommend concurrent chemoradiotherapy over sequential. Seventy-one percent recommend starting TRT in cycle 1 of chemotherapy, and 25% recommend starting in cycle 2. In actual practice, TRT is started most commonly in cycle 2 (48%) and cycle 1 (44%). One-half of respondents (54%) believe starting in cycle 1 improves survival compared with starting in cycle 3. Knowledge of the Korean trial was associated with flexibility in delaying TRT to cycle 2 or 3 (P = .02). Over one-third (38%) treat based on pre-chemotherapy volume. CONCLUSION: US radiation oncologists strongly align with National Comprehensive Cancer Network guidelines, which recommend early concurrent chemoradiotherapy. Nearly three-quarters of respondents prefer starting TRT with cycle 1 of chemotherapy. However, knowledge of a trial supporting a later start was associated with flexibility in delaying TRT. Treating based on pre-chemotherapy volume-endorsed by over one-third of respondents-may add unnecessary toxicity. This survey can inform development of future trials.

Prophylactic Cranial Irradiation for Limited-Stage Small-Cell Lung Cancer: Survey of US Radiation Oncologists on Current Practice Patterns.

PURPOSE: Prophylactic cranial irradiation (PCI) in patients with limited-stage small-cell lung cancer (LS-SCLC) is considered the standard of care. Meta-analysis of 7 clinical trials indicates a survival benefit to PCI, but all of these trials were conducted in the pre-magnetic resonance imaging (MRI) era. Therefore, routine brain imaging with MRI before PCI-as recommended by National Comprehensive Cancer Network guidelines-is not directly supported by the evidence. Current US practice patterns for patients with LS-SCLC are unknown. MATERIALS AND METHODS: We surveyed practicing US radiation oncologists via an institutional review board-approved online questionnaire. Questions covered demographic information and treatment recommendations for LS-SCLC. RESULTS: We received 309 responses from US radiation oncologists. Ninety-eight percent recommended PCI for patients with LS-SCLC, 96% obtained brain MRI before PCI, 33% obtained serial brain imaging with MRI after PCI to detect new metastases, and 35% recommended memantine for patients undergoing PCI. Recommending memantine was associated with fewer years of practice (P < .001), fewer lung cancer patients treated per year (P = .045), and fewer LS-SCLC patients treated per year (P = .024). CONCLUSION: Almost all responding radiation oncologists recommended PCI and pre-PCI brain MRI for LS-SCLC patients with disease responsive to initial therapy. Only a third of respondents followed these patients with serial brain MRI. Approximately one third provided memantine therapy to try to limit neurocognitive effects of PCI. Further research is warranted to determine the best treatment for patients with LS-SCLC. This survey can inform the development of future trials that depend on participation from radiation oncologists.

Impact of insurance status and race on receipt of treatment for acoustic neuroma: A national cancer database analysis.

Acoustic neuroma (AN) management involves surgery, radiation, or observation. Previous studies have demonstrated that patient race and insurance status impact in-hospital morbidity/mortality following surgery; however the nationwide impact of these demographics on the receipt of each treatment modality has not been examined. The National Cancer Data Base (NCDB) from 2004 to 2013 identified AN patients. Multivariate analysis adjusted for several variables within each treatment modality, including patient age, race, sex, income, primary payer for care, tumor size, and medical comorbidities. Patients who were African-American (OR=0.7; 95%CI=0.5-0.9; p=0.01), elderly (minimum age 65) (OR=0.4; 95%CI=0.4-0.6; p<0.0001), on Medicare (OR=0.6; 95% CI=0.4-0.7; p=0.0005), or treated at a community hospital (OR=0.4; 95%CI=0.2-0.7; p=0.007) were less likely to receive surgery. Patients on Medicaid (OR=1.2; 95%CI=0.8-1.8; p=0.04) or treated at an integrated network (OR=1.2; 95%CI=0.9-1.6; p=0.0004) were more likely to receive surgery. Patients who were elderly (OR=2.2; 95%CI=1.7-2.9; p<0.0001) or treated in a comprehensive cancer center (OR=1.5; 95%CI=1.3-1.9; p=0.02) were more likely and Medicaid patients (OR=0.8; 95%CI=0.5-1.2; p=0.04) were less likely to receive radiation. Patients who were elderly (OR=2.2; 95%CI=1.7-2.7; p<0.0001), African-American (OR=1.5; 95%CI=1.1-2.0; p=0.01), on Medicare (OR=1.8; 95%CI=1.4-2.3; p=0.0003), or treated in a community hospital (OR=3.0; 95%CI=1.6-5.6; p=0.0007) were more likely to receive observation. Patients on Medicaid (OR=0.8; 95%CI=0.5-1.2; p=0.04) or treated in an integrated network (OR=0.8; 95%CI=0.6-1.0; p=0.0001) were less likely to receive observation. African-American race, elderly age, and community hospital treatment triaged towards observation/away from surgery; age also triaged towards radiation. Conversely, integrated networks triaged towards surgery/away from observation; comprehensive cancer centers triaged towards radiation. Medicaid insurance triaged towards surgery/away from radiation/observation; this may be detrimental since lack of private insurance is a known risk factor for increased in-hospital postoperative morbidity.