A Multi-Institutional Experience of MR-Guided Liver Stereotactic Body Radiation Therapy.

PURPOSE: Daily magnetic resonance (MR)-guided radiation has the potential to improve stereotactic body radiation therapy (SBRT) for tumors of the liver. Magnetic resonance imaging (MRI) introduces unique variables that are untested clinically: electron return effect, MRI geometric distortion, MRI to radiation therapy isocenter uncertainty, multileaf collimator position error, and uncertainties with voxel size and tracking. All could lead to increased toxicity and/or local recurrences with SBRT. In this multi-institutional study, we hypothesized that direct visualization provided by MR guidance could allow the use of small treatment volumes to spare normal tissues while maintaining clinical outcomes despite the aforementioned uncertainties in MR-guided treatment. METHODS AND MATERIALS: Patients with primary liver tumors or metastatic lesions treated with MR-guided liver SBRT were reviewed at 3 institutions. Toxicity was assessed using National Cancer Institute Common Terminology Criteria for Adverse Events Version 4. Freedom from local progression (FFLP) and overall survival were analyzed with the Kaplan-Meier method and χ2 test. RESULTS: The study population consisted of 26 patients: 6 hepatocellular carcinomas, 2 cholangiocarcinomas, and 18 metastatic liver lesions (44% colorectal metastasis). The median follow-up was 21.2 months. The median dose delivered was 50 Gy at 10 Gy/fraction. No grade 4 or greater gastrointestinal toxicities were observed after treatment. The 1-year and 2-year overall survival in this cohort is 69% and 60%, respectively. At the median follow-up, FFLP for this cohort was 80.4%. FFLP for patients with hepatocellular carcinomas, colorectal metastasis, and all other lesions were 100%, 75%, and 83%, respectively. CONCLUSIONS: This study describes the first clinical outcomes of MR-guided liver SBRT. Treatment was well tolerated by patients with excellent local control. This study lays the foundation for future dose escalation and adaptive treatment for liver-based primary malignancies and/or metastatic disease.

The role of radiation therapy in the treatment of Stage II endometrial cancer: A large database study.

PURPOSE: The optimum adjuvant treatment for Stage II endometrial cancer patients is unknown. External beam radiation therapy (EBRT) is often considered the standard of care; however, retrospective series suggest that brachytherapy (BT) alone may be sufficient for selected patients. As randomized data are lacking, we used a large database to explore this question. METHODS AND MATERIALS: The National Cancer Data Base was queried for patients with pathologic International Federation of Gynecology and Obstetrics Stage II disease. Demographic, clinic-pathologic, and treatment details were compared between patients. Multivariable analysis was used to determine factors associated with receiving radiation therapy (RT). To account for imbalances between groups, a matched-pair analysis was completed. RESULTS: Eight thousand one hundred forty patients were included. RT was associated with overall survival (OS), with EBRT (hazard ratio [HR] 0.64), BT (HR 0.47), and combination (HR 0.54) showing increased OS on univariate analysis. Facility, urban location, diagnosis year, hysterectomy type, and chemotherapy did not reach significance. On multivariate analysis, RT was associated with OS, with EBRT (HR 0.69), BT (HR 0.60), and combination (HR 0.54) showing benefit. Using propensity-score matching, RT continued to show improved OS regardless of type: BT (82% vs. 73% 5-year OS) and EBRT (77% vs. 71%). BT as compared to EBRT had equivalent survival (81% vs. 79%, not statistically significant). CONCLUSION: This study of over 8,000 patients demonstrates that adjuvant RT confers a survival benefit in Stage II endometrial cancer and supports the continued use of RT in these patients. BT alone may be reasonable in carefully selected patients.

RTAnswers Online Patient Education Materials Deviate From Recommended Reading Levels.

OBJECTIVE: Patients are turning to the Internet more often for cancer-related information. Oncology organizations need to ensure that appropriately written information is available for patients online. The aim of this study was to determine whether the readability of radiation oncology online patient information (OPI) provided by RTAnswers (RTAnswers.org, created by the American Society for Radiation Oncology) is written at a sixth-grade level as recommended by the National Institutes of Health (NIH), the U.S Department of Health and Human Services (HHS), and the American Medical Association (AMA). METHODS: RTanswers.org was accessed and online patient-oriented brochures for 13 specific disease sites were analyzed. Readability of OPI from RTAnswers was assessed using 10 common readability tests: New Dale-Chall Test, Flesch Reading Ease Score, Coleman-Liau Index, Flesch-Kinkaid Grade Level, FORCAST test, Fry Score, Simple Measure of Gobbledygook, Gunning Frequency of Gobbledygook, New Fog Count, and Raygor Readability Estimate. RESULTS: A composite grade level of readability was constructed using the 8 readability measures that provide a single grade-level output. The grade levels computed by each of these 8 tests were highly correlated (SI alpha = 0.98). The composite grade level for these disease site-specific brochures was 11.6 ± 0.83, corresponding to a senior in high school, significantly higher than the target sixth-grade level (p < 0.05) recommended by the NIH, HHS, and AMA. CONCLUSION: Patient educational material provided by RTAnswers.org is written significantly above the target reading level. Simplifying and rewording this information could improve patients' understanding of radiation therapy and improve treatment adherence and outcomes.

Impact of prone versus supine positioning on small bowel dose with pelvic intensity modulated radiation therapy.

PURPOSE: To report the results of a prospective study that compares small bowel doses during prone and supine pelvic intensity modulated radiation therapy. METHODS AND MATERIALS: Ten patients receiving pelvic radiation therapy each had 2 intensity modulated radiation therapy plans generated: supine and prone on a belly board (PBB). Computed tomography on rails was performed weekly throughout treatment in both positions (10 scans per patient). After image fusion, doses to small bowel (SB) loops and clinical target volume were calculated for each scan. Changes between the planned and received doses were analyzed and compared between positions. The impact of bladder filling on SB dose was also assessed. RESULTS: Prone treatment was associated with significantly lower volumes of SB receiving ≥20 Gy. On average, prone on a belly board positioning reduced the volume of SB receiving a given dose of radiation by 28% compared with supine positioning. Target coverage throughout the treatment course was similar in both positions with an average minimum clinical target volume dose of 88% of the prescribed prone dose and 89% of the supine (P = .54). For supine treatment, SB dose was inversely correlated with bladder filling (P = .001-.013; P > .15 for prone). For 96% of treatments, the volume of SB that received a given dose deviated >10% from the plan. The deviation between the planned and delivered doses to SB did not differ significantly between the positions. CONCLUSIONS: Prone positioning on a belly board during pelvic IMRT consistently reduces the volume of SB that receives a broad range of radiation doses. Prone IMRT is associated with interfraction dose variation to SB that is similar to that of supine positioning. These findings suggest that prone positioning with daily image guided radiation therapy is an effective method for maximizing SB sparing during pelvic IMRT.

Dosimetric Comparison of Real-Time MRI-Guided Tri-Cobalt-60 Versus Linear Accelerator-Based Stereotactic Body Radiation Therapy Lung Cancer Plans.

PURPOSE: Magnetic resonance imaging-guided radiation therapy has entered clinical practice at several major treatment centers. Treatment of early-stage non-small cell lung cancer with stereotactic body radiation therapy is one potential application of this modality, as some form of respiratory motion management is important to address. We hypothesize that magnetic resonance imaging-guided tri-cobalt-60 radiation therapy can be used to generate clinically acceptable stereotactic body radiation therapy treatment plans. Here, we report on a dosimetric comparison between magnetic resonance imaging-guided radiation therapy plans and internal target volume-based plans utilizing volumetric-modulated arc therapy. MATERIALS AND METHODS: Ten patients with early-stage non-small cell lung cancer who underwent radiation therapy planning and treatment were studied. Following 4-dimensional computed tomography, patient images were used to generate clinically deliverable plans. For volumetric-modulated arc therapy plans, the planning tumor volume was defined as an internal target volume + 0.5 cm. For magnetic resonance imaging-guided plans, a single mid-inspiratory cycle was used to define a gross tumor volume, then expanded 0.3 cm to the planning tumor volume. Treatment plan parameters were compared. RESULTS: Planning tumor volumes trended larger for volumetric-modulated arc therapy-based plans, with a mean planning tumor volume of 47.4 mL versus 24.8 mL for magnetic resonance imaging-guided plans ( P = .08). Clinically acceptable plans were achievable via both methods, with bilateral lung V20, 3.9% versus 4.8% ( P = .62). The volume of chest wall receiving greater than 30 Gy was also similar, 22.1 versus 19.8 mL ( P = .78), as were all other parameters commonly used for lung stereotactic body radiation therapy. The ratio of the 50% isodose volume to planning tumor volume was lower in volumetric-modulated arc therapy plans, 4.19 versus 10.0 ( P < .001). Heterogeneity index was comparable between plans, 1.25 versus 1.25 ( P = .98). CONCLUSION: Magnetic resonance imaging-guided tri-cobalt-60 radiation therapy is capable of delivering lung high-quality stereotactic body radiation therapy plans that are clinically acceptable as compared to volumetric-modulated arc therapy-based plans. Real-time magnetic resonance imaging provides the unique capacity to directly observe tumor motion during treatment for purposes of motion management.

Radiotherapeutic management of vestibular schwannomas using size- and location-adapted fractionation regimens to maximize the therapeutic ratio.

BACKGROUND: We evaluated and compared the radiographic and clinical outcomes of patients with vestibular schwannomas treated with single fraction stereotactic radiosurgery (SRS), 5 fractions of hypofractionated stereotactic radiation therapy (hSRT), or 25 to 30 fractions of conventionally fractionated stereotactic radiation therapy (cfSRT). METHODS AND MATERIALS: Fifty-six patients treated with LINAC-based SRS (median, 12.5 Gy), hSRT (25 Gy), or cfSRT (median, 54 Gy) were retrospectively reviewed. Fractionation was based on the size of the tumor, proximity to the brainstem, and potential risk of neurological sequelae. Median follow-up time was 55.2 months. RESULTS: The pretreatment median tumor diameter was significantly smaller for SRS (1.14 cm) compared with hSRT (1.7 cm) (P = .03) and cfSRT (2.0 cm) (P < .001). The overall local tumor control was 96.4%: 100% SRS, 100% hSRT, and 90% cfSRT (P = .19). Tumor regression was observed in 53.3% of SRS, 76.2% of hSRT, and 90% of cfSRT (P = .05). There was less transient expansion of tumors treated with cfSRT (5%) than with SRS (53.3%) or hSRT (28.6%) (P = .005). The median time to regression was 13.8 months for SRS, 14.2 months for hSRT, and 5.5 months for cfSRT (P = .34). There was a 3.6% incidence of grade 3 trigeminal neuropathy, but there was no grade 3 facial neuropathy. CONCLUSIONS: All 3 regimens demonstrated similar excellent local control with minimal toxicity; however, the ability of hSRT to treat larger tumors with comparable outcomes to SRS and greater patient convenience when compared with cfSRT suggest that hSRT may offer the optimal treatment approach.

Outcomes for patients with head and neck squamous cell carcinoma presenting with N3 nodal disease.

BACKGROUND: The present study evaluated clinical outcomes for patients with head and neck squamous cell carcinoma presenting with N3 nodal disease. METHODS: A retrospective analysis of N3 head and neck squamous cell carcinoma patients was performed. Pearson chi-square and Wilcoxon signed-rank tests were used to analyze patient demographics, disease characteristics, and treatment variables. Survival was evaluated using Kaplan-Meier curves with the log-rank test. Univariate analysis using Cox proportional hazards models was used to define factors associated with overall survival. Patient and tumor characteristics associated with treatment assignments were analyzed by univariate multinomial logistic regression. RESULTS: We identified 36 patients with radiographically-defined N3 disease. For the entire cohort, median follow-up was 23.6 (range 2.8-135.0) months, and overall survival was 60% at 2 years and 30% at 5 years. Overall survival was similar between patients receiving primary surgery, radiotherapy, or chemoradiotherapy (p = 0.10). Primary, regional, and distant control at 5 years was 71%, 66%, and 53%, respectively. There was a trend towards improved regional control with primary surgery (p = 0.07). Planned neck dissection following primary chemoradiotherapy did not improve regional control (p = 0.55). Patients with p16-positive tumors exhibited improved overall (p = 0.05) and metastatic recurrence-free survival (p < 0.05). There were no factors predictive of treatment assignment nor factors associated with overall survival, local and regional control, or distant metastases free-survival on univariate analysis. CONCLUSIONS: Patients with N3 head and neck squamous cell carcinoma exhibit 5-year overall survival rates of approximately 30% regardless of treatment modality. Planned neck dissection does not improve regional control in patients undergoing definitive chemoradiotherapy. p16-positive patients represent a favorable cohort. Distant failure comprises the major failure pattern and should be the focus of future studies in improving the outcome of this patient cohort.

Readability of Online Patient Educational Resources Found on NCI-Designated Cancer Center Web Sites.

BACKGROUND: The NIH and Department of Health & Human Services recommend online patient information (OPI) be written at a sixth grade level. We used a panel of readability analyses to assess OPI from NCI-Designated Cancer Center (NCIDCC) Web sites. METHODS: Cancer.gov was used to identify 68 NCIDCC Web sites from which we collected both general OPI and OPI specific to breast, prostate, lung, and colon cancers. This text was analyzed by 10 commonly used readability tests: the New Dale-Chall Readability Formula, Flesch Reading Ease scale, Flesch-Kinaid Grade Level, FORCAST scale, Fry Readability Graph, Simple Measure of Gobbledygook test, Gunning Frequency of Gobbledygook index, New Fog Count, Raygor Readability Estimate Graph, and Coleman-Liau Index. We tested the hypothesis that the readability of NCIDCC OPI was written at the sixth grade level. Secondary analyses were performed to compare readability of OPI between comprehensive and noncomprehensive centers, by region, and to OPI produced by the American Cancer Society (ACS). RESULTS: A mean of 30,507 words from 40 comprehensive and 18 noncomprehensive NCIDCCs was analyzed (7 nonclinical and 3 without appropriate OPI were excluded). Using a composite grade level score, the mean readability score of 12.46 (ie, college level: 95% CI, 12.13-12.79) was significantly greater than the target grade level of 6 (middle-school: P<.001). No difference between comprehensive and noncomprehensive centers was identified. Regional differences were identified in 4 of the 10 readability metrics (P<.05). ACS OPI provides easier language, at the seventh to ninth grade level, across all tests (P<.01). CONCLUSIONS: OPI from NCIDCC Web sites is more complex than recommended for the average patient.

Management of leptomeningeal metastases: Prognostic factors and associated outcomes.

Limited data are currently available to direct treatment recommendations in the management of leptomeningeal metastases (LM). Here we review treatment modalities clinicians should understand in order to manage patients with LM. We first describe our institution's experience with the treatment of LM and use this dataset to frame the discussion of LM management. Between 1999 and 2014, 1361 patients with central nervous system metastases were reviewed, 124 (9.1%) had radiographic evidence of LM, and these patients form the cohort for this analysis. Mean age at diagnosis of LM was 52years. Median survival for the entire cohort was 2.3months. The most common primary malignancies were non-small cell lung cancer (25.8%), breast cancer (17.7%), small cell lung cancer (16.9%) and melanoma (8.9%). Univariate analyses demonstrated that greater Karnofsky Performance Status (KPS) (p=0.001) and administration of systemic chemotherapy (p<0.001) resulted in improved median survival. Multivariate Cox analyses revealed that receipt of chemotherapy and a complete course of whole brain radiotherapy (WBRT) (median dose 30Gy in 10 fractions, range 24-40Gy) were predictive of longer survival, (p=0.013 and 0.019, respectively). These data suggest that there is a group of patients with good KPS who may experience significantly longer median survival than expected. Multivariate analysis from this single institution retrospective study demonstrated a benefit for WBRT and chemotherapy in individuals with good KPS. These findings provide contemporary data from a large cohort of LM patients, which may be utilized to guide treatment recommendations, assist in patient counseling and direct future investigations into optimization of treatment regimens.

Gadoxetate for direct tumor therapy and tracking with real-time MRI-guided stereotactic body radiation therapy of the liver.

SBRT is increasingly utilized in liver tumor treatment. MRI-guided RT allows for real-time MRI tracking during therapy. Liver tumors are often poorly visualized and most contrast agents are transient. Gadoxetate may allow for sustained tumor visualization. Here, we report on the first use of gadoxetate during real-time MRI-guided SBRT.

Using functional theory to promote HIV testing: the impact of value-expressive messages, uncertainty, and fear.

This study tests the utility of the functional theory of attitudes and arousal of fear in motivating college students to get tested for HIV. It is argued from the perspective of functional theory that value-expressive appeals to get tested for the purpose of taking care of one's own health could be effective if that goal is desired by message targets who are sexually active and unaware of their sexually transmitted disease status. As part of the process, the effectiveness of these appeals is increased by the arousal of uncertainty and fear. A model detailing the mediating processes is proposed and found to be consistent with the data. Overall, messages advocating testing for the self-interested reason of one's own health were more effective than messages advocating testing for the goal of protecting one's partners.