Pilot study of a Spanish language measure of financial toxicity in underserved Hispanic cancer patients with low English proficiency.

Background: Financial toxicity (FT) reflects multi-dimensional personal economic hardships borne by cancer patients. It is unknown whether measures of FT-to date derived largely from English-speakers-adequately capture economic experiences and financial hardships of medically underserved low English proficiency US Hispanic cancer patients. We piloted a Spanish language FT instrument in this population. Methods: We piloted a Spanish version of the Economic Strain and Resilience in Cancer (ENRICh) FT measure using qualitative cognitive interviews and surveys in un-/under-insured or medically underserved, low English proficiency, Spanish-speaking Hispanics (UN-Spanish, n = 23) receiving ambulatory oncology care at a public healthcare safety net hospital in the Houston metropolitan area. Exploratory analyses compared ENRICh FT scores amongst the UN-Spanish group to: (1) un-/under-insured English-speaking Hispanics (UN-English, n = 23) from the same public facility and (2) insured English-speaking Hispanics (INS-English, n = 31) from an academic comprehensive cancer center. Multivariable logistic models compared the outcome of severe FT (score > 6). Results: UN-Spanish Hispanic participants reported high acceptability of the instrument (only 0% responded that the instrument was "very difficult to answer" and 4% that it was "very difficult to understand the questions"; 8% responded that it was "very difficult to remember resources used" and 8% that it was "very difficult to remember the burdens experienced"; and 4% responded that it was "very uncomfortable to respond"). Internal consistency of the FT measure was high (Cronbach's α = 0.906). In qualitative responses, UN-Spanish Hispanics frequently identified a total lack of credit, savings, or income and food insecurity as aspects contributing to FT. UN-Spanish and UN-English Hispanic patients were younger, had lower education and income, resided in socioeconomically deprived neighborhoods and had more advanced cancer vs. INS-English Hispanics. There was a higher likelihood of severe FT in UN-Spanish (OR = 2.73, 95% CI 0.77-9.70; p = 0.12) and UN-English (OR = 4.13, 95% CI 1.13-15.12; p = 0.03) vs. INS-English Hispanics. A higher likelihood of severely depleted FT coping resources occurred in UN-Spanish (OR = 4.00, 95% CI 1.07-14.92; p = 0.04) and UN-English (OR = 5.73, 95% CI 1.49-22.1; p = 0.01) vs. INS-English. The likelihood of FT did not differ between UN-Spanish and UN-English in both models (p = 0.59 and p = 0.62 respectively). Conclusion: In medically underserved, uninsured Hispanic patients with cancer, comprehensive Spanish-language FT assessment in low English proficiency participants was feasible, acceptable, and internally consistent. Future studies employing tailored FT assessment and intervention should encompass the key privations and hardships in this population.

Auto-detection and segmentation of involved lymph nodes in HPV-associated oropharyngeal cancer using a convolutional deep learning neural network.

Purpose: Segmentation of involved lymph nodes on head and neck computed tomography (HN-CT) scans is necessary for the radiotherapy planning of early-stage human papilloma virus (HPV) associated oropharynx cancers (OPC). We aimed to train a deep learning convolutional neural network (DL-CNN) to segment involved lymph nodes on HN-CT scans. Methods: Ground-truth segmentation of involved nodes was performed on pre-surgical HN-CT scans for 90 patients who underwent levels II-IV neck dissection for node-positive HPV-OPC (training/validation [n = 70] and testing [n = 20]). A 5-fold cross validation approach was used to train 5 DL-CNN sub-models based on a residual U-net architecture. Validation and testing segmentation masks were compared to ground-truth masks using predetermined metrics. A lymph auto-detection model to discriminate between "node-positive" and "node-negative" HN-CT scans was developed by thresholding segmentation model outputs and evaluated using the area under the receiver operating characteristic curve (AUC). Results: In the DL-CNN validation phase, all sub-models yielded segmentation masks with median Dice ≥ 0.90 and median volume similarity score of ≥ 0.95. In the testing phase, the DL-CNN produced consensus segmentation masks with median Dice of 0.92 (IQR, 0.89-0.95), median volume similarity of 0.97 (IQR, 0.94-0.99), and median Hausdorff distance of 4.52 mm (IQR, 1.22-8.38). The detection model achieved an AUC of 0.98. Conclusion: The results from this single-institution study demonstrate the successful automation of lymph node segmentation for patients with HPV-OPC using a DL-CNN. Future studies, including validation with an external dataset, are necessary to clarify its role in the larger radiation oncology treatment planning workflow.

Unilateral Radiation Therapy for Tonsillar Cancer: Treatment Outcomes in the Era of Human Papillomavirus, Positron-Emission Tomography, and Intensity Modulated Radiation Therapy.

PURPOSE: The goal of this study was to evaluate disease, survival, and toxic effects after unilateral radiation therapy treatment for tonsillar cancer. METHODS AND MATERIALS: A retrospective study was performed of patients treated at our institution within the period from 2000 to 2018. Summary statistics were used to assess the cohort by patient characteristics and treatments delivered. The Kaplan-Meier method was used to determine survival outcomes. RESULTS: The cohort comprised 403 patients, including 343 (85%) with clinical and/or radiographic evidence of ipsilateral cervical nodal disease and 181 (45%) with multiple involved nodes. Human papillomavirus was detected in 294 (73%) tumors. Median follow-up time was 5.8 years. Disease relapse was infrequent with local recurrence in 9 (2%) patients, neck recurrence in 13 (3%) patients, and recurrence in the unirradiated contralateral neck in 9 (2%) patients. Five- and 10-year overall survival rates were 94% and 89%, respectively. Gastrostomy tubes were needed in 32 (9%) patients, and no patient had a feeding tube 6 months after therapy. CONCLUSIONS: For patients with well-lateralized tonsillar tumors and no clinically evident adenopathy of the contralateral neck, unilateral radiation therapy offers favorable rates of disease outcomes and a relatively low toxicity profile.

Evaluation of deep learning-based multiparametric MRI oropharyngeal primary tumor auto-segmentation and investigation of input channel effects: Results from a prospective imaging registry.

BACKGROUND/PURPOSE: Oropharyngeal cancer (OPC) primary gross tumor volume (GTVp) segmentation is crucial for radiotherapy. Multiparametric MRI (mpMRI) is increasingly used for OPC adaptive radiotherapy but relies on manual segmentation. Therefore, we constructed mpMRI deep learning (DL) OPC GTVp auto-segmentation models and determined the impact of input channels on segmentation performance. MATERIALS/METHODS: GTVp ground truth segmentations were manually generated for 30 OPC patients from a clinical trial. We evaluated five mpMRI input channels (T2, T1, ADC, Ktrans, Ve). 3D Residual U-net models were developed and assessed using leave-one-out cross-validation. A baseline T2 model was compared to mpMRI models (T2 + T1, T2 + ADC, T2 + Ktrans, T2 + Ve, all five channels [ALL]) primarily using the Dice similarity coefficient (DSC). False-negative DSC (FND), false-positive DSC, sensitivity, positive predictive value, surface DSC, Hausdorff distance (HD), 95% HD, and mean surface distance were also assessed. For the best model, ground truth and DL-generated segmentations were compared through a blinded Turing test using three physician observers. RESULTS: Models yielded mean DSCs from 0.71 ± 0.12 (ALL) to 0.73 ± 0.12 (T2 + T1). Compared to the T2 model, performance was significantly improved for FND, sensitivity, surface DSC, HD, and 95% HD for the T2 + T1 model (p < 0.05) and for FND for the T2 + Ve and ALL models (p < 0.05). No model demonstrated significant correlations between tumor size and DSC (p > 0.05). Most models demonstrated significant correlations between tumor size and HD or Surface DSC (p < 0.05), except those that included ADC or Ve as input channels (p > 0.05). On average, there were no significant differences between ground truth and DL-generated segmentations for all observers (p > 0.05). CONCLUSION: DL using mpMRI provides reasonably accurate segmentations of OPC GTVp that may be comparable to ground truth segmentations generated by clinical experts. Incorporating additional mpMRI channels may increase the performance of FND, sensitivity, surface DSC, HD, and 95% HD, and improve model robustness to tumor size.

Benchmarking Outcomes for Definitive Treatment of Young-Onset, Locally Advanced Rectal Cancer.

PURPOSE: There has been an increase in the incidence of rectal cancer diagnosed in young adults (age < 50 years). We evaluated outcomes among young adults treated with pre-operative long course chemoradiation (CRT) and total mesorectal excision (TME). METHODS: The medical records of 219 patients, age 18-49, with non-metastatic, cT3-4, or cN1-2 rectal adenocarcinoma treated from 2000 to 2017 were reviewed for demographic and treatment characteristics, as well as pathologic and oncologic outcomes. The Kaplan-Meier test, log-rank test, and Cox regression analysis were used to evaluate survival outcomes. RESULTS: The median age at diagnosis was 44 years. CRT followed by TME and post-operative chemotherapy was the most frequent treatment sequence (n = 196), with FOLFOX (n = 115) as the predominant adjuvant chemotherapy. There was no difference in sex, stage, MSS/pMMR, or pCR by age (< 45 years [n = 111] vs. ≥ 45 years [n = 108]). The 5-year rates of DFS were 77.2% for all patients, 69.8% for age < 45 years and 84.7% for age ≥ 45 years (P = .01). The 5-year rates of OS were 89.6% for all patients, 85.1% for patients with age < 45 years and 94.3% for patients with age ≥ 45 years (P = .03). Age ≥ 45 years was associated with a lower risk of disease recurrence or death on multivariable Cox regression analysis (HR = 0.55, 95% CI 0.31-0.97, P = .04). CONCLUSION: Among young adults, patients with age < 45 years had lower rates of DFS and OS, compared to those with age ≥ 45 years. These outcomes could serve as a benchmark by which to evaluate newer treatment approaches.

Advances in Imaging for HPV-Related Oropharyngeal Cancer: Applications to Radiation Oncology.

While there has been an overall decline of tobacco and alcohol-related head and neck cancer in recent decades, there has been an increased incidence of HPV-associated oropharyngeal cancer (OPC). Recent research studies and clinical trials have revealed that the cancer biology and clinical progression of HPV-positive OPC is unique relative to its HPV-negative counterparts. HPV-positive OPC is associated with higher rates of disease control following definitive treatment when compared to HPV-negative OPC. Thus, these conditions should be considered unique diseases with regards to treatment strategies and survival. In order to sufficiently characterize HPV-positive OPC and guide treatment strategies, there has been a considerable effort to diagnose, prognose, and track the treatment response of HPV-associated OPC through advanced imaging research. Furthermore, HPV-positive OPC patients are prime candidates for radiation de-escalation protocols, which will ideally reduce toxicities associated with radiation therapy and has prompted additional imaging research to detect radiation-induced changes in organs at risk. This manuscript reviews the various imaging modalities and current strategies for tackling these challenges as well as provides commentary on the potential successes and suggested improvements for the optimal treatment of these tumors.

Precision association of lymphatic disease spread with radiation-associated toxicity in oropharyngeal squamous carcinomas.

PURPOSE: To determine whether patient similarity in terms of head and neck cancer spread through lymph nodes correlates significantly with radiation-associated toxicity. MATERIALS AND METHODS: 582 head and neck cancer patients received radiotherapy for oropharyngeal cancer (OPC) and had non-metastatic affected lymph nodes in the head and neck. Affected lymph nodes were segmented from pretreatment contrast-enhanced tomography scans and categorized according to consensus guidelines. Similar patients were clustered into 4 groups according to a graph-based representation of disease spread through affected lymph nodes. Correlation between dysphagia-associated symptoms and patient groups was calculated. RESULTS: Out of 582 patients, 26% (152) experienced toxicity during a follow up evaluation 6 months after completion of radiotherapy treatment. Patient groups identified by our approach were significantly correlated with dysphagia, feeding tube, and aspiration toxicity (p < .0005). DISCUSSION: Our results suggest that structural geometry-aware characterization of affected lymph nodes can be used to better predict radiation-associated dysphagia at time of diagnosis, and better inform treatment guidelines. CONCLUSION: Our work successfully stratified a patient cohort into similar groups using a structural geometry, graph-encoding of affected lymph nodes in oropharyngeal cancer patients, that were predictive of late radiation-associated dysphagia and toxicity.

Proton Therapy for HPV-Associated Oropharyngeal Cancers of the Head and Neck: a De-Intensification Strategy.

OPINION STATEMENT: The rise in the incidence of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPC), the relatively young age at which it is diagnosed, and its favorable prognosis necessitate the use of treatment techniques that reduce the likelihood of side effects during and after curative treatment. Intensity-modulated proton therapy (IMPT) is a form of radiotherapy that de-intensifies treatment through dose de-escalation to normal tissues without compromising dose to the primary tumor and involved, regional lymph nodes. Preclinical studies have demonstrated that HPV-positive squamous cell carcinoma is more sensitive to proton radiation than is HPV-negative squamous cell carcinoma. Retrospective studies comparing intensity-modulated photon (X-ray) radiotherapy to IMPT for OPC suggest comparable rates of disease control and lower rates of pain, xerostomia, dysphagia, dysgeusia, gastrostomy tube dependence, and osteoradionecrosis with IMPT-all of which meaningfully affect the quality of life of patients treated for HPV-associated OPC. Two phase III trials currently underway-the "Randomized Trial of IMPT versus IMRT for the Treatment of Oropharyngeal Cancer of the Head and Neck" and the "TOxicity Reduction using Proton bEam therapy for Oropharyngeal cancer (TORPEdO)" trial-are expected to provide prospective, level I evidence regarding the effectiveness of IMPT for such patients.

Patterns of care for pediatric patients with newly-diagnosed grade II gliomas.

PURPOSE: We describe large-scale demographic, initial treatment, and outcomes data for pediatric grade II gliomas included in the National Cancer Database from 2004 to 2014. METHODS: Our cohort included cases less than 21 years of age with pathology-confirmed disease. Logistic regressions were used to evaluate the use of chemotherapy (CT) and radiation therapy (RT). Overall survival (OS) rates were determined using Kaplan-Meier estimates and the log-rank test. RESULTS: We identified 803 cases with astrocytoma (56.2%), oligodendroglioma (26.0%), and mixed glioma/glioma NOS (17.8%) histologies. Most cases underwent surgical resection (n = 661). Whereas cases 16 to 21 years of age were more likely than cases 0 to 5 years to receive RT (OR = 7.38, 95% CI 3.58-15.21, p < 0.001), they were less likely to receive CT (OR = 0.34, 95% CI 0.22-0.52, p < 0.001). The 5-year OS rates for all cases, cases that underwent surgical resection, and cases managed with biopsy were 87.5%, 92.7%, and 63.6%, respectively. CONCLUSION: In one of the largest series of pediatric grade II gliomas, astrocytoma was the most common histology. Patterns of care and OS outcomes were similar to grade I gliomas, with surgical resection being the most common initial treatment and associated with a favorable rate of OS. Younger patients were more likely to receive post-operative CT and the use of RT increased with age.

Automatic Segmentation Using Deep Learning to Enable Online Dose Optimization During Adaptive Radiation Therapy of Cervical Cancer.

PURPOSE: This study investigated deep learning models for automatic segmentation to support the development of daily online dose optimization strategies, eliminating the need for internal target volume expansions and thereby reducing toxicity events of intensity modulated radiation therapy for cervical cancer. METHODS AND MATERIALS: The cervix-uterus, vagina, parametrium, bladder, rectum, sigmoid, femoral heads, kidneys, spinal cord, and bowel bag were delineated on 408 computed tomography (CT) scans from patients treated at MD Anderson Cancer Center (n = 214), Polyclinique Bordeaux Nord Aquitaine (n = 30), and enrolled in a Medical Image Computing & Computer Assisted Intervention challenge (n = 3). The data were divided into 255 training, 61 validation, 62 internal test, and 30 external test CT scans. Two models were investigated: the 2-dimensional (2D) DeepLabV3+ (Google) and 3-dimensional (3D) Unet in RayStation (RaySearch Laboratories). Three intensity modulated radiation therapy plans were generated on each CT of the internal and external test sets using either the manual, 2D model, or 3D model segmentations. The dose constraints followed the External beam radiochemotherapy and MRI based adaptive BRAchytherapy in locally advanced CErvical cancer (EMBRACE) II protocol, with reduced margins of 5 and 3 mm for the target and nodal planning target volume. Geometric discrepancies between the manual and predicted contours were assessed using the Dice similarity coefficient (DSC), distance-to-agreement, and Hausdorff distance. Dosimetric discrepancies between the manual and model doses were assessed using clinical indices on the manual contours and the gamma index. Interobserver variability was assessed for the cervix-uterus, parametrium, and vagina for the definition of the primary clinical target volume (CTVT) on the external test set. RESULTS: Average DSCs across all organs were 0.67 to 0.96, 0.71 to 0.97, and 0.42 to 0.92 for the 2D model and 0.66 to 0.96, 0.70 to 0.97, and 0.37 to 0.93 for the 3D model on the validation, internal, and external test sets. Average DSCs of the CTVT were 0.88 and 0.81 for the 2D model and 0.87 and 0.82 for the 3D model on the internal and external test sets. Interobserver variability of the CTVT corresponded to a mean (range) DSC of 0.85 (0.77-0.90) on the external test set. On the internal test set, the doses from the 2D and 3D model contours provided a CTVT V42.75 Gy >98% for 98% and 91% of the CT scans, respectively. On the external test set, these percentages were increased to 100% and 93% for the 2D and 3D models, respectively. CONCLUSIONS: The investigated models provided auto-segmentation of the cervix anatomy with similar performances on 2 institutional data sets and reasonable dosimetric accuracies using small planning target volume margins, paving the way to automatic online dose optimization for advanced adaptive radiation therapy strategies.

Association Between Facility Volume and Overall Survival for Patients with Grade II Meningioma after Gross Total Resection.

BACKGROUND: The role of adjuvant radiation after gross total resection (GTR) for grade II meningioma is evolving, prompting further evaluation in NRG-BN003, a phase 3 national trial. Furthermore, the relationship between facility volume and outcomes in patients with grade II meningioma after GTR has not been examined at a national level. We aim to assess overall survival (OS) of patients with grade II meningioma after GTR by surgical case volume and OS by receipt of adjuvant radiation. METHODS: We used the National Cancer Database to identity 2823 patients diagnosed with grade II meningioma who underwent GTR. Propensity score matching was applied to balance covariates in patients with grade II meningioma after GTR stratified by adjuvant radiation status. Multivariable logistic regression was used to assess factors associated with radiation receipt. Kaplan-Meier and log-rank tests were used to assess OS by facility volume. RESULTS: As facility volume increased, OS increased, with a 5-year OS of 72.8% for facilities with GTR grade II meningioma volumes of ≤8 cases per decade and 87.5% for >8 cases per decade (P < 0.0001). There was no difference in 5-year OS between GTR alone and GTR with adjuvant radiation (84.8% vs. 86.4%; P = 0.151). Covariates significantly associated with radiation receipt included facility location, facility volume, distance, and tumor size. CONCLUSIONS: Treatment at higher surgical case volume facilities is associated with improved OS for GTR grade II meningioma. These facilities also have more patients receiving adjuvant radiation. However, we observed no difference in OS between adjuvant radiation and surgery alone.

Outcomes and toxicities following stereotactic ablative radiotherapy for pulmonary metastases in patients with primary head and neck cancer.

BACKGROUND: Metastatic head and neck cancers (HNCs) predominantly affect the lungs and have a two-year overall survival (OS) of 15% to 50%, if amenable for pulmonary metastasectomy. METHODS: Retrospective review of the two-year local control (LC), local-regional control (LRC) within the same lobe, OS, and toxicity rates in consecutive patients with metastatic pulmonary HNC who underwent stereotactic ablative radiotherapy (SABR) January 2007 to May 2018. RESULTS: Evaluated 82 patients with 107 lung lesions, most commonly squamous cell carcinoma (SCC; 64%). Median follow-up was 20 months (range: 9.0-97.6). Systemic therapy administered in 34%. LC, LRC, and OS rates were 94%, 90%, and 62%. Patients with oligometastatic disease had a higher OS than polymetastatic disease, 72% vs 44% (HR = 0.30, 95% CI: 0.14-0.64; P = .008). OS in oligometastatic non-SCC and SCC were 100% and 66% (P = .03). There were no grade ≥3 toxicities. CONCLUSIONS: Metastatic pulmonary HNCs after SABR have a two-year OS rate comparable to pulmonary metastasectomy.

Modeling Complex Deformations of the Sigmoid Colon Between External Beam Radiation Therapy and Brachytherapy Images of Cervical Cancer.

PURPOSE: In this study, we investigated registration methods for estimating the large interfractional sigmoid deformations that occur between external beam radiation therapy (EBRT) and brachytherapy (BT) for cervical cancer. METHODS AND MATERIALS: Sixty-three patients were retrospectively analyzed. The sigmoid colon was delineated on 2 computed tomography images acquired during EBRT (without applicator) and BT (with applicator) for each patient. Five registration approaches were compared to propagate the contour of the sigmoid from BT to EBRT anatomies: rigid registration, commercial hybrid (ANAtomically CONstrained Deformation Algorithm), controlling ROI surface projection of RayStation, and the classical and constrained symmetrical thin-plate spline robust point matching (sTPS-RPM) methods. Deformation of the sigmoid due to insertion of the BT applicator was reported. Registration performance was compared by using the Dice similarity coefficient (DSC), distance to agreement, and Hausdorff distance. The 2 sTPS-RPM methods were compared by using surface triangle quality criteria between deformed surfaces. Using the deformable approaches, the BT dose of the sigmoid was deformed toward the EBRT anatomy. The displacement and discrepancy between the deformable methods to propagate the planned D1cm3 and D2cm3 of the sigmoid from BT to EBRT anatomies were reported for 55 patients. RESULTS: Large and complex deformations of the sigmoid were observed for each patient. Rigid registration resulted in poor sigmoid alignment with a mean DSC of 0.26. Using the contour to drive the deformation, ANAtomically CONstrained Deformation Algorithm was able to slightly improve the alignment of the sigmoid with a mean DSC of 0.57. Using only the sigmoid surface as controlling ROI, the mean DSC was improved to 0.79. The classical and constrained sTPS-RPM methods provided mean DSCs of 0.95 and 0.96, respectively, with an average inverse consistency error <1 mm. The constrained sTPS-RPM provided more realistic deformations and better surface topology of the deformed sigmoids. The planned mean (range) D1cm3 and D2cm3 of the sigmoid were 13.4 Gy (1-24.1) and 12.2 Gy (1-21.5) on the BT anatomy, respectively. Using the constrained sTPS-RPM to deform the sigmoid from BT to EBRT anatomies, these hotspots had a mean (range) displacement of 27.1 mm (6.8-81). CONCLUSIONS: Large deformations of the sigmoid were observed between the EBRT and BT anatomies, suggesting that the D1cm3 and D2cm3 of the sigmoid would unlikely to be at the same position throughout treatment. The proposed constrained sTPS-RPM seems to be the preferred approach to manage the large deformation due to BT applicator insertion. Such an approach could be used to map the EBRT dose to the BT anatomy for personalized BT planning optimization.

Spine stereotactic radiosurgery for metastatic thyroid cancer: a single-institution experience.

OBJECTIVE: Patients with metastatic thyroid cancer have prolonged survival compared to those with other primary tumors. The spine is the most common site of osseous involvement in cases of metastatic thyroid cancer. As a result, obtaining durable local control (LC) in the spine is crucial. This study aimed to evaluate the efficacy of spine stereotactic radiosurgery (SSRS) in patients with metastatic thyroid cancer. METHODS: Information on patients with metastatic thyroid cancer treated with SSRS for spinal metastases was retrospectively evaluated. SSRS was delivered with a simultaneous integrated boost technique using single- or multiple-fraction treatments. LC, defined as stable or reduced disease volume, was evaluated by examining posttreatment MRI, CT, and PET studies. RESULTS: A total of 133 lesions were treated in 67 patients. The median follow-up duration was 31 months. Dose regimens for SSRS included 18 Gy in 1 fraction, 27 Gy in 3 fractions, and 30 Gy in 5 fractions. The histology distribution was 36% follicular, 33% papillary, 15% medullary, 13% Hurthle cell, and 3% anaplastic. The 1-, 2-, and 5-year LC rates were 96%, 89%, and 82%, respectively. The median overall survival (OS) was 43 months, with 1-, 2-, and 5-year survival rates of 86%, 74%, and 44%, respectively. There was no correlation between the absolute biological equivalent dose (BED) and OS or LC. Patients with effective LC had a trend toward improved OS when compared to patients who had local failure: 68 versus 28 months (p = 0.07). In terms of toxicity, 5 vertebral compression fractures (2.8%) occurred, and only 1 case (0.6%) of greater than or equal to grade 3 toxicity (esophageal stenosis) was reported. CONCLUSIONS: SSRS is a safe and effective treatment option with excellent LC and minimal toxicity for patients with metastatic thyroid cancer. No association with increased radiation dose or BED was found, suggesting that such patients can be effectively treated with reduced dose regimens.

Stereotactic ablative radiation therapy for pulmonary metastases: Improving overall survival and identifying subgroups at high risk of local failure.

BACKGROUND & PURPOSE: Stereotactic ablative radiation therapy (SABR) is an emerging treatment option for patients with pulmonary metastases; identifying patients who would benefit from SABR can improve outcomes. MATERIALS & METHODS: We retrospectively analyzed local failure (LF), distant failure (DF), overall survival (OS), and toxicity in 317 patients with 406 pulmonary metastases treated with SABR in January 2006-September 2017 at a tertiary cancer center. RESULTS: Median follow-up time was 23 months. Primary adrenal, colorectal, sarcoma, or pancreatic ("less responsive") tumors led to high rates of LF. LF rates for patients with less responsive vs. responsive tumors were 4.6% vs. 1.6% at 12 months and 12.8% vs. 3.9% at 24 months (hazard ratio [HR] 0.29, 95% confidence interval [CI] 0.11-0.73; Log-Rank P = 0.0087). A nomogram for 24-month local control was created using Cox multivariate factors (surgical history, planning target volume, primary disease site, lung lobe location). Treating patients with ≤3 pulmonary metastases vs. >3 pulmonary metastases was associated with improved 24-month (74.2% vs. 59.3%) and 48-month (47.7% vs. 35.1%) OS (HR 0.66, 95% CI 0.47-0.95; Log-Rank P = 0.043), and reduced 12-month (22.5% vs. 50.8%) and 24-month (31.8% vs. 61.4%) intrathoracic DF (HR 0.53, 95% CI 0.38-0.74; Log-Rank P < 0.0001). The most common toxicity was asymptomatic pneumonitis (14.8%). Six patients had grade 3 events (5 pneumonitis, 1 brachial plexus). CONCLUSIONS: SABR for pulmonary metastases was effective and well tolerated. Irradiating limited intrathoracic sites of disease led to improved OS and intrathoracic DM. Higher SABR doses or surgery could be considered for less radio-responsive primary tumors.

RapidPlan development of VMAT plans for cervical cancer patients in low- and middle-income countries.

Cervical cancer has a high incidence and mortality rate in low- and middle-income countries (LMICs) largely due to limited resources and insufficient staffing. Knowledge-based planning (KBP) could alleviate understaffing issues by streamlining the radiotherapy treatment planning process. Varian's KBP system (RapidPlan) was used to develop a model capable of producing volumetric modulated arc therapy (VMAT) plans for cervical cancer patients. Plan data from 46 patients previously treated at MD Anderson Cancer Center (MDACC) were used to create and train the model which was then applied to 32 patients excluded from the training process. Dose volume histogram (DVH) values for the planning target volume (PTV_High), bladder, rectum, and bowel were evaluated for the validation plans and found to have satisfied the required PTV coverage and organ-at-risk (OAR) dose constraints. The average value for PTV_High D95.0% was 48.0 Gy (sd = 3.0 Gy) for existing clinical plans and 48.4 Gy (sd = 2.6 Gy) for the validation plans. The mean dose for the bladder, rectum, and bowel was 39.8 Gy (sd = 3.9 Gy), 41.6 Gy (sd = 5.2 Gy), and 21.6 Gy (sd = 5.0 Gy) for existing clinical plans and 38.9 Gy (sd = 4.0 Gy), 40.3 Gy (sd = 4.8 Gy), and 21.5 Gy (sd = 4.6 Gy) for validation plans, respectively. A TOST test showed that the p values for the PTV_High D95.0% (p < 0.001), rectum V30Gy (p = 0.039), and mean dose to the bladder (p = 0.0014), rectum (p = 0.025), and bowel (p = 0.006) were statistically significant within a 5% equivalence margin of the clinical value thereby providing strong evidence of equivalence. Based on this statistical analysis, it was determined that the model was capable of generating treatable VMAT plans for cervical cancer patients.

Prevalence, Predictors, and Implications for Appropriate Use of Active Surveillance Management Among Black Men Diagnosed With Low-risk Prostate Cancer.

BACKGROUND: Consensus guidelines recommend that active surveillance (AS) be considered in the management of men with low-risk prostate cancer (LRPC). The objective was to evaluate the prevalence and predictors of an AS approach in black men (BM) diagnosed with LRPC after inclusion of AS in LRPC consensus guidelines. MATERIALS AND METHODS: BM and white men (WM) diagnosed with LRPC (prostate-specific antigen ≤10 ng/mL, Gleason score [GS] ≤6, clinical stage T1-T2a) between 2010 and 2013 were identified from the National Cancer Database. Logistic regression models were used to assess the likelihood of AS over time and to examine associations between sociodemographic characteristics (SDCs) and the receipt of AS. A subanalysis was performed to assess the likelihood of GS upgrading on prostatectomy specimens for cases that received definitive treatment with radical prostatectomy. RESULTS: Overall, 9% of BM (N=15,242) with LRPC were managed with AS. The likelihood of BM undergoing AS increased from 2010 and for all subsequent years of the study period (P<0.001). Uninsured BM were twice as likely as those with private insurance to undergo AS (odds ratio [OR]=1.97; 95% confidence interval [CI], 1.51-2.58; P<0.001). BM were less likely than WM (N=86,655) to receive AS (OR=0.82; 95% CI, 0.77-0.87; P<0.001). However, on multivariate analysis adjusted for SDCs, there was no significant difference in AS utilization between the 2 race groups. Nearly half of BM (47.5%) treated with radical prostatectomy had a postprostatectomy GS≥7, and BM were 17% more likely to experience postprostatectomy upgrading to GS≥7 when compared with WM (OR=1.17; 95% CI, 1.08-1.26; P<0.001). CONCLUSIONS: The utilization of AS for BM with LRPC seems to be increasing, is influenced by SDCs, and may not differ from AS utilization among WM. Careful consideration of prostate biopsy technique and sampling as well as SDCs at time of treatment planning may be necessary to ensure adequate evaluation of prostatic disease and appropriate disease management for BM with LRPC.

Applying physical science techniques and CERN technology to an unsolved problem in radiation treatment for cancer: the multidisciplinary 'VoxTox' research programme.

The VoxTox research programme has applied expertise from the physical sciences to the problem of radiotherapy toxicity, bringing together expertise from engineering, mathematics, high energy physics (including the Large Hadron Collider), medical physics and radiation oncology. In our initial cohort of 109 men treated with curative radiotherapy for prostate cancer, daily image guidance computed tomography (CT) scans have been used to calculate delivered dose to the rectum, as distinct from planned dose, using an automated approach. Clinical toxicity data have been collected, allowing us to address the hypothesis that delivered dose provides a better predictor of toxicity than planned dose.

The use of 11carbon methionine positron emission tomography (PET) imaging to enhance radiotherapy planning in the treatment of a giant, invasive pituitary adenoma.

A 54-year-old male presented with visual loss owing to a giant, infiltrative pituitary adenoma. Following decompressive trans-sphenoidal surgery, the patient was referred for adjuvant radiotherapy. We describe the potential utility of 11carbon methionine positron emission tomography imaging in confirming the true extent of tumour infiltration, which included the cavernous sinuses and the bones of the skull base. The co-registration of positron emission tomography imaging to planning MR and CT imaging provided assurance of complete radiotherapy coverage of the target volume and assisted with the minimisation of collateral radiation dose to adjacent organs at risk.

Quantification of vaginal motion associated with daily endorectal balloon placement during whole pelvis radiotherapy for gynecologic cancers.

BACKGROUND AND PURPOSE: To quantify intra-treatment vaginal motion in women treated with daily endorectal balloon (ERB) placement and external beam radiotherapy for gynecologic cancers. MATERIALS AND METHODS: Eighteen post-hysterectomy women with gynecologic cancers underwent computed tomography (CT) simulation scans and daily treatment with ERB. Fiducial markers were placed at the vaginal apex prior to simulation and patients were counseled on a pre-treatment bladder filling protocol. Weekly to biweekly verification CT scans were used to calculate the intra-treatment change in bladder volumes, rectal volumes, and fiducial coordinates along all axes. The planning target volume (PTV) margins required to encompass 95% of intra-treatment fiducial movement were calculated using the van Herk margin recipe. RESULTS: The median bladder volume was 223 (range, 29-879)cc for verification CT scans. Mean intra-treatment fiducial displacements were 1.7 (range, 0-9.1)mm, 2.9 (range, 0-15.5)mm, and 2.5 (range, 0-11.8)mm along the left-right (L/R), superior-inferior (S/I), and anterior-posterior (A/P) axes, respectively. The van Herk PTV margins were 3mm (L/R), 10mm (S/I) and 7mm (A/P). CONCLUSION: When compared to existing studies, the use of daily ERB with post-hysterectomy radiotherapy reduces vaginal motion along the A/P axis. The impact of variable bladder filling on vaginal motion is most evident along the S/I axis.