Barrier films or dressings for the prevention of acute radiation dermatitis in breast cancer: a systematic review and network meta-analysis.

BACKGROUND: Barrier films or dressings were reported to be effective in preventing radiation dermatitis (RD) in breast cancer patients, but their comparative efficacy is unknown. METHODS: A systematic literature search was performed on Embase, MEDLINE and Cochrane CENTRAL Registry of Clinical Trials from inception to October 20, 2023. Randomised controlled trials (RCTs) comparing barrier films or dressings to the standard of care (SOC) or other interventions were included. We estimated summary odds ratios and mean differences using network meta-analysis with random effects. This study was registered with PROSPERO (ID: CRD42023475021). RESULTS: Fourteen RCTs met inclusion criteria. Six interventions were analysed: 3M™ Moisturizing Double Barrier Cream (MDBC), 3M™ No Sting Barrier Film (BF), Hydrofilm® (HF), Mepitel® Film (MF), Silver Leaf Nylon Dressing and StrataXRT®. HF, MF and StrataXRT® reduced the incidence of moist desquamation compared to SOC (HF: OR = 0.08; p = 0.02; MF: OR = 0.31 p < 0.01; StrataXRT®: OR = 0.22, p = 0.04). The ranking of agents from most to least effective in preventing moist desquamation according to P-scores was HF (92.5%), MF (78.5%), StrataXRT® (70.1%), BF (46.4%), Silver Leaf Nylon Dressing (24.9%), MDBC (22.9%) and SOC (14.7%). Only four RCTs on HF and MF included patient-reported outcome (PRO) assessments that allowed pooling for analysis. HF and MF were more effective in reducing pain, itchiness and burning sensation compared to SOC (p < 0.01 for all symptoms). CONCLUSION: HF and MF were effective in preventing RD in breast cancer. Future RCTs should compare these interventions to effective cream preparations, such as topical corticosteroids.

Development and validation of a recursive partitioning analysis-based pretreatment decision-making tool identifying ideal candidates for spine stereotactic body radiation therapy.

BACKGROUND: This study was aimed at developing and validating a decision-making tool predictive of overall survival (OS) for patients receiving stereotactic body radiation therapy (SBRT) for spinal metastases. METHODS: Three hundred sixty-one patients at one institution were used for the training set, and 182 at a second institution were used for external validation. Treatments most commonly involved one or three fractions of spine SBRT. Exclusion criteria included proton therapy and benign histologies. RESULTS: The final model consisted of the following variables and scores: Spinal Instability Neoplastic Score (SINS) ≥ 6 (1), time from primary diagnosis < 21 months (1), Eastern Cooperative Oncology Group (ECOG) performance status = 1 (1) or ECOG performance status > 1 (2), and >1 organ system involved (1). Each variable was an independent predictor of OS (p < .001), and each 1-point increase in the score was associated with a hazard ratio of 2.01 (95% confidence interval [CI], 1.79-2.25; p < .0001). The concordance value was 0.75 (95% CI, 0.71-0.78). The scores were discretized into three groups-favorable (score = 0-1), intermediate (score = 2), and poor survival (score = 3-5)-with 2-year OS rates of 84% (95% CI, 79%-90%), 46% (95% CI, 36%-59%), and 21% (95% CI, 14%-32%), respectively (p < .0001 for each). In the external validation set (182 patients), the score was also predictive of OS (p < .0001). Increasing SINS was predictive of decreased OS as a continuous variable (p < .0001). CONCLUSIONS: This novel score is proposed as a decision-making tool to help to optimize patient selection for spine SBRT. SINS may be an independent predictor of OS.

Cost effectiveness of treatment strategies for high risk prostate cancer.

BACKGROUND: Patients with high-risk prostate cancer (HRPC) have multiple accepted treatment options. Because there is no overall survival benefit of one option over another, appropriate treatment must consider patient life expectancy, quality of life, and cost. METHODS: The authors compared quality-adjusted life years (QALYs) and cost effectiveness among treatment options for HRPC using a Markov model with three treatment arms: (1) external-beam radiotherapy (EBRT) delivered with 20 fractions, (2) EBRT with 23 fractions followed by low-dose-rate (LDR) brachytherapy boost, or (3) radical prostatectomy alone. An exploratory analysis considered a simultaneous integrated boost according to the FLAME trial (ClinicalTrials.gov identifier NCT01168479). RESULTS: Treatment strategies were compared using the incremental cost-effectiveness ratio (ICER). EBRT with LDR brachytherapy boost was a cost-effective strategy (ICER, $20,929 per QALY gained). These results were most sensitive to variations in the biochemical failure rate. However, the results still demonstrated cost effectiveness for the brachytherapy boost paradigm, regardless of any tested parameter ranges. Probabilistic sensitivity analysis demonstrated that EBRT with LDR brachytherapy was favored in 52% of 100,000 Monte Carlo iterations. In an exploratory analysis, EBRT with a simultaneous integrated boost was also a cost-effective strategy, resulting in an ICER of $62,607 per QALY gained; however, it was not cost effective compared with EBRT plus LDR brachytherapy boost. CONCLUSIONS: EBRT with LDR brachytherapy boost may be a cost-effective treatment strategy compared with EBRT alone and radical prostatectomy for HRPC, demonstrating high-value care. The current analysis suggests that a reduction in biochemical failure alone can result in cost-effective care, despite no change in overall survival.

Association between Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers and Lung Cancer.

OBJECTIVES: Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are the most commonly prescribed antihypertensives, with prior studies identifying a possible association between long-term use and increased rates of lung cancer. This study evaluated this potential association in a large population using propensity matching. METHODS: This was a population-based cohort study in a large healthcare system in three regions of the United States. Pairwise propensity score matching was performed using demographics and comorbidities. All of the adult patients in the healthcare system from January 1, 2000 to April 30, 2018 with at least 1 year of follow-up were included. RESULTS: In total, 3,253,811 patients with a median age of 59 (range 18-103) years were included. The ACEI group had a higher freedom from lung cancer versus controls at 15 years (98.47%, 95% confidence interval [CI] 98.41-98.54) versus 98.26%, (95% CI 98.20-98.33), whereas ARBs had similar rates versus controls at all time points. For patients diagnosed as having lung cancer, median all-cause survival was significantly higher in the ACEI (34.7 months, 95% CI 32.8-36.6) and ARB (30.9 months, 95% CI 28.1-33.8) groups than the control group (20.6 months, 95% CI 20.1-21.1). CONCLUSIONS: This study showed lower rates of lung cancer with ACEI use and no difference in risk with ARBs. In addition, use of these medications was found to be associated with increased survival in those diagnosed as having lung cancer. This study supports the continued use of these medications without concern for increasing the risk of lung cancer.

Acute Disseminated Intravascular Coagulation after Oxaliplatin Infusion.

Oxaliplatin is one of the most commonly used drugs for patients with colorectal cancer. It has rarely been associated with disseminated intravascular coagulation (DIC) with only 3 previously reported cases. In all those instances, the patients had started receiving oxaliplatin, developed evidence of DIC during the course of planned treatment, and recovered with supportive care. We report a case of a 71-year-old man with colorectal cancer treated successfully with an oxaliplatin-based regimen who had disease relapse after 3 years. When treated again with oxaliplatin, he developed signs of an acute hypersensitivity reaction, and eventually had signs and symptoms consistent with DIC despite appropriate management. This case is unique in that a DIC reaction evolving from a hypersensitivity reaction occurred after the patient had already tolerated the drug years earlier. It suggests a possible immune-mediated etiology to this rare occurrence that should be kept in mind while utilizing this commonly employed drug.

Caught Between a Radiation Oncology Case Rate (ROCR) and a Hard Place: Improving Proposed Radiation Oncology Alternative Payment Models.

PURPOSE: The Radiation Oncology Case Rate (ROCR) aims to shift radiation reimbursement from fee-for-service (FFS) to bundled payments, which would decouple fractionation from reimbursement in the United States. This study compares historical reimbursement rates from 3 large centers and a national Medicare sample with proposed base rates from ROCR. It also tests the impact of methodological inclusion of treatment and disease characteristics to determine if any variables are associated with greater rate differences that may lead to inequitable reimbursement. METHODS AND MATERIALS: Using Mayo Clinic electronic medical record data from 2017 to 2020 and part B claims from the Medicare 5% research identifiable files, episodic 90-day historical reimbursement rates for 15 cancer types were calculated per the ROCR payment methodology. Mayo Clinic reimbursement rates were stratified by disease and treatment characteristics and multiple linear regression was performed to assess the association of these variables on historical episode reimbursement rates. RESULTS: From Mayo Clinic, 3498 patient episodes were included and 480,526 from the research identifiable files. From both data sets, 25% of brain metastases and 13% of bone metastases episodes included ≥2 treatment courses with an average of 51 days between courses. Accounting for all 15 cancer types, ROCR base rates resulted in an average -2.4% and -2.9% reduction in rates for Mayo Clinic and the research identifiable files respectively compared with historical reimbursement. On multivariate analysis of Mayo Clinic data, treatment intent (curative vs palliative) was associated with higher historical reimbursement (+$477 to +$7417; P ≤.05) for 12 out of 12 applicable cancer types. Stage (III-IV vs I-II) was associated with higher historical reimbursement (+$1169 to +$3917; P ≤ .05) for 8 out of 12 applicable cancer types. CONCLUSIONS: Our data suggest ROCR base rates introduce an average ≤3% reimbursement rate decrease compared with historical FFS reimbursement per cancer type, which could produce the Medicare savings required for congressional approval of ROCR. Estimating comparisons with future FFS reimbursement would require consideration of additional factors such as the increased utilization of hypofractionation, proposed FFS rate cuts, and inflationary updates. A distinct rate and shortened episode duration (≤30 days) should be considered for palliative episodes. Applying a base rate modifier per cancer stage may mitigate disproportionate reductions in reimbursement for facilities with a higher volume of curative advanced-stage patients such as freestanding centers in rural settings.

Dosimetric Features of Ultra-Hypofractionated Intensity Modulated Proton Therapy for Prostate Cancer.

Purpose: To report clinical and dosimetric characteristics of 5-fraction stereotactic ablative radiotherapy (SABR) using intensity modulated proton therapy (IMPT) for localized prostate cancer. Materials and Methods: All patients receiving IMPT SABR from 2017 to 2021 for localized prostate cancer at our institution were included. Five fractions were delivered every other day to the prostate +/- seminal vesicles [clinical target volume (CTV)] with 3 mm/3% robustness. A 4-field arrangement with 2 anterior oblique and 2 opposed lateral beams was used in most patients (97%), and most (99%) had a retroprostatic hydrogel spacer. Results: A total of 534 patients with low (14%), favorable intermediate (45%), unfavorable intermediate (36%), high (4.0%), or very high-risk (0.6%) disease are evaluated. Prescription dose was 36.25 Gy (31%), 38 Gy (38%), or 40 Gy (31%) was prescribed. Median volume percentage of CTV receiving at least 100% of prescription dose [V100% (%)] was 100% [interquartile range: 99.99-100]. Rectum V50% (%), V80% (%), and V90% (%) were significantly lower in patients who had spacer, with a mean difference of -9.70%, -6.59%, and -4.42%, respectively, compared to those who did not have spacer. Femoral head dose was lower with a 4-field arrangement. Mean differences in left and right femoral head V40% (%) were -6.99% and -10.74%, respectively. Conclusion: We provide a large, novel report of patients treated with IMPT SABR for localized prostate cancer. Four-field IMPT with hydrogel spacer provides significant sparing of rectum and femoral heads without compromising target coverage.

Integration of Telemedicine Consultation Into a Tertiary Radiation Oncology Department: Predictors of Use, Treatment Yield, and Effects on Patient Population.

PURPOSE: The COVID-19 pandemic led to rapid expansion of telemedicine. The implications of telemedicine have not been rigorously studied in radiation oncology, a procedural specialty. This study aimed to evaluate the characteristics of in-person patients (IPPs) and virtual patients (VPs) who presented to a large cancer center before and during the pandemic and to understand variables affecting likelihood of receiving radiotherapy (yield) at our institution. METHODS: A total of 17,915 patients presenting for new consultation between 2019 and 2021 were included, stratified by prepandemic and pandemic periods starting March 24, 2020. Telemedicine visits included video and telephone calls. Area deprivation indices (ADIs) were also compared. RESULTS: The overall population was 56% male and 93% White with mean age of 63 years. During the pandemic, VPs accounted for 21% of visits, were on average younger than their in-person (IP) counterparts (63.3 years IP v 62.4 VP), and lived further away from clinic (215 miles IP v 402 VP). Among treated VPs, living closer to clinic was associated with higher yield (odds ratio [OR], 0.95; P < .001). This was also seen among IPPs who received treatment (OR, 0.96; P < .001); however, the average distance from clinic was significantly lower for IPPs than VPs (205 miles IP v 349 VP). Specialized radiotherapy (proton and brachytherapy) was used more in VPs. IPPs had higher ADI than VPs. Among VPs, those treated had higher ADI (P < .001). CONCLUSION: Patient characteristics and yield were significantly different between IPPs and VPs. Telemedicine increased reach to patients further away from clinic, including from rural or health care-deprived areas, allowing access to specialized radiation oncology care. Telemedicine has the potential to increase the reach of other technical and procedural specialties.

Proton versus photon craniospinal irradiation for adult medulloblastoma: A dosimetric, toxicity, and exploratory cost analysis.

Background: This study aimed to determine whether proton craniospinal irradiation (CSI) decreased the dose to normal tissue and resulted in less toxicity than photon CSI for adult patients. Methods: This single-institution retrospective analyzed differences in radiation doses, acute toxicity, and cost between proton and CSI for adult medulloblastoma patients. Results: Of 39 total patients, 20 were treated with photon CSI prior to 2015, and 19 were treated with proton CSI thereafter. Median age was 28 years (range 18-66). The molecular subtype was most commonly sonic hedgehog (68%). Patients most commonly received 36 Gy CSI in 20 fractions with a boost to 54-55.8 Gy (92%). Proton CSI delivered significantly lower mean doses to cochleae, lacrimal glands, lens, parotid glands, pharyngeal constrictors, esophagus, lungs, liver, and skin (all P < .001). Patients receiving proton CSI had significantly lower rates of acute dysphagia of any grade (5% versus 35%, P = .044) and decreased median weight loss during radiation (+1.0 versus -2.8 kg, P = .011). Weight loss was associated with acute hospitalization (P = .009). Median follow-up was 2.9 and 12.9 years for proton and photon patients, respectively, limiting late toxicity and outcome comparisons. At the last follow-up, 5 photon patients had died (2 of progressive disease, 3 without recurrence ages 41-63) and 21% had experienced major cardiovascular events. At 10 years, 89% were alive and 82% were recurrence free. Conclusions: This study demonstrates dosimetric improvements with proton CSI, potentially leading to decreased acute toxicity including dysphagia and weight loss during treatment.

Accuracy of a Cancer Registry Versus Clinical Care Team Chart Abstraction in Identifying Cancer Recurrence.

Objective: To evaluate the completeness and reliability of recurrence data from an institutional cancer registry for patients with head and neck cancer. Patients and Methods: Recurrence information was collected by radiation oncology and otolaryngology researchers. This was compared with the institutional cancer registry for continuous patients treated with radiation therapy for head and neck cancer at a tertiary cancer center. The sensitivity and specificity of institutional cancer registry data was calculated using manual review as the gold standard. False negative recurrences were compared to true positive recurrences to assess for differences in patient characteristics. Results: A total of 1338 patients who were treated from January 1, 2010, through December 31, 2017, were included in a cancer registry and underwent review. Of them, 375 (30%) had confirmed cancer recurrences, 45 (3%) had concern for recurrence without radiologic or pathologic confirmation, and 31 (2%) had persistent disease. Most confirmed recurrences were distant (37%) or distant plus locoregional (29%), whereas few were local (11%), regional (9%), or locoregional (14%) alone. The cancer registry accuracy was 89.4%, sensitivity 61%, and specificity 99%. Time to recurrence was associated with registry accuracy. True positives had recurrences at a median of 414 days vs 1007 days for false negatives. Conclusion: Currently, institutional cancer registry recurrence data lacks the required accuracy for implementation into studies without manual confirmation. Longer follow-up of cancer status will likely improve sensitivity. No identified differences in patients accounted for differences in sensitivity. New, ideally automated, data abstraction tools are needed to improve detection of cancer recurrences and minimize manual chart review.

Assessment of minimum target dose as a predictor of local failure after spine SBRT.

OBJECTIVES: Metastasis-directed stereotactic body radiation therapy (SBRT) has demonstrated robust clinical benefits in carefully selected patients, improving local control and even overall survival (OS). We assess a large database to determine clinical and dosimetric predictors of local failure after spine SBRT. METHODS: Spine SBRT treatments with imaging follow-up were identified. Patients were treated with a simultaneous integrated boost technique using 1 or 3 fractions, delivering 20-24 Gy in 1 fraction to the gross tumor volume (GTV) and 16 Gy to the low dose volume (or 27-36 Gy and 21-24 Gy for 3 fraction treatments). Exclusions included: lack of imaging follow-up, proton therapy, and benign primary histologies. RESULTS: 522 eligible spine SBRT treatments (68 % single fraction) were identified in 377 unique patients. Patients had a median OS of 43.7 months (95 % confidence interval: 34.3-54.4). The cumulative incidence of local failure was 10.5 % (7.4-13.4) at 1 year and 16.3 % (12.6-19.9) at 2 years. Local control was maximized at 15.3 Gy minimum dose for single-fraction treatment (HR = 0.31, 95 % CI: 0.17 - 0.56, p < 0.0001) and confirmed via multivariable analyses. Cumulative incidence of local failure was 6.1 % (2.6-9.4) vs. 14.2 % (8.3-19.8) at 1 year using this cut-off, with comparable findings for minimum 14 Gy. Additionally, epidural and soft tissue involvement were predictive of local failure (HR = 1.77 and 2.30). CONCLUSIONS: Spine SBRT offers favorable local control; however, minimum dose to the GTV has a strong association with local control. Achieving GTV minimum dose of 14-15.3 Gy with single fraction SBRT is recommended whenever possible.

Dose de-intensified 3-day photon, proton, or brachytherapy: a nonrandomized controlled partial breast irradiation trial.

BACKGROUND: The optimal approach for partial breast irradiation (PBI) is unknown. We investigated a novel de-intensified 3-fraction PBI regimen for photons, protons, and brachytherapy. METHODS: A multicenter nonrandomized controlled trial with primary outcome of adverse cosmesis at 3 years versus pre-PBI. Eligibility criteria were ≥ age 50 years treated with breast-conserving surgery for node-negative estrogen receptor positive (ER+) invasive breast cancer or any ductal carcinoma in-situ (DCIS) measuring ≤ 2.5 cm. Photon and proton PBI were prescribed 21.9 Gy (RBE) and brachytherapy 21 Gy in 3 fractions. Radiotherapy technique and use of adjuvant endocrine therapy was selected at physician and patient discretion. RESULTS: Between June 17, 2015 and July 13, 2017, 161 eligible patients were treated with photons (56), protons (49), or brachytherapy (56). Median patient age was 66.8 years. 126 (78.3%) had invasive breast cancer (all ER+) and 35 (21.7%) had DCIS (88.6% ER+). 54.0% of patients with invasive breast cancer and 25.8% of patients with ER+ DCIS initiated and adhered to prescribed endocrine therapy. The proportion of patients with adverse cosmesis (by trained nurse assessment) was 14.5% at baseline, 2.3% at 3 years (difference -12.2%, 95% CI (-100%, -6.4%)). Adverse cosmesis at last-follow-up, with median follow-up 5 years, was 5.7% by nurse assessment, 5.6% by panel assessment of digital photographs, and 5.2% by patient self-report. There were no observed clinically meaningful changes in other patient reported outcomes, and just two grade 2 or higher adverse events, both grade 2, in the brachytherapy cohort. 5-year local recurrence-free and progression-free survival were 98.0% and 95.5%, respectively. There were no local recurrences amongst 60 patients with invasive breast cancer and Ki67 ≤ 13.25%. CONCLUSIONS: De-intensified 3-day PBI provided favorable disease control, tolerability, and cosmetic outcomes, meeting the pre-specified criteria for acceptability. This approach is an attractive option for small node-negative ER+ BC and DCIS patients. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02453737.

Assessment of bladder filling during prostate cancer radiation therapy with ultrasound and cone-beam CT.

Prostate cancer patients undergoing external beam radiation therapy (EBRT) benefit from a full bladder to decrease bowel and bladder toxicity. Ultrasound may offer a proxy metric for evaluation, sparing CBCT dosing. Patients were prospectively enrolled pre-simulation from January 2017 to February 2018. Bladder volume was evaluated prior to RT using US daily and CBCT for three daily treatments and then weekly unless otherwise indicated. 29 patients completed median 40 days of RT, resulting in 478 CBCT and 1,099 US bladder volumes. 21 patients were treated to intact glands and 8 to the post-prostatectomy bed. Median patient age was 70 years. Bladder volume on CBCT and US positively correlated (r = 0.85), with average bladder volume for all patients of 162 mL versus 149 mL, respectively. Bladder volume during treatment was consistently lower than the volume at CT simulation (153 mL vs 194 mL, p<0.01) and progressively declined during treatment. Patients older than 70 years presented with lower average bladder volumes than those < 70 years (122 mL vs 208 mL, respectively, p<0.01). Patients with the highest agreement between CBCT and US (<10% variability) had higher average bladder volumes (192 mL vs 120 mL, p=0.01). US was found to be an accurate measure of bladder volume and may be used to monitor daily bladder volumes in patients being treated with radiation for prostate cancer.

Comparing Oncologic Outcomes and Toxicity for Combined Modality Therapy vs. Carbon-Ion Radiotherapy for Previously Irradiated Locally Recurrent Rectal Cancer.

No standard treatment paradigm exists for previously irradiated locally recurrent rectal cancer (PILRRC). Carbon-ion radiotherapy (CIRT) may improve oncologic outcomes and reduce toxicity compared with combined modality therapy (CMT). Eighty-five patients treated at Institution A with CIRT alone (70.4 Gy/16 fx) and eighty-six at Institution B with CMT (30 Gy/15 fx chemoradiation, resection, intraoperative electron radiotherapy (IOERT)) between 2006 and 2019 were retrospectively compared. Overall survival (OS), pelvic re-recurrence (PR), distant metastasis (DM), or any disease progression (DP) were analyzed with the Kaplan-Meier model, with outcomes compared using the Cox proportional hazards model. Acute and late toxicities were compared, as was the 2-year cost. The median time to follow-up or death was 6.5 years. Median OS in the CIRT and CMT cohorts were 4.5 and 2.6 years, respectively (p ≤ 0.01). No difference was seen in the cumulative incidence of PR (p = 0.17), DM (p = 0.39), or DP (p = 0.19). Lower acute grade ≥ 2 skin and GI/GU toxicity and lower late grade ≥ 2 GU toxicities were associated with CIRT. Higher 2-year cumulative costs were associated with CMT. Oncologic outcomes were similar for patients treated with CIRT or CMT, although patient morbidity and cost were lower with CIRT, and CIRT was associated with longer OS. Prospective comparative studies are needed.

Postmastectomy Intensity Modulated Proton Therapy: 5-Year Oncologic and Patient-Reported Outcomes.

PURPOSE: To report oncologic, physician-assessed, and patient-reported outcomes (PROs) for a group of women homogeneously treated with modern, skin-sparing multifield optimized pencil-beam scanning proton (intensity modulated proton therapy [IMPT]) postmastectomy radiation therapy (PMRT). METHODS AND MATERIALS: We reviewed consecutive patients who received unilateral, curative-intent, conventionally fractionated IMPT PMRT between 2015 and 2019. Strict constraints were applied to limit the dose to the skin and other organs at risk. Five-year oncologic outcomes were analyzed. Patient-reported outcomes were evaluated as part of a prospective registry at baseline, completion of PMRT, and 3 and 12 months after PMRT. RESULTS: A total of 127 patients were included. One hundred nine (86%) received chemotherapy, among whom 82 (65%) received neoadjuvant chemotherapy. The median follow-up was 4.1 years. Five-year locoregional control was 98.4% (95% CI, 93.6-99.6), and overall survival was 87.9% (95% CI, 78.7-96.5). Acute grade 2 and 3 dermatitis was seen in 45% and 4% of patients, respectively. Three patients (2%) experienced acute grade 3 infection, all of whom had breast reconstruction. Three late grade 3 adverse events occurred: morphea (n = 1), infection (n = 1), and seroma (n = 1). There were no cardiac or pulmonary adverse events. Among the 73 patients at risk for PMRT-associated reconstruction complications, 7 (10%) experienced reconstruction failure. Ninety-five patients (75%) enrolled in the prospective PRO registry. The only metrics to increase by >1 point were skin color (mean change: 5) and itchiness (2) at treatment completion and tightness/pulling/stretching (2) and skin color (2) at 12 months. There was no significant change in the following PROs: bleeding/leaking fluid, blistering, telangiectasia, lifting, arm extension, or bending/straightening the arm. CONCLUSIONS: With strict dose constraints to skin and organs at risk, postmastectomy IMPT was associated with excellent oncologic outcomes and PROs. Rates of skin, chest wall, and reconstruction complications compared favorably to previous proton and photon series. Postmastectomy IMPT warrants further investigation in a multi-institutional setting with careful attention to planning techniques.

Dosimetric Analysis of Axillary Lymph Node Coverage Using High Tangents in the Prone Position for Left-Sided Breast Cancers.

AIM/OBJECTIVE: Prone positioning is often used to reduce the dose to organs at risk during adjuvant breast irradiation. High tangents are used with supine treatments in patients with the low-volume nodal disease to increase nodal coverage while minimizing toxicities. Our study aims to evaluate nodal coverage for patients treated in the prone position with high tangents. MATERIALS AND METHODS: Our study analyzed the plans for 20 patients with early-stage, left-sided breast cancers treated at our institution from 2018 to 2019. All patients were treated in the prone position. Axillary nodal levels I-III were contoured, and treatment plans were generated using high tangents. The heart, bilateral lungs, and breast tissue were retrospectively contoured. All plans were evaluated to a dose of 42.4 Gy in 16 fractions. RESULTS: Level I lymph node levels had a mean coverage of 99% of the prescription dose (range: 98-100%). Similarly, level II coverage was approximately 88% (range: 65-100%). The mean coverage for level III was approximately 25% (range: 0-52%). The mean heart dose, mean lung volume receiving ≥20 Gy (V20) for the bilateral lungs, and ipsilateral V20 were 1.69 Gy, 1.64%, and 3.56%, respectively. CONCLUSION: Treating patients in the prone position with high tangents provides excellent coverage of axillary levels I and II, although there is minimal coverage of axillary level III. Prospective trials are needed to evaluate the clinical outcomes when treating patients with high tangents in the prone position.

Cost-Effectiveness of Treatment Strategies for Spinal Metastases.

PURPOSE: We analyzed the cost-effectiveness of standard palliative external beam radiation (EBRT, 8 Gy in 1 fraction), stereotactic body radiation therapy (SBRT, 24 Gy in 2 fractions), and radiofrequency ablation for painful spinal metastases. Single-fraction SBRT (delivering 24 Gy) was also assessed. METHODS AND MATERIALS: A Markov state transition model was constructed. Key model parameters were derived from prospective clinical trial data. Strategies were compared using the incremental cost-effectiveness ratio (ICER), with effectiveness in quality-adjusted life-years (QALYs) and a willingness-to-pay threshold of $100,000 per QALY gained. Costs included both hospital and professional costs using 2020 Medicare reimbursement. RESULTS: The base case demonstrated that 2-fraction SBRT was not cost-effective compared with single-fraction EBRT, with an ICER of $194,145 per QALY gained. Radiofrequency ablation was a more costly and less effective strategy in this model. Probabilistic sensitivity analysis demonstrated that EBRT was favored in 66% of model iterations. If median survival were improved after SBRT, 2-fraction SBRT became cost-effective, with ICERs of $80,394, $57,062, and $47,038 for 3-, 6-, and 9-month improvements in survival, respectively. Because 2-fraction SBRT data reported that 18% of patients had an indeterminant pain response at 3 months and 2-fraction SBRT is infrequently used in clinical practice, single-fraction SBRT data were also assessed. Single-fraction SBRT delivering 24 Gy was cost-effective compared with single-fraction EBRT, with an ICER of $92,833 per QALY gained. CONCLUSIONS: For appropriately chosen patients, single-fraction SBRT was more cost-effective than conventional EBRT or radiofrequency ablation. Conventional EBRT remains a cost-effective treatment for patients with poor expected survival.

Single and Multifraction Spine Stereotactic Body Radiation Therapy and the Risk of Radiation Induced Myelopathy.

Purpose: This study reports on the risk of radiation-induced myelitis (RM) of the spinal cord from a large single-institutional experience with 1 to 5 fraction stereotactic body radiation therapy (SBRT) to the spine. Methods and Materials: A retrospective review of patients who received spine SBRT to a radiation naïve level at or above the conus medullaris between 2007 and 2019 was performed. Local failure determination was based on SPIne response assessment in Neuro-Oncology criteria. RM was defined as neurologic symptoms consistent with the segment of cord irradiated in the absence of neoplastic disease recurrence and graded by Common Toxicity Criteria for Adverse Events, version 4.0. Rates of adverse events were estimated and dose-volume statistics from delivered treatment plans were extracted for the planning target volumes and spinal cord. Results: A total of 353 lesions in 277 patients were identified that met the specified criteria, for which 270, 70, and 13 lesions received 1-, 3-, and 5-fraction treatments, respectively, with a median follow-up of 46 months (95% confidence interval [CI], 41-52 months) for all surviving patients. The median overall survival was 33.0 months (95% CI, 29-43). The median D0.03cc to the spinal cord was 11.7 Gy (interquartile range [IQR], 10.5-12.4), 16.7 Gy (IQR, 12.8-20.6), and 26.0 Gy (IQR, 24.1-28.1), for 1-, 3-, 5-fractions. Using an a/b = 2Gy for the spinal cord, the median single-fraction equivalent-dose (SFED2) was 11.7 Gy (IQR, 10.2-12.5 Gy) and the normalized biological equivalent dose (nBED2/2) was 19.9 Gy (IQR, 15.4-22.8 Gy). One patient experienced grade 2 RM after a single-fraction treatment. The cumulative probability of RM was 0.3% (95% CI, 0%-2%). Conclusions: Spine SBRT is safe while limiting the spinal cord (as defined on treatment planning magnetic resonance imaging or computed tomography myelogram) D0.03cc to less than 14 Gy, 21.9 Gy, and 30 Gy, for 1, 3, and 5-fractions, consistent with standard guidelines.

Development and Assessment of a Predictive Score for Vertebral Compression Fracture After Stereotactic Body Radiation Therapy for Spinal Metastases.

IMPORTANCE: Vertebral compression fracture (VCF) is a potential adverse effect following treatment with stereotactic body radiation therapy (SBRT) for spinal metastases. OBJECTIVE: To develop and assess a risk stratification model for VCF after SBRT. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study conducted at a high-volume referral center included 331 patients who had undergone 464 spine SBRT treatments from December 2007 through October 2019. Data analysis was conducted from November 1, 2020, to August 17, 2021. Exclusions included proton therapy, prior surgical intervention, vertebroplasty, or missing data. EXPOSURES: One and 3 fraction spine SBRT treatments were most commonly delivered. Single-fraction treatments generally involved prescribed doses of 16 to 24 Gy (median, 20 Gy; range, 16-30 Gy) to gross disease compared with multifraction treatment that delivered a median of 30 Gy (range, 21-50 Gy). MAIN OUTCOMES AND MEASURES: The VCF and radiography components of the spinal instability neoplastic score were determined by a radiologist. Recursive partitioning analysis was conducted using separate training (70%), internal validation (15%), and test (15%) sets. The log-rank test was the criterion for node splitting. RESULTS: Of the 331 participants, 88 were women (27%), and the mean (IQR) age was 63 (59-72) years. With a median follow-up of 21 months (IQR, 11-39 months), we identified 84 VCFs (18%), including 65 (77%) de novo and 19 (23%) progressive fractures. There was a median of 9 months (IQR, 3-21 months) to developing a VCF. From 15 candidate variables, 6 were identified using the backward selection method, feature importance testing, and a correlation heatmap. Four were selected via recursive partitioning analysis: epidural tumor extension, lumbar location, gross tumor volume of more than 10 cc, and a spinal instability neoplastic score of more than 6. One point was assigned to each variable, and the resulting multivariable Cox model had a concordance of 0.760. The hazard ratio per 1-point increase for VCF was 1.93 (95% CI, 1.62-2.30; P < .001). The cumulative incidence of VCF at 2 years (with death as a competing risk) was 6.7% (95% CI, 4.2%-10.7%) for low-risk (score, 0-1; 273 [58.3%]), 17.0% (95% CI, 10.8%-26.7%) for intermediate-risk (score, 2; 99 [21.3%]), and 35.4% (95% CI, 26.7%-46.9%) for high-risk cases (score, 3-4; 92 [19.8%]) (P < .001). Similar results were observed for freedom from VCF using stratification. CONCLUSIONS AND RELEVANCE: The results of this cohort study identify a subgroup of patients with high risk for VCF following treatment with SBRT who may potentially benefit from undergoing prophylactic spinal stabilization or vertebroplasty.

Quality and Readability of Web-Based Information for Patients With Pancreatic Cysts: DISCERN and Readability Test Analysis.

BACKGROUND: Pancreatic cysts are a complex medical problem with several treatment options. Patients use web-based health information to understand their conditions and to guide treatment choices. OBJECTIVE: The goal of this study was to describe the quality and readability of publicly available web-based information on pancreatic cysts and to compare this information across website affiliations. METHODS: A Google search for "pancreatic cysts" was performed and the first 30 websites were evaluated. Website affiliations were classified as academic, media, nonprofit, government, or not disclosed. Information describing cancer risk was recorded. The DISCERN instrument measured the quality of content regarding treatment choices. Four standardized tests were used to measure readability. RESULTS: Twenty-one websites were included. The majority of the websites (20/21, 95%) described the cancer risk associated with pancreatic cysts. Nearly half of the websites were written by an academic hospital or organization. The average DISCERN score for all websites was 40.4 (range 26-65.5, maximum 80). Websites received low scores due to lack of references, failure to describe the risks of treatment, or lack of details on how treatment choices affect quality of life. The average readability score was 14.74 (range 5.76-23.85, maximum 19+), indicating a college reading level. There were no significant differences across website affiliation groups. CONCLUSIONS: Web-based information for patients with pancreatic cysts is of moderate quality and is written above the reading level of most Americans. Gastroenterological, cancer treatment organizations, and physicians should advocate for improving the available information by providing cancer risk stratification, treatment impact on quality of life, references, and better readability.