Stereotactic radiosurgery for prostate cancer spine metastases: local control and fracture risk using a simultaneous integrated boost approach.

OBJECTIVE: Variation exists in approaches to delivery of spine stereotactic radiosurgery (SSRS). Here, the authors describe outcomes following single-fraction SSRS performed using a simultaneous integrated boost for the treatment of prostate cancer spine metastases. METHODS: Health records of patients with prostate cancer spine metastases treated with single-fraction SSRS at the authors' institution were reviewed. Treatment was uniform, with 16 Gy to the clinical tumor volume and 18 Gy to the gross tumor volume. The primary endpoint was local recurrence, with secondary endpoints including vertebral fracture and overall survival. Univariate and multivariate competing risk regression models made using the Fine and Gray method were used to identify factors predictive of local recurrence, considering death to be a competing event for local recurrence. RESULTS: A total of 87 targets involving 108 vertebrae in 68 patients were included, with a median follow-up of 22.5 months per treated target. The 1-, 2-, and 4-year cumulative incidence rates of local failure for all targets were 4.6%, 8.4%, and 19%, respectively. The presence of epidural disease (subdistribution hazard ratio [sHR] 5.43, p = 0.04) and SSRS as reirradiation (sHR 16.5, p = 0.02) emerged as significant predictors of local failure in a multivariate model. Hormone sensitivity did not predict local control. Vertebral fracture incidence rates leading to symptoms or requiring intervention at 1, 2, and 4 years were 1.1%, 3.7%, and 8.4%, respectively. In an exploratory analysis of patterns of failure, 3 (25%) failures occurred in the epidural space and only 1 (8%) occurred clearly in the clinical tumor volume. There were several lesions for which the precise location of failure with regard to target volumes was unclear. CONCLUSIONS: High rates of local control were observed, particularly for radiotherapy-naïve lesions without epidural disease. Hormone sensitivity was not predictive of local control in this cohort and fracture risk was low. Further research is needed to better predict which patients are at high risk of recurrence and who might benefit from treatment escalation.

Outcomes and Pattern of Care for Spinal Myxopapillary Ependymoma in the Modern Era-A Population-Based Observational Study.

(1) Background: Myxopapillary ependymoma (MPE) is a rare tumor of the spine, typically slow-growing and low-grade. Optimal management strategies remain unclear due to limited evidence given the low incidence of the disease. (2) Methods: We analyzed data from 1197 patients with spinal MPE from the Surveillance, Epidemiology, and End Results (SEER) database (2000-2020). Patient demographics, treatment modalities, and survival outcomes were examined using statistical analyses. (3) Results: Most patients were White (89.9%) with a median age at diagnosis of 42 years. Surgical resection was performed in 95% of cases. The estimated 10-year overall survival was 91.4%. Younger age (hazard ratio (HR) = 1.09, p < 0.001) and receipt of surgery (HR = 0.43, p = 0.007) were associated with improved survival. Surprisingly, male sex was associated with worse survival (HR = 1.86, p = 0.008) and a younger age at diagnosis compared to females. (4) Conclusions: This study, the largest of its kind, underscores the importance of surgical resection in managing spinal MPE. The unexpected association between male sex and worse survival warrants further investigation into potential sex-specific pathophysiological factors influencing prognosis. Despite limitations, our findings contribute valuable insights for guiding clinical management strategies for spinal MPE.

Prolonged complete response to adjuvant tepotinib in a patient with newly diagnosed disseminated glioblastoma harboring mesenchymal-epithelial transition fusion.

The prognosis of patients with glioblastoma (GBM) remains poor despite current treatments. Targeted therapy in GBM has been the subject of intense investigation but has not been successful in clinical trials. The reasons for the failure of targeted therapy in GBM are multifold and include a lack of patient selection in trials, the failure to identify driver mutations, and poor blood-brain barrier penetration of investigational drugs. Here, we describe a case of a durable complete response in a newly diagnosed patient with GBM with leptomeningeal dissemination and PTPRZ1-MET fusion who was treated with tepotinib, a brain-penetrant MET inhibitor. This case of successful targeted therapy in a patient with GBM demonstrates that early molecular testing, identification of driver molecular alterations, and treatment with brain-penetrant small molecule inhibitors have the potential to change the outcome in select patients with GBM.

Hypofractionated radiotherapy for glioblastoma: A large institutional retrospective assessment of 2 approaches.

Background: Glioblastoma (GBM) poses therapeutic challenges due to its aggressive nature, particularly for patients with poor functional status and/or advanced disease. Hypofractionated radiotherapy (RT) regimens have demonstrated comparable disease outcomes for this population while allowing treatment to be completed more quickly. Here, we report our institutional outcomes of patients treated with 2 hypofractionated RT regimens: 40 Gy/15fx (3w-RT) and 50 Gy/20fx (4w-RT). Methods: A single-institution retrospective analysis was conducted of 127 GBM patients who underwent 3w-RT or 4w-RT. Patient characteristics, treatment regimens, and outcomes were analyzed. Univariate and multivariable Cox regression models were used to estimate progression-free survival (PFS) and overall survival (OS). The impact of chemotherapy and RT schedule was explored through subgroup analyses. Results: Median OS for the entire cohort was 7.7 months. There were no significant differences in PFS or OS between 3w-RT and 4w-RT groups overall. Receipt and timing of temozolomide (TMZ) emerged as the variable most strongly associated with survival, with patients receiving adjuvant-only or concurrent and adjuvant TMZ having significantly improved PFS and OS (P < .001). In a subgroup analysis of patients that did not receive TMZ, patients in the 4w-RT group demonstrated a trend toward improved OS as compared to the 3w-RT group (P = .12). Conclusions: This study demonstrates comparable survival outcomes between 3w-RT and 4w-RT regimens in GBM patients. Receipt and timing of TMZ were strongly associated with survival outcomes. The potential benefit of dose-escalated hypofractionation for patients not receiving chemotherapy warrants further investigation and emphasizes the importance of personalized treatment approaches.

Response of treatment-naive brain metastases to stereotactic radiosurgery.

With improvements in survival for patients with metastatic cancer, long-term local control of brain metastases has become an increasingly important clinical priority. While consensus guidelines recommend surgery followed by stereotactic radiosurgery (SRS) for lesions >3 cm, smaller lesions (≤3 cm) treated with SRS alone elicit variable responses. To determine factors influencing this variable response to SRS, we analyzed outcomes of brain metastases ≤3 cm diameter in patients with no prior systemic therapy treated with frame-based single-fraction SRS. Following SRS, 259 out of 1733 (15%) treated lesions demonstrated MRI findings concerning for local treatment failure (LTF), of which 202 /1733 (12%) demonstrated LTF and 54/1733 (3%) had an adverse radiation effect. Multivariate analysis demonstrated tumor size (>1.5 cm) and melanoma histology were associated with higher LTF rates. Our results demonstrate that brain metastases ≤3 cm are not uniformly responsive to SRS and suggest that prospective studies to evaluate the effect of SRS alone or in combination with surgery on brain metastases ≤3 cm matched by tumor size and histology are warranted. These studies will help establish multi-disciplinary treatment guidelines that improve local control while minimizing radiation necrosis during treatment of brain metastasis ≤3 cm.

Additive Value of MR Simulation Prior to Chemoradiation in Evaluating Treatment Response and Pseudoprogression in High-Grade Gliomas.

BACKGROUND: A dedicated MRI Simulation(MRsim) for radiation treatment(RT) planning in high-grade glioma(HGG) patients can detect early radiological changes, including tumor progression after surgery and before standard of care chemoradiation. This study aimed to determine the impact of using post-op MRI vs. MRsim as the baseline for response assessment and reporting pseudo-progression on follow-up imaging at one month(FU1) after chemoradiation. METHODS: Histologically confirmed HGG patients were planned for six weeks of RT in a prospective study for adaptive RT planning. All patients underwent post-op MRI, MRsim, and follow-up MRI scans every 2-3 months. Tumor response was assessed by three independent blinded reviewers using Response Assessment in Neuro-Oncology(RANO) criteria when baseline was either post-op MRI or MRsim. Interobserver agreement was calculated using light's kappa. RESULTS: 30 patients (median age 60.5 years; IQR 54.5-66.3) were included. Median interval between surgery and RT was 34 days (IQR 27-41). Response assessment at FU1 differed in 17 patients (57%) when the baseline was post-op MRI vs. MRsim, including true progression vs. partial response(PR) or stable disease(SD) in 11 (37%) and SD vs. PR in 6 (20%) patients. True progression was reported in 19 patients (63.3%) on FU1 when the baseline was post-op MRI vs 8 patients (26.7%) when the baseline was MRsim (p=.004). Pseudo-progression was observed at FU1 in 12 (40%) vs. 4 (13%) patients, when the baseline was post-op MRI vs. MRsim (p=.019). Interobserver agreement between observers was moderate (κ = 0.579; p<0.001). CONCLUSIONS: Our study demonstrates the value of acquiring an updated MR closer to RT in patients with HGG to improve response assessment, and accuracy in evaluation of pseudo-progression even at the early time point of first follow-up after RT. Earlier identification of patients with true progression would enable more timely salvage treatments including potential clinical trial enrolment to improve patient outcomes.

A phase II clinical trial of frameless, fractionated stereotactic radiation therapy for brain metastases.

Stereotactic radiation therapy yields high rates of local control for brain metastases, but patients in rural or suburban areas face geographic and socioeconomic barriers to its access. We conducted a phase II clinical trial of frameless, fractionated stereotactic radiation therapy for brain metastases in an integrated academic satellite network for patients 18 years of age or older with 4 or fewer brain metastases. Dose was based on gross tumor volume: less than 3.0 cm, 27 Gy in 3 fractions and 3.0 to 3.9 cm, 30 Gy in 5 fractions. Median follow-up was 10 months for 73 evaluable patients, with a median age of 68 years. Median intracranial progression-free survival was 7.1 months (95% confidence interval = 5.3 to not reached), and median survival was 7.2 months (95% confidence interval = 5.4 to not reached); there were no serious adverse events. Outcomes of this trial compare favorably with contemporary trials, and this treatment strategy provides opportunities to expand stereotactic radiation therapy access to underserved populations.

Advances in the management of spinal metastases: what the radiologist needs to know.

Spine is the most frequently involved site of osseous metastases. With improved disease-specific survival in patients with Stage IV cancer, durability of local disease control has become an important goal for treatment of spinal metastases. Herein, we review the multidisciplinary management of spine metastases, including conventional external beam radiation therapy, spine stereotactic radiosurgery, and minimally invasive and open surgical treatment options. We also present a simplified framework for management of spinal metastases used at The University of Texas MD Anderson Cancer Center, focusing on the important decision points where the radiologist can contribute.

Use of the Toxicity Index in Evaluating Adverse Events in Anal Cancer Trials: Analysis of RTOG 9811 and RTOG 0529.

Novel toxicity metrics that account for all adverse event (AE) grades and the frequency of may enhance toxicity reporting in clinical trials. The Toxicity Index (TI) accounts for all AE grades and frequencies for categories of interest. We evaluate the feasibility of using the TI methodology in 2 prospective anal cancer trials and to evaluate whether more conformal radiation (using Intensity Modulated Radiation Therapy) results in improved toxicity as measured by the TI. Patients enrolled on NRG/RTOG 0529 or nonconformal RT enrolled on the 5-Fluorouracil/Mitomycin arm of NRG/RTOG 9811 were compared using the TI. Patients treated on NRG/RTOG 0529 had lower median TI compared with patients treated with nonconformal RT on NRG/RTOG 9811 for combined GI/GU/Heme/Derm events (3.935 vs 3.996, P=0.014). The TI methodology is a feasible method to assess all AEs of interest and may be useful as a composite metric for future efforts aimed at treatment de-escalation or escalation.

Comparison of setup accuracy and efficiency between the Klarity system and BodyFIX system for spine stereotactic body radiation therapy.

BACKGROUND: Spine stereotactic body radiation therapy (SBRT) uses highly conformal dose distributions and sharp dose gradients to cover targets in proximity to the spinal cord or cauda equina, which requires precise patient positioning and immobilization to deliver safe treatments. AIMS: Given some limitations with the BodyFIX system in our practice, we sought to evaluate the accuracy and efficiency of the Klarity SBRT patient immobilization system in comparison to the BodyFIX system. METHODS: Twenty-three patients with 26 metastatic spinal lesions (78 fractions) were enrolled in this prospective observational study with one of two systems - BodyFIX (n = 11) or Klarity (n = 12). All patients were initially set up to external marks and positioned to match bony anatomy on ExacTrac images. Table corrections given by ExacTrac during setup and intrafractional monitoring and deviations from pre- and posttreatment CBCT images were analyzed. RESULTS: For initial setup accuracy, the Klarity system showed larger differences between initial skin mark alignment and the first bony alignment on ExacTrac than BodyFIX, especially in the vertical (mean [SD] of 5.7 mm [4.1 mm] for Klarity vs. 1.9 mm [1.7 mm] for BodyFIX, p-value < 0.01) and lateral (5.4 mm [5.1 mm] for Klarity vs. 3.2 mm [3.2 mm] for BodyFIX, p-value 0.02) directions. For set-up stability, no significant differences (all p-values > 0.05) were observed in the maximum magnitude of positional deviations between the two systems. For setup efficiency, Klarity system achieved desired bony alignment with similar number of setup images and similar setup time (14.4 min vs. 15.8 min, p-value = 0.41). For geometric uncertainty, systematic and random errors were found to be slightly less with Klarity than with BodyFIX based on an analytical calculation. CONCLUSION: With image-guided correction of initial alignment by external marks, the Klarity system can provide accurate and efficient patient immobilization. It can be a promising alternative to the BodyFIX system for spine SBRT while providing potential workflow benefits depending on one's practice environment.

Multidisciplinary management of spinal metastases: what the radiologist needs to know.

The modern management of spinal metastases requires a multidisciplinary approach that includes radiation oncologists, surgeons, medical oncologists, and diagnostic and interventional radiologists. The diagnostic radiologist can play an important role in the multidisciplinary team and help guide assessment of disease and selection of appropriate therapy. The assessment of spine metastases is best performed on MRI, but imaging from other modalities is often needed. We provide a review of the clinical and imaging features that are needed by the multidisciplinary team caring for patients with spine metastases and stress the importance of the spine radiologist taking responsibility for synthesizing imaging features across multiple modalities to provide a report that advances patient care.

An interdisciplinary consensus on the management of brain metastases in patients with renal cell carcinoma.

Brain metastases are a challenging manifestation of renal cell carcinoma. We have a limited understanding of brain metastasis tumor and immune biology, drivers of resistance to systemic treatment, and their overall poor prognosis. Current data support a multimodal treatment strategy with radiation treatment and/or surgery. Nonetheless, the optimal approach for the management of brain metastases from renal cell carcinoma remains unclear. To improve patient care, the authors sought to standardize practical management strategies. They performed an unstructured literature review and elaborated on the current management strategies through an international group of experts from different disciplines assembled via the network of the International Kidney Cancer Coalition. Experts from different disciplines were administered a survey to answer questions related to current challenges and unmet patient needs. On the basis of the integrated approach of literature review and survey study results, the authors built algorithms for the management of single and multiple brain metastases in patients with renal cell carcinoma. The literature review, consensus statements, and algorithms presented in this report can serve as a framework guiding treatment decisions for patients. CA Cancer J Clin. 2022;72:454-489.

Long term cost comparisons of radical cystectomy versus trimodal therapy for muscle-invasive bladder cancer.

BACKGROUND: Earlier studies on the cost of muscle-invasive bladder cancer treatments are limited to short-term costs of care. We determined the 2- and 5-year costs associated with trimodal therapy (TMT) vs. radical cystectomy (RC). METHODS: We performed a retrospective cohort study using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Total Medicare costs at 2 and 5 years following RC vs. TMT were compared using inverse probability of treatment-weighted propensity score models. RESULTS: A total of 2,537 patients aged 66 to 85 years were diagnosed with clinical stage T2-4a muscle-invasive bladder cancer. Total median costs for patients that received no definitive treatment(s) were $73,780 and $88,275 at 2-and 5-years. Costs were significantly higher for TMT than RC at 2-years ($372,839 vs. $191,363, Median Difference $127,815, Hodges-Lehmann Estimate (H-L) 95% Confidence Interval (CI), $112,663-$142,966) and 5-years ($424,570 vs. $253,651, Median Difference $124,466, H-L 95% CI, $105,711-$143,221). TMT had higher outpatient costs than RC (2-years: $318,221 vs. $100,900; 5-years: $367,092 vs. $146,561) with significantly higher costs with radiology, medications, pathology/laboratory, and other professional services. RC had higher inpatient costs than TMT (2-years: $62,240 vs. $33,631, Median Difference $-29,174, H-L 95% CI, $-32,364-$-25,984; 5-years: $75,499 vs. $45,223, Median Difference $-29,843, H-L 95% CI, $-33,905-$-25,781). CONCLUSIONS AND RELEVANCE: The excess spending associated with trimodal therapy vs. radical cystectomy was largely driven by outpatient expenditures. The relatively high long-term trimodal therapy costs are prime targets for cost containment strategies to optimize future value-based care.

Comparing Costs of Radical Versus Partial Cystectomy for Patients Diagnosed With Localized Muscle-Invasive Bladder Cancer: Understanding the Value of Surgical Care.

OBJECTIVE: To compare costs associated with radical versus partial cystectomy. Prior studies noted substantial costs associated with radical cystectomy, however, they lack surgical comparison to partial cystectomy. METHODS: A total of 2305 patients aged 66-85 years diagnosed with clinical stage T2-4a muscle-invasive bladder cancer from January 1, 2002 to December 31, 2011 were included. Total Medicare costs within 1 year of diagnosis following radical versus partial cystectomy were compared using inverse probability of treatment-weighted propensity score models. Cox regression and competing risks analysis were used to determine overall and cancer-specific survival, respectively. RESULTS: Median total costs were not significantly different for radical than partial cystectomy in 90 days ($73,907 vs $65,721; median difference $16,796, 95% CI $10,038-$23,558), 180 days ($113,288 vs $82,840; median difference $36,369, 95% CI $25,744-$47,392), and 365 days ($143,831 vs $107,359; median difference $34,628, 95% CI $17,819-$53,558), respectively. Hospitalization, surgery, pathology/laboratory, pharmacy, and skilled nursing facility costs contributed largely to costs associated with either treatment. Patients who underwent partial cystectomy had similar overall survival but had worse cancer-specific survival (Hazard Ratio 1.45, 95% Confidence Interval, 1.34-1.58, P < .001) than patients who underwent radical cystectomy. CONCLUSION: While treatments for bladder cancer are associated with substantial costs, we showed radical cystectomy had comparable total costs when compared to partial cystectomy among patients with muscle-invasive bladder cancer. However, partial cystectomy resulted in worse cancer-specific survival further supporting radical cystectomy as a high-value surgical procedure for muscle-invasive bladder cancer.

Long-Term Institutional Experience With Telemedicine Services for Radiation Oncology: A Potential Model for Long-Term Utilization.

PURPOSE: With the development of the coronavirus disease 2019 (COVID-19) pandemic, health care practices and radiation oncology departments have begun to incorporate telemedicine services to practice social distancing and minimize the chances of disease spread. Given the severity of this pandemic, it will likely fundamentally affect the use of these services for years to come. Our institution and radiation oncology department have used telemedicine services for many years; we would like to report on our departmental experience to guide other radiation oncology practices on its long-term use for clinical evaluation and patient care. METHODS AND MATERIALS: Our institution's telemedicine program provides clinical services for a number of remote locations and represents the largest telehealth network in the world, with over 300 sites and 60,000 patient encounters a year. RESULTS: Specifically for our radiation oncology department, over 200 patient encounters occur via telemedicine a year. Patients report great appreciation and satisfaction with these encounters, as they eliminate the time and energy needed for travel from long distances. It has resulted in improved efficiency and cost-effectiveness as well. CONCLUSIONS: Based on our institutional experience, our long-term vision for telemedicine (after COVID-19 pandemic has hopefully subsided) is as an excellent and cost-efficient tool to provide long-term follow-up for patients, especially for those who live far away in rural or underserved areas.

Comparison of Costs of Radical Cystectomy vs Trimodal Therapy for Patients With Localized Muscle-Invasive Bladder Cancer.

Importance: Earlier studies on the cost of muscle-invasive bladder cancer treatments lack granularity and are limited to 180 days. Objective: To compare the 1-year costs associated with trimodal therapy vs radical cystectomy, accounting for survival and intensity effects on total costs. Design, Setting, and Participants: This population-based cohort study used the US Surveillance, Epidemiology, and End Results-Medicare database and included 2963 patients aged 66 to 85 years who had received a diagnosis of clinical stage T2 to T4a muscle-invasive bladder cancer from January 1, 2002, through December 31, 2011. The data analysis was performed from March 5, 2018, through December 4, 2018. Main Outcomes and Measures: Total Medicare costs within 1 year of diagnosis following radical cystectomy vs trimodal therapy were compared using inverse probability of treatment-weighted propensity score models that included a 2-part estimator to account for intrinsic selection bias. Results: Of 2963 participants, 1030 (34.8%) were women, 2591 (87.4%) were white, 129 (4.4%) were African American, and 98 (3.3%) were Hispanic. Median costs were significantly higher for trimodal therapy than radical cystectomy in 90 days ($83 754 vs $68 692; median difference, $11 805; 95% CI, $7745-$15 864), 180 days ($187 162 vs $109 078; median difference, $62 370; 95% CI, $55 581-$69 160), and 365 days ($289 142 vs $148 757; median difference, $109 027; 95% CI, $98 692-$119 363), respectively. Outpatient care, radiology, medication expenses, and pathology/laboratory costs contributed largely to the higher costs associated with trimodal therapy. On inverse probability of treatment-weighted adjusted analyses, patients undergoing trimodal therapy had $136 935 (95% CI, $122 131-$152 115) higher mean costs compared with radical cystectomy 1 year after diagnosis. Conclusions and Relevance: Compared with radical cystectomy, trimodal therapy was associated with higher costs among patients with muscle-invasive bladder cancer. The differences in costs were largely attributed to medication and radiology expenses associated with trimodal therapy. Extrapolating cost figures resulted in a nationwide excess spending of $468 million for trimodal therapy compared with radical cystectomy for patients who received a diagnosis of bladder cancer in 2017.

The Use of "QUAD Shot" in Anal Canal Squamous Cell Carcinoma: A Case Study With Review of the Literature.

CONTEXT: Patients with locoregional anal carcinoma who do not qualify for standard definitive chemoradiation are candidates for a short course of palliative hypofractionated radiotherapy such as QUAD Shot. METHODS: A 57-year-old man with massive locoregional squamous cell carcinoma of the anal canal was treated with QUAD Shot (14.8 Gy in four fractions over two consecutive days) repeated every four weeks for a total of two courses. RESULTS: He reported symptomatic relief following each course of radiation. In regard to his first QUAD Shot, his pain was 10/10 in severity at the time of admission and 4/10 at the time of discharge. In regard to his second QUAD Shot, his pain was 8/10 at the time of admission and 0/10 at the time of discharge. He did not experience any treatment-related toxicity. He passed away 15 weeks after the first course. CONCLUSION: QUAD Shot is both efficacious and safe for palliation in patients with anal carcinoma.

Can tibial tantalum cones eventually eliminate the adjuvant use of metallic augments for AORI type 2B/3 metaphyseal defects??-A novel surgical technique and case series.

BACKGROUND: For extensive metaphyseal defects, the use of tantalum cones is usually combined with adjuvant stems which may be cemented/cementless and metallic bone augments for additional stability. A Tibial baseplate-Cone construct with proud tibial cones and without metallic augments has been described for AORI type 2B/3 tibial defects. METHODS: A case series analysis of 6 patients with AORI type 3 defects treated with unstepped proud Tantalum tibial metaphyseal cones without metallic wedges/full width augments. A follow-up analysis done with clinico-radiographic interpretation. RESULTS: 100% osteointegration noted in final radiographs of all patients at an average follow-up of 4.1 years. Preoperative average ROM/KSS of 75/49 improved to postoperative ROM/KSS of 104/79. Outcomes were interpreted as excellent in 50% of cases and good in the remaining 50%. CONCLUSION: The "Tibial base plate-cone without augments (BCCA)"type of a construct may offer a valid long term advantage over the Tibial base plate-Augment-Cone combination in massive tibial bone defects. Simply building up the tantalum cone to the native joint line position by increasing cone height can exclude use of augments or wedges.

Comparing Survival Outcomes and Costs Associated With Radical Cystectomy and Trimodal Therapy for Older Adults With Muscle-Invasive Bladder Cancer.

Importance: Radical cystectomy is the guidelines-recommended treatment of muscle-invasive bladder cancer, but a resurgence of trimodal therapy has occurred. Limited comparative data are available on outcomes and costs attributable to these 2 treatments. Objective: To compare the survival outcomes and costs between trimodal therapy and radical cystectomy in older adults with muscle-invasive bladder cancer. Design, Setting, and Participants: This population-based cohort study used data from the Surveillance, Epidemiology, and End Results-Medicare linked database. A total of 3200 older adults (aged ≥66 years) with clinical stage T2 to T4a bladder cancer diagnosed from January 1, 2002, to December 31, 2011, and with claims data available through December 31, 2013, were included in the analysis. Patients who received radical cystectomy underwent either only surgery or surgery in combination with radiotherapy or chemotherapy. Patients who received trimodal therapy underwent transurethral resection of the bladder followed by radiotherapy and chemotherapy. Propensity score matching by sociodemographic and clinical characteristics was used. Data analysis was performed from August 1, 2017, to March 11, 2018. Main Outcomes and Measures: Overall survival and cancer-specific survival were evaluated using the Cox proportional hazards regression model and the Fine and Gray competing risk model. All Medicare health care costs for inpatient, outpatient, and physician services within 30, 90, and 180 days of treatment were compared. The total amount spent nationwide was estimated, using 180-day medical costs between treatments, by the total number of new cases of muscle-invasive bladder cancer in the United States in 2011. Results: Of the 3200 patients who met the inclusion criteria, 2048 (64.0%) were men and 1152 (36.0%) were women, with a mean (SD) age of 75.8 (6.0) years. After propensity score matching, 687 patients (21.5%) underwent trimodal therapy and 687 patients (21.5%) underwent radical cystectomy. Patients who underwent trimodal therapy had significantly decreased overall survival (hazard ratio [HR], 1.49; 95% CI, 1.31-1.69) and cancer-specific survival (HR, 1.55; 95% CI, 1.32-1.83). No differences in costs at 30 days were observed between trimodal therapy ($15 233 in 2002 vs $18 743 in 2011) and radical cystectomy ($17 990 in 2002 vs $21 738 in 2011). However, median total costs were significantly higher with trimodal therapy than with radical cystectomy at 90 days ($80 174 vs $69 181; median difference, $8964; Hodges-Lehmann 95% CI, $3848-$14 079) and at 180 days ($179 891 vs $107 017; median difference, $63 771; Hodges-Lehmann 95% CI, $55 512-$72 029). Extrapolating these figures to the total US population revealed $335 million in excess spending for trimodal therapy compared with the less costly radical cystectomy ($492 million) for patients who received a muscle-invasive bladder cancer diagnosis in 2011. Conclusions and Relevance: Trimodal therapy was associated with significantly decreased overall survival and cancer-specific survival as well as $335 million in excess spending in 2011. These findings have important health policy implications regarding the appropriate use of high value-based care among older adults with invasive bladder cancer who are candidates for either radical cystectomy or trimodal therapy.