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Costello, Brian A.

https://orcid.org/0000-0003-1753-5928

Mayo Clinic

Mayo Clinic

Citations 155

NCCN Guidelines® Insights: Kidney Cancer, Version 2.2024
Jonasch, Eric, Alva, Ajjai , Bagshaw, H.P. , Costello, Brian A. , Derweesh, Ithaar , Desai, Arpita, Ged, Yasser , Johnson, Michael P. , King, Jennifer , Kyriakopoulos, Christos E. , Lara, Primo N. , Lau, Clayton, Lewis, Bryan , Mortazavi, Amir , Ponsky, Lee , Ramalingam, Sundhar, Shuch, Brian , Smith, Zachary L. , Sosman, Jeffrey A. , Zibelman, Matthew R. , Schonfeld, Ryan, Stein, MaryElizabeth , Gurski, Lisa A., Motzer, Robert J. , Agarwal, Neeraj , Baine, Michael J. , Beckermann, Kathryn E. , Carlo, Maria I. , Choueiri, Toni K. , George, Saby , Gore, John L. , Gunn, Andrew, Haas, Naomi B , Johnson, Michael, Kapur, Payal , King, Jennifer, Lam, Elaine T. , Madoff, David C. , Manley, Brandon J. , Michaelson, M. Dror , Sweis, Randy F.

Journal of the National Comprehensive Cancer Network | February 23, 2024 | Volume: 22 | Issue: 1 | Pages: 4-16

10.6004/jnccn.2024.0008 Get It

The NCCN Guidelines for Kidney Cancer provide multidisciplinary recommendations for diagnostic workup, staging, and treatment of patients with renal cell carcinoma (RCC). These NCCN Guidelines Insights focus on the systemic therapy options for patients with advanced RCC and summarize the new clinical data evaluated by the NCCN panel for the recommended therapies in Version 2.2024 of the NCCN Guidelines for Kidney Cancer.
Development and validation of a novel prognostic model for disease-specific survival in patients with non-metastatic small cell carcinoma of the bladder.
Lewis, Akeem Ronell, Kase, Adam M. , Tyson, Mark D. , Boorjian, Stephen A. , Pagliaro, Lance C. , Costello, Brian A. , Orme, Jacob J. , Diamantopoulos, Leonidas Nikolaos , Childs, Daniel S. , Lucien, Fabrice , Basourakos, Spyridon P. , Singh, Parminder Pal

Journal of Clinical Oncology | January 29, 2024 | Volume: 42 | Issue: 4_suppl | Pages: 695-695

10.1200/jco.2024.42.4_suppl.695 Get It

695 Background: Small cell carcinoma of the bladder (SCCB) is a rare variant of bladder cancer with limited data informing prognosis. We present a novel prognostic model for disease specific survival (DSS) for patients with non-metastatic (M0) SCCB, derived from the Surveillance, Epidemiology and End Results (SEER) database. Methods: The SEER database (18 registries/November 2020) was queried with the ICD-10 topography codes C67.0-C67.9 (bladder), and the morphologic code 8041 (SCCB). Eligible patients (adults, histologic confirmation, available follow-up/staging data, M0) were randomly divided into a training (TC) and a validation cohort (VC) (7:3 ratio). Variables significantly associated with DSS were identified with multivariate Cox regression and backwards stepwise conditional approach and inserted in the model. Points were assigned to each variable based on the formula: Probability of an event at time t=S0(t)exp(β1x1, β2x2...), (β = regression coefficients, x = observed covariate values, S0(t) = survival function). Cumulative risk points were assigned to each patient and three distinct risk categories for DSS were constructed. Harrel’s C-statistic with bootstrap resampling was used for internal (TC) and external (VC) validation. Model performance was compared to the AJCC 8th edition (likelihood ratio test -LRT). Results: A total of 1039 patients were included (739 TC, 300 VC). No statistically significant differences in baseline characteristics/survival outcomes were identified between TC and VC. Age (years), T/N stage, radical cystectomy, chemotherapy, and radiation were significant variables inserted in the multivariate model (table). Patients were stratified to three risk groups (low, intermediate, high) based on the total cumulative risk points collected. Median DSS was NR (95%CI; NR, NR), 25 (95% CI; 18-32) and 9 months (95% CI; 7-11) for the low, intermediate, and high-risk category, log-rank p<.001. Harrel's C-statistic for the model was 0.70 (95%CI;0.67-0.73) in the TC and 0.66 (95%CI; 0.61-0.71) in the VC. In comparison, C-statistic for the AJCC 8th edition was 0.56 (95% CI; 0.52-0.59) and 0.53 (95% CI; 0.51 to 0.57), respectively. The LRT demonstrated superior performance of the model compared to AJCC (p<.001). Conclusions: We present a novel prognostic model for DSS in patients with locoregional SCCB composed of variables readily available in daily practice, which may serve as a useful tool for individualized risk assessment of patients with this rare malignancy. Further validation in prospective studies/clinical trials is warranted. [Table: see text]
Health-related quality of life (HrQoL) of first-line treatments in metastatic renal cell carcinoma (mRCC): A network meta-analysis.
Naqvi, Syed Arsalan Ahmed , Faisal, Kunwer Sufyan , Imran, Manal , Khakwani, Kaneez Zahra Rubab, Raina, Ammad, Tripathi, Nikita , Abdul‐Muhsin, Haidar , Costello, Brian A. , Abidoye, Oluseyi , Singh, Parminder Pal , Bryce, Alan H. , Riaz, Irbaz Bin

Journal of Clinical Oncology | January 29, 2024 | Volume: 42 | Issue: 4_suppl | Pages: 412-412

10.1200/jco.2024.42.4_suppl.412 Get It

412 Background: Previously we have reported comparative effectiveness data regarding survival of first line (1L) treatment options in mRCC. However, it is not known how the life-prolonging frontline combinations compare to patient-reported outcomes. Methods: Electronic databases including MEDLINE and EMBASE were searched from each database’s inception through July 1st 2023. Phase III randomized controlled trials (RCTs) assessing 1L immune-checkpoint inhibitor (ICI) combination therapies for mRCC and reporting HrQoL were included. Small sample size adjusted standardized mean differences (SMD; Hedges’ g) with 95% confidence intervals (CI) were computed for global, physical, functional, and emotional QoL. Positive SMD indicated an improvement. A network meta-analysis was conducted to assess the comparative HrQoL across different treatment options. P-scores were computed to assess relative treatment rankings. Results: Of 5770 citations identified, five trials (nine references) were included in this analysis. Patient-reported outcomes have not been reported in the JAVELIN Renal 101 or COSMIC-313 trials yet. Global QoL was significantly improved with cabozantinib-nivolumab (CaboNivo) as compared to Nivo-ipilimumab (SMD 2.74, 95% CI 2.54; 2.93), lenvatinib-pembrolizumab (LenPem; 2.79, 2.53; 3.06), sunitinib (2.87, 2.72; 3.03), Pem-axitinib (PemAxi; 3.09, 2.89; 3.30) and atezolizumab-bevacizumab (AteBev; 3.24, 3.04; 3.45). Global QoL improvement was also observed with NivoIpi compared to sunitinib (0.14, 0.02; 0.25), PemAxi (0.36, 0.18; 0.54) and AteBev (0.51, 0.33; 0.68). Physical QoL improvement were consistent with CaboNivo. Likewise, LenPem significantly improved QoL compared to sunitinib (0.26, 0.04; 0.47), PemAxi (0.38, 0.13; 0.64) and NivoIpi (0.51, 0.27; 0.76). Significant functional QoL benefits were only observed with CaboNivo (0.32, 0.17; 0.48) and NivoIpi (0.19, 0.08; 0.31) compared to sunitinib. No significant mixed treatment comparisons were observed for emotional QoL, however, currently available data suggests that LenPem (rank 1) may potentially improve QoL (Table). Conclusions: CaboNivo and NivoIpi as 1L therapy may offer an improved overall HrQoL compared to other contemporary treatment options in mRCC. [Table: see text]
Preliminary analysis of baseline characteristics, patient reported outcomes (PROs), and treatment selection in ODYSSEY.
Ged, Yasser , Alva, Ajjai , Costello, Brian A. , Maughan, Benjamin L. , Kilari, Deepak , Jabusch, Sarah , Ward, Kimberly T., Wulff‐Burchfield, Elizabeth , Zhang, Tian , George, Daniel J. , Harrison, Michael R. , Bhavsar, Nrupen Anjan , Zakharia, Yousef , Wong, Risa Liang , Page, Courtney B , Troy, Jesse D , Scales, Charles D. , George, Daniel J.

Journal of Clinical Oncology | January 29, 2024 | Volume: 42 | Issue: 4_suppl | Pages: 385-385

10.1200/jco.2024.42.4_suppl.385 Get It

385 Background: Tyrosine kinase inhibitors (TKI) and immuno-oncology (IO) agents alone or in combination have revolutionized the landscape of management for untreated metastatic renal cell carcinoma (mRCC). Baseline quality of life (QOL) outside of interventional clinical trials and rationale for management decisions in mRCC are poorly understood. Methods: In this prospective observational study of 800 mRCC pts in the US, pts must: have a diagnosis of mRCC (any histology) with no prior systemic therapy (ST) for mRCC; be age ≥19 at informed consent; be able to comply with completion of PROs. Exclusion criteria include being treated for active malignancy other than mRCC or not intending to follow up at a study site within PCORnet. Pts undergo consent and baseline assessments by the study site team, with subsequent follow up by the central coordinating center. The primary objective is to determine distinct patterns of change in QOL and symptom burden of mRCC pts. A key secondary objective is to identify patterns of clinical management in the real world setting of mRCC across treatment regimens. Minimally important differences are defined as 3- and 7-points for FKSI-19 and FACT-G respectively. ClinicalTrials.gov ID: NCT04919122. Results: As of 9/1/2023, 173 pts have been enrolled (126 ST, 47 no ST [NST]): 75% male, 87% white, 73% clear cell, 52% intermediate risk and 47% poor risk. 47% had radical nephrectomy and 22% another solid tumor. ST pts as compared to NST pts were more likely to be poor risk (52% vs 16%); but differences in baseline pain were not significant. Of ST pts, 44 were treated with IO-IO (ipilimumab + nivolumab), 50 with IO-TKI (cabozantinib + nivolumab 38%, axitinib + pembrolizumab 38%, lenvatinib + pembrolizumab 24%) and 32 other (IO alone 34%, TKI alone 31%, investigational drug 25%). Reasons for NST included active surveillance (AS, 50%), other (21%), local therapy (13%). Mean differences between ST and NST for baseline FKSI-19 and FACT-G were 5.7 (95% CI: 1.2 – 10.2) and 3.3 (-2.6 – 9.3). There were no differences in pain or PROs between IO-IO and IO-TKI pts. Mean differences in FKSI-19 and FACT-G between AS vs IO-IO were 10.6 (4.8 – 16.4) and 8.6 (1.1 – 16.0); and vs IO-TKI were 11.0 (4.9 – 17.0) and 10.3 (3.5 – 17.1). On physician surveys, primary reasons for treatment selection were (in order of % selected): complete response (CR), prolonged survival (OS), prognostic factors (Px), treatment-free interval for IO-IO; versus delaying progression (PFS), OS, CR, Px for IO-TKI. Conclusions: Our data suggest differences in baseline QoL in pts treated with ST vs NST, as well as AS vs IO-IO or IO-TKI, in the real world. Reasons for selection of ST regimen differed among combination regimen classes. Completion of ODYSSEY will clarify baseline and longitudinal differences in pain and PROs among management strategies and give novel insights into the rationale for real world management of untreated pts with mRCC. Clinical trial information: NCT04919122 .
Venous tumor thrombus destinations in patients with renal cell carcinoma.
Pessoa, Rodrigo Rodrigues , Cheville, John C. , Lohse, Christine M. , Costello, Brian A. , Thompson, Houston R., Boorjian, Stephen A. , Leibovich, Bradley C. , Sharma, Vidit , Nabavizadeh, Reza , Lucien, Fabrice , Thompson, Houston

Journal of Clinical Oncology | January 29, 2024 | Volume: 42 | Issue: 4_suppl | Pages: 381-381

10.1200/jco.2024.42.4_suppl.381 Get It

381 Background: Venous tumor thrombus (VTT) is associated with worse oncologic outcomes in clear cell renal cell carcinoma (ccRCC). It is unknown if VTT and pulmonary embolism (PE) predispose patients to pulmonary metastasis. Methods: We queried our institutional registry for ccRCC patients undergoing radical nephrectomy (1970-2019). Cox proportional hazards regression models, adjusting for factors associated with ccRCC progression, were used to determine if VTT and PE were associated with pulmonary metastasis. Results: Of 3,410 patients studied, 1,025 (30%) had VTT, and patients with VTT were more likely to present with pulmonary metastasis at nephrectomy (20% vs 7%, p<0.001). Within the VTT subset, level of VTT was not significantly associated with pulmonary metastasis at nephrectomy (p=0.3). For all patients who had metastatic disease at nephrectomy (n=643), pulmonary metastasis was more common in those with VTT versus those without VTT (68% vs 51%, p<0.001). Excluding patients with pulmonary metastasis at nephrectomy, on multivariable analysis, VTT remained associated with post-nephrectomy pulmonary metastasis (hazard ratio (HR) 1.31, p<0.001) without a notable difference in HRs between renal vein (1.27) and caval (1.38) VTT. Presence of PE in the setting of VTT was associated with increased pulmonary metastasis post-nephrectomy (HR 2.31, p<0.001). Conclusions: VTT is associated with disproportionately increased pulmonary metastasis at presentation and post-nephrectomy in ccRCC patients. Further, the presence of PE at nephrectomy for VTT was associated with increased pulmonary metastasis post-nephrectomy. These results support a metastatic predilection of ccRCC with VTT to the lungs.
Phase 1 trial of navitoclax and sorafenib in patients with refractory solid tumors with a hepatocellular carcinoma expansion cohort.
Emiloju, Oluwadunni Eunice, Yin, Jun , Koubek, Emily J. , Lou, Yanyan , Seetharam, ­Mahesh , Edelman, Martin Joseph, Jiang, Yixing , Posey, James , Davis, S. Lindsey , Roberts, Lewis R. , Takebe, Naoko , Hendrickson, Andrea E. Wahner , Costello, Brian A. , Roberts, Lewis R , Reid, Joel M. , Borad, Mitesh J. , Edelman, Martin J. , Kaseb, Ahmed O , Gores, Gregory J. , Kaufmann, Scott H. , Hubbard, Joleen M.

Journal of Clinical Oncology | January 22, 2024 | Volume: 42 | Issue: 3_suppl | Pages: 507-507

10.1200/jco.2024.42.3_suppl.507 Get It

507 Background: Navitoclax (ABT-263) is an oral Bcl-2 homology-3 mimetic that binds with high affinity to pro-survival Bcl-2 proteins, resulting in apoptosis. Sorafenib, an oral multi kinase inhibitor inhibits tumor angiogenesis and also promotes apoptosis. The efficacy of either agent alone is limited; however, preclinical studies demonstrate synergy with the combination of navitoclax and sorafenib. Methods: In this phase 1 pharmacokinetic and pharmacodynamic study (NCT01364051), we evaluated the combination of navitoclax and sorafenib in a dose escalation cohort of patients with refractory solid tumors, with an expansion cohort in hepatocellular carcinoma (HCC). The study agents were provided by the Cancer Therapy Evaluation Program at National Cancer Institute under CRADA. Navitoclax and sorafenib were administered continuously on days 1 through 21 of 21-day cycles. The maximum tolerated dose (MTD) was determined using the continual reassessment method. Results: Ten patients were enrolled in the dose escalation cohort and 15 patients with HCC were enrolled in the expansion cohort. Two dose levels were tested, dose level 1 (navitoclax 150 mg daily plus sorafenib 400 mg twice daily) and dose level 2 (navitoclax 200 mg daily plus sorafenib 400 mg twice daily). At dose level 1, one dose limiting toxicity (DLT) [grade 3 aspartate aminotransferase elevation] was observed among 6 patients treated at this dose level. In a cohort of 3 patients treated at dose level 2, two DLTs were observed (grade 3 hypertension, and grade 3 rash), hence dose level 1 was identified as the MTD. Among all patients, the most common grade 3 toxicity was thrombocytopenia (5 patients, 20%): there were no grade 4 or 5 toxicities (Table). Patients received a median of 2 cycles (range 1-36 cycles) and all patients were off study treatment at data cut off. Six patients in the expansion cohort had stable disease, 5 had progressive disease and 4 with unavailable data. There were no partial or complete responses. Drug-drug interaction between navitoclax and sorafenib was not observed. The combination of navitoclax and sorafenib did not increase induction of apoptosis compared with navitoclax alone. Conclusions: Navitoclax plus sorafenib resulted in manageable, but not ideal toxicities for continuous oral administration which precluded dose escalation. The lack of clinical benefit in the HCC expansion cohort does not support further development of this combination for the treatment of advanced HCC. Clinical trial information: NCT01364051 . [Table: see text]
Emerging Antibody-Drug Conjugate Therapies and Targets for Metastatic Renal Cell Carcinoma
Gottlich, Harrison C., Pessoa, Rodrigo Rodrigues , Mahmoud, Ahmed , Garg, I. D. , Orme, Jacob J. , Costello, Brian A. , Cheville, John C. , Mahmoud, Ahmed M , Nabavizadeh, Reza , Dumbravă, Mihai , Garg, Ishita, Lucien, Fabrice

Kidney Cancer | December 29, 2023 | Volume: 7 | Issue: 1 | Pages: 161-172

10.3233/kca-230012 Get It

Background: Approximately 30% of renal cell carcinoma (RCC) cases present with de novo metastatic disease, while 20% to 30% of those with localized disease will develop metastases following surgical resection. Various drug classes have been investigated to treat RCC, including cytokine-based therapies, small molecule Vascular Endothelial Growth Factor (VEGF) tyrosine kinase inhibitors (TKIs) and antibody-based therapies. Up to 58% of patients fail to respond to primary immune checkpoint inhibitor (ICI) therapy, and nearly all initial responders experience disease progression due to the development of secondary resistance. Consequently, novel treatment options are being investigated. Objective: Review the rapidly evolving ADC therapeutic landscape in metastatic RCC including recent trials, emerging ADCs targets, and future directions for ADCs in the treatment of advanced RCC. Methods: Literature review using the MEDLINE database on important trials and presentations from the American Society of Clinical Oncology (ASCO), and the European Society for Medical Oncology (ESMO) conferences. Key words used included “renal cell carcinoma,” “RCC,” “metastatic RCC,” “advanced RCC,” “antibody-based therapies,” “immunotherapy,” “clinical trials,” and “emerging drugs.” Specifically for review of ADCs in RCC, the following search string was used with additional review of bibliographies from retrieved papers: “((antibody drug conjugate) OR (antibody-dependent cellular cytotoxicity) OR (chimeric antigen receptor)) AND ((kidney cancer) OR (renal cell carcinoma))”. Results: Several promising targets including MMP14, EGFR, MCT4, CA9, MET, CDH13, B7-H3, and PSMA were identified with relevant preclinical and clinical studies reviewed. Conclusions: While ADCs therapeutics have not shown benefit to date for renal cell carcinoma, there are ample promising candidates and targets for future research.
Characterizing the Users of Patient Portal Messaging: A Single Institutional Cohort Study
Mastorakos, George , Zhou, Jiawei , Zong, Nansu , Prigge, Julie , Costello, Brian A. , Huang, Ming , Khurana, Aditya , Yu, Yue , Patten, Christi A. , Liu, Hongfang

2023 IEEE 11th International Conference on Healthcare Informatics (ICHI) | December 11, 2023 | Volume: No volume available | Issue: No issue available | Pages: 381-387

10.1109/ichi57859.2023.00057 Get It

Copanlisib in Combination with Nivolumab in Subjects with Relapsed/Refractory Diffuse Large B-Cell Lymphoma and Primary Mediastinal Large B-Cell Lymphoma: A Phase II Study
Atherton, Pamela J. , Steinert, Kimberly O., Narkhede, Mayur , Vaidya, Rakhee , Said, Rabih, Costello, Brian A. , Ansell, Stephen M. , Nowakowski, Grzegorz S. , Bennani, N. Nora , Rimsza, Lisa M. , Tun, Aung M. , Hoffmann, Marc Steven , Shapiro, Geoffrey I.

Blood | December 1, 2023 | Volume: 142 | Issue: Supplement 1 | Pages: 4475-4475

10.1182/blood-2023-190540 Get It

Introduction: Diffuse Large B-cell Lymphoma (DLBCL) are aggressive B-cell non-Hodgkin lymphomas (NHL). One particular subtype, Primary Mediastinal B-cell Lymphoma (PMBCL), is often grouped with DLBCL, but it possesses distinct biological and clinical characteristics. While initial therapy successfully cures approximately two-thirds of patients (pts), those who do not respond or experience progression within the first two years have a poor prognosis despite novel cellular therapies and bispecifics and ultimately succumb to their disease. There is a pressing need for more effective therapeutic approaches in this patient population. Recent advances in the understanding of DLBCL pathogenesis have led to the targeting of various signaling pathways, including the PI3K-AKT-mTOR pathway. One such drug, copanlisib (C), a pan-PI3K inhibitor with potent PI3K-α/PI3K-δ inhibition, exhibited activity in both indolent and aggressive NHL. In preclinical studies using a DLBCL mouse model, treatment with C effectively reduced the immunosuppressive tumor-infiltrating T-regulatory cells (Tregs). Moreover, when combined with a surrogate anti-mouse programmed death -1 (PD-1) blocker, C demonstrated significant in vivo responses (75%) compared to the monotherapy groups (0%). These findings support the rationale for exploring the combination of nivolumab, a PD-1 blocker, and copanlisib (C-N) in DLBCL. Thus, a phase 2 prospective study has been developed, focusing on two relapsed/refractory (RR) cohorts (DLBCL and PMBCL), treated with the combination of C-N. A prespecified interim analysis was planned upon enrollment of 14 pts. Herein, we report outcomes of the 12 enrolled pts, as the study was halted prematurely due to a safety signal deemed possibly related to the combination. Study design: C 60 mg was given intravenously on days 1, 8, and 15 during cycles 1-8, and on days 1 and 15 in subsequent cycles. N 240 mg IV was given on days 1 and 15 during cycles 1-8, and 480 mg on day 1 on subsequent cycles. Each treatment cycle is 28 days. Therapy was given for up to 2 years, as long as there is no disease progression or unacceptable side effects. The primary objective of the study is to determine the ORR, which includes complete and partial responses (CR+PR). Secondary objectives include evaluating the safety of the combination, as well as assessing progression-free survival (PFS), duration of response (DOR), CR, and overall survival (OS). The study plan was to enroll a maximum of 106 pts, including a safety cohort of 6 pts. The study received funding from Bayer and conducted through NCI-CTEP (NCI Protocol #10193; NCT03484819). Results: Twelve pts who received at least one cycle of C-N were included in this analysis. Pt characteristics are illustrated in table 1. All enrolled pts had DLBCL histology. Only one patient received a prior autologous stem cell transplant. Interestingly 4/12 received prior chimeric antigen receptor T-cell therapy (CART). Of the 12 enrolled pts, seven were evaluated for response. The ORR was 25% (3/12) (95% CI: 5 - 57%), all CR. The median number of cycles received was 2.5 (range 1-24) with two pts receiving 23 and 24 cycles. Observed grade 3 and higher adverse events (AEs) were as follows: non-hematologic AEs in 10/12 (83.3%), while hematologic AEs were seen in 5/12 (41.7%) pts. A relatively higher incidence of cardiac events (4/12) were noted including one cardiac arrest after one cycle of therapy, and four atrial fibrillation events, all grade 3, but only two were deemed possibly attributed to therapy. The cardiac arrest was deemed unrelated to therapy. Conclusions: C-N combination had modest clinical activity in pts with R/R DLBCL with some prolonged responses. However, due to the relatively high number of cardiac events and the changing therapeutic landscape with recent approvals, a decision was made to halt the study. These findings likely reflect possibly older and sicker patient population. Biomarker studies for predictors of response are under consideration.
Comparative cost-effectiveness of contemporary treatment strategies for stage IIA seminoma
Sharma, Vidit , Wymer, Kevin , Walia, Arman, Costello, Brian A. , Pagliaro, Lance C. , Daneshmand, Siamak , Leibovich, Bradley C. , Boorjian, Stephen A. , Joyce, Daniel D , Moriarty, James P. , Pagliaro, Lance C , Daneshmand, Siamak , Boorjian, Stephen A , Joyce, Daniel , Borah, Bijan J.

JNCI: Journal of the National Cancer Institute | October 11, 2023 | Volume: 116 | Issue: 3 | Pages: 468-475

10.1093/jnci/djad211 Get It

Abstract Background The Surgery in Early Metastatic Seminoma (SEMS) trial examined retroperitoneal lymph node dissection as first-line treatment for patients with isolated 1-3 cm retroperitoneal lymphadenopathy. To date, the standard of care for these patients has been either chemotherapy or radiotherapy. Herein, we evaluated the relative cost-effectiveness of these management strategies. Methods A microsimulation model assessed the cost-effectiveness of retroperitoneal lymph node dissection, chemotherapy, and radiotherapy for stage IIA seminoma. Sensitivity analyses were performed to evaluate model robustness. Retroperitoneal lymph node dissection recurrence probabilities were obtained from the SEMS trial. All other probability and utility values were obtained from published literature. Primary outcomes included costs from a commercial insurer’s perspective, effectiveness (quality adjusted life-years [QALYs]), and incremental cost-effectiveness ratios using a willingness-to-pay threshold of $100 000/QALY. Results At a lifetime horizon, the mean costs per patient for retroperitoneal lymph node dissection, radiotherapy, and chemotherapy were $58 469, $98 783, and $104 096, and the mean QALYs were 40.61, 40.70, and 39.15, respectively. Retroperitoneal lymph node dissection was found to be the most cost-effective approach because of high costs and accrued disutility of chronic toxicities associated with radiotherapy (cost-effectiveness ratios = $433 845/QALY) and chemotherapy (dominated). On 1-way sensitivity analyses, retroperitoneal lymph node dissection was no longer cost-effective if the probabilities of infertility and cardiovascular toxicity after radiotherapy were less than 13% and 16%, respectively, or if the 2-year probability of progression after retroperitoneal lymph node dissection was more than 26%. Conclusions Retroperitoneal lymph node dissection was the most cost-effective treatment approach for stage IIA seminoma. These findings support clinical guideline consideration of including retroperitoneal lymph node dissection as a treatment option for well-selected patients with stage IIA seminoma.