Radiotherapy Following Chemoimmunotherapy in Extensive- Stage Small Cell Lung Cancer: A Subgroup Analysis of Consolidation Versus Salvage Indications

Radiotherapy Following Chemoimmunotherapy in Extensive- Stage Small Cell Lung Cancer: A Subgroup Analysis of Consolidation Versus Salvage Indications | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Radiotherapy Following Chemoimmunotherapy in Extensive- Stage Small Cell Lung Cancer: A Subgroup Analysis of Consolidation Versus Salvage Indications Dongmei Luo, Liya Wang, Mengyi Zhu, Yang Liu, Jing Lin, Guihong Liu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9345237/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Background Chemo-immunotherapy (CIT) is established as first-line treatment for extensive-stage small cell lung cancer (ES-SCLC), and combining CIT with radiotherapy (RT) holds promise. However, high-level evidence on the efficacy, safety, and distant metastasis impact of this combination remains scarce. This study evaluated the survival benefit and safety of adding local RT to first-line CIT in ES-SCLC. Methods This retrospective study analyzed clinical data from 132 ES-SCLC patients treated with first-line chemoimmunotherapy at our institution between January 2019 and December 2024. Patients were categorized into two groups: the chemoimmunotherapy plus radiotherapy (RT) group (n = 73) and the chemoimmunotherapy-only (non-RT) group (n = 59). Baseline characteristics, tumor response, and treatment-related adverse events (AEs) were compared using Chi-square. Kaplan-Meier analysis and log-rank tests were employed to assess progression-free survival (PFS), primary tumor PFS (PFS-PT), distant metastasis PFS (PFS-DM), and overall survival (OS). Cox proportional hazards models were used for univariate and multivariate analyses. Results The CIT + RT group showed significantly better outcomes. Objective response rate (83.6% vs. 49.2%, P < 0.001) and disease control rate (90.4% vs. 62.7%, P < 0.001) were higher with RT. Median OS (21.0 vs. 13.0 months, HR 0.514, 95% CI 0.331–0.798) and PFS (9.5 vs. 6.0 months, HR 0.552, 95% CI 0.383–0.796) were prolonged. RT also extended median PFS-PT (11.8 vs. 8.0 months, P < 0.001) and PFS-DM (11.8 vs. 7.1 months, P = 0.010). RT was an independent protective factor for OS/PFS. consolidation RT outperformed salvage RT (both P < 0.01). AE incidence (Grade I-II/III-IV) did not differ significantly. Conclusion The addition of local radiotherapy to first-line chemo-immunotherapy significantly improves survival outcomes, including distant metastasis control, in ES-SCLC patients without significantly increasing treatment-related adverse events. Radiotherapy serves as an independent favorable prognostic factor, with consolidation timing being critical for optimal outcomes. Extensive-stage small cell lung cancer First-line treatment Chemotherapy Immunotherapy Radiotherapy Efficacy Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 01 May, 2026 Reviewers agreed at journal 01 May, 2026 Reviewers invited by journal 29 Apr, 2026 Editor invited by journal 08 Apr, 2026 Editor assigned by journal 07 Apr, 2026 Submission checks completed at journal 07 Apr, 2026 First submitted to journal 07 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9345237","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":635252245,"identity":"405e9245-3a93-4290-b9e3-dd0be750481c","order_by":0,"name":"Dongmei Luo","email":"","orcid":"","institution":"Xuzhou Medical College","correspondingAuthor":false,"prefix":"","firstName":"Dongmei","middleName":"","lastName":"Luo","suffix":""},{"id":635252246,"identity":"1c29e5c6-e0ed-49d9-aa32-4629f4eafad4","order_by":1,"name":"Liya Wang","email":"","orcid":"","institution":"Xuzhou Medical 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Indications","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-cancer","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcan","sideBox":"Learn more about [BMC Cancer](http://bmccancer.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcan/default.aspx","title":"BMC Cancer","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Extensive-stage small cell lung cancer, First-line treatment, Chemotherapy, Immunotherapy, Radiotherapy, Efficacy","lastPublishedDoi":"10.21203/rs.3.rs-9345237/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9345237/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eChemo-immunotherapy (CIT) is established as first-line treatment for extensive-stage small cell lung cancer (ES-SCLC), and combining CIT with radiotherapy (RT) holds promise. However, high-level evidence on the efficacy, safety, and distant metastasis impact of this combination remains scarce. This study evaluated the survival benefit and safety of adding local RT to first-line CIT in ES-SCLC.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eThis retrospective study analyzed clinical data from 132 ES-SCLC patients treated with first-line chemoimmunotherapy at our institution between January 2019 and December 2024. Patients were categorized into two groups: the chemoimmunotherapy plus radiotherapy (RT) group (n\u0026thinsp;=\u0026thinsp;73) and the chemoimmunotherapy-only (non-RT) group (n\u0026thinsp;=\u0026thinsp;59). Baseline characteristics, tumor response, and treatment-related adverse events (AEs) were compared using Chi-square. Kaplan-Meier analysis and log-rank tests were employed to assess progression-free survival (PFS), primary tumor PFS (PFS-PT), distant metastasis PFS (PFS-DM), and overall survival (OS). Cox proportional hazards models were used for univariate and multivariate analyses.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe CIT\u0026thinsp;+\u0026thinsp;RT group showed significantly better outcomes. Objective response rate (83.6% vs. 49.2%, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and disease control rate (90.4% vs. 62.7%, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) were higher with RT. Median OS (21.0 vs. 13.0 months, HR 0.514, 95% CI 0.331\u0026ndash;0.798) and PFS (9.5 vs. 6.0 months, HR 0.552, 95% CI 0.383\u0026ndash;0.796) were prolonged. RT also extended median PFS-PT (11.8 vs. 8.0 months, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and PFS-DM (11.8 vs. 7.1 months, P\u0026thinsp;=\u0026thinsp;0.010). RT was an independent protective factor for OS/PFS. consolidation RT outperformed salvage RT (both P\u0026thinsp;\u0026lt;\u0026thinsp;0.01). AE incidence (Grade I-II/III-IV) did not differ significantly.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThe addition of local radiotherapy to first-line chemo-immunotherapy significantly improves survival outcomes, including distant metastasis control, in ES-SCLC patients without significantly increasing treatment-related adverse events. Radiotherapy serves as an independent favorable prognostic factor, with consolidation timing being critical for optimal outcomes.\u003c/p\u003e","manuscriptTitle":"Radiotherapy Following Chemoimmunotherapy in Extensive- Stage Small Cell Lung Cancer: A Subgroup Analysis of Consolidation Versus Salvage Indications","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-05-07 19:22:34","doi":"10.21203/rs.3.rs-9345237/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-05-01T18:38:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"268601319769268708097837321368980492145","date":"2026-05-01T05:28:37+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-29T05:30:39+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-08T10:47:15+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-08T02:08:20+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-08T02:07:53+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Cancer","date":"2026-04-07T12:31:28+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-cancer","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bcan","sideBox":"Learn more about [BMC Cancer](http://bmccancer.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bcan/default.aspx","title":"BMC Cancer","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b696dda8-5395-4526-974a-9cc240b850e2","owner":[],"postedDate":"May 7th, 2026","published":true,"recentEditorialEvents":[{"type":"editorInvitedReview","content":"","date":"2026-05-01T18:38:36+00:00","index":45,"fulltext":""},{"type":"reviewerAgreed","content":"268601319769268708097837321368980492145","date":"2026-05-01T05:28:37+00:00","index":44,"fulltext":""},{"type":"reviewersInvited","content":"30","date":"2026-04-29T05:30:39+00:00","index":"","fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-07T19:22:34+00:00","versionOfRecord":[],"versionCreatedAt":"2026-05-07 19:22:34","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9345237","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9345237","identity":"rs-9345237","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}