Treatment and outcomes of limited disease small cell lung cancer (LD-SCLC) in the Canadian small cell lung cancer database (CASCADE)

BackgroundA third of SCLC patients (pts) are diagnosed with LD, which despite curative intent treatment has high relapse rates and poor overall survival (OS). Recently, the ADRIATIC trial (NCT03703297) demonstrated improved OS and progression-free survival with consolidation durvalumab following chemoradiation. We evaluated real-world treatments and outcomes of LD-SCLC in Canada to help contextualize new therapeutic options.MethodsDemographic, staging, treatment, and outcomes data were collected through CASCADE, a multi-institutional real-world evidence database of SCLC pts involving 9 academic sites across Canada. We report descriptive analyses and OS from the time of initial diagnosis.Results1314 patients were diagnosed with LD-SCLC from 2000-2022. Median age was 68 years; female, 54%; current/former smoking history, 51%/47%; ECOG 0-1, 74%; stage I, 14%; stage II, 14%; and stage III, 72%. Among all patients, 1019 (78%) received curative intent treatment: 773 (76%), concurrent chemoradiation (cCRT); 107 (11%), sequential chemoradiation (sCRT); 108 (11%), surgery; and 31 (3%), stereotactic radiation (SRS). Prophylactic cranial irradiation was used in 544/1019 (53%) of pts. Among pts receiving CRT, radiotherapy regimens included: 40 Gray/15 fractions, 32%; 45Gy/30fr twice a day (bid), 27%; 60Gy/30fr, 21%; 50Gy/25fr, 9%; other, 11%. Only 318/1019 (31%) met basic ADRIATIC trial eligibility criteria (cCRT 60-66Gy once daily or 45Gy/30 bid, 4 cycles chemotherapy, no progression after CRT). Median follow-up time was 65.2 months (mos). Median OS in all LD-SCLC patients was 20.4 mos. Among patients treated with curative intent, median OS with cCRT was 24.9 mos, sCRT 20.9 mos, surgery 37.9 mos, and SRS 20.7 mos. For ADRIATIC eligible patients, median OS was 29.6 mos. Pts receiving palliative intent therapy had poor median OS at 9.6 mos. Median OS for patients with Stage I, Stage II, and Stage III disease was 32.3 mos, 20.1 mos, and 16.8 mos, respectively.ConclusionsThere is significant variation in curative intent treatment approaches for LD-SCLC in Canada. LD-SCLC has a poor prognosis despite curative intent treatment and remains an area of high unmet need.Legal entity responsible for the studyThe authors.FundingAstraZeneca Canada Inc.DisclosureS. Moore: Financial Interests, Personal, Advisory Board: AstraZeneca, Amgen, Bristol Myers Squibb; Financial Interests, Personal, Speaker, Consultant, Advisor: AstraZeneca, Merck. R. Rittberg: Financial Interests, Personal, Speaker, Consultant, Advisor, Served on Advisory Board and received speaker honorarium.: AstraZeneca Canada Inc.; Financial Interests, Personal, Advisory Board, On Advisory Board.: Merck; Financial Interests, Personal, Speaker, Consultant, Advisor, Speaker honorarium.: Pfizer, Novartis; Financial Interests, Personal, Advisory Board: AstraZeneca. Y.J. Kim: Financial Interests, Personal and Institutional, Full or part-time Employment: AstraZeneca Canada Inc.; Financial Interests, Personal and Institutional, Stocks or ownership: AstraZeneca Canada Inc. F. Yu: Financial Interests, Personal and Institutional, Full or part-time Employment: AstraZeneca Canada Inc.; Financial Interests, Personal and Institutional, Stocks or ownership: AstraZeneca Canada Inc. S. Snow: Financial Interests, Personal, Advisory Board: Bristol Myers Squibb, Amgen, Astellas, Merck, Janssen, AstraZeneca, Taiho, BeiGene, Knight, GSK, Takeda, Lilly, Sanofi, Roche, Pfizer; Financial Interests, Institutional, Local PI: Merck, Amgen, Arcus, BMS, Sanofi, Novartis; Non-Financial Interests, Leadership Role, President of Board of Directors: Lung Cancer Canada. M.S. Kuruvilla: Financial Interests, Institutional, Advisory Board: AstraZeneca, Takeda; Financial Interests, Institutional, Writing Engagement: AstraZeneca; Financial Interests, Institutional, Other, Educational grant: AstraZeneca; Non-Financial Interests, Institutional, Product Samples: Beigene. V. Navani: Financial Interests, Personal, Advisory Board: AstraZeneca, Sanofi, Ipsen, Pfizer, Janssen, EMD Serono, Novotech; Other, Travel: Sanofi, EMD Serono. D. Dawe: Financial Interests, Personal, Advisory Board, Compensated for advisory board attendance: AstraZeneca, Merck, Pfizer, Jazz Pharmaceuticals, Roche, Novartis, Johnson & Johnson; Financial Interests, Personal, Other, Creation of educational content: Bristol Myers Squibb; Financial Interests, Institutional, Coordinating PI, Two research grants, totaling $60,000 over the last 5 years: AstraZeneca; Non-Financial Interests, Leadership Role, Chair of the CAMO Fellowship Committee: Canadian Association of Medical Oncologists; Non-Financial Interests, Project Lead, Chair of the Small Cell Lung Cancer Working Group: Canadian Cancer Trials Group. B.H. Lok: Financial Interests, Personal and Institutional, Research Grant: Pfizer, AstraZeneca; Financial Interests, Personal, Funding: AstraZeneca, Daiichi Sankyo; Non-Financial Interests, Personal, Non-financial benefits: AstraZeneca. G. Liu: Financial Interests, Personal, Advisory Board: Anheart Therapeutics Inc., Amgen, AstraZeneca, Bayer, EMD Serono, Jazz, Johnson & Johnson, Merck, Novartis, Pfizer, Roche, Sterimax, Takeda; Financial Interests, Institutional, Principal Investigator: Takeda, AstraZeneca; Financial Interests, Personal and Institutional, Research Grant: Boehringer Ingelheim, Pfizer, AstraZeneca, Takeda. C. Ho: Financial Interests, Personal, Advisory Board: Amgen, AstraZeneca, Bayer, BMS, Eisai, EMD Serono, Janssen, Merck, Novartis, Pfizer, Roche, Jazz, Sanofi; Financial Interests, Institutional, Research Grant: AstraZeneca, Roche; Non-Financial Interests, Principal Investigator: Roche, AstraZeneca. P. Wheatley-Price: Financial Interests, Personal, Advisory Board: Roche, AstraZeneca, BMS, Merck, Amgen, Lilly, Sanofi, Pfizer, Janssen; Financial Interests, Personal, Advisory Board, Advisory Board: SteriMax, GSK; Financial Interests, Institutional, Local PI: Turning Point, Jazz Pharmaceuticals, Novartis, AstraZeneca. All other authors have declared no conflicts of interest.