Abstract 1658P
Background
Most of SCLC p are diagnosed with ED stage with a median overall survival (mOS) around 10 months (mo). However, nearly 3-5% of them show a survival > 24 mo. The aim of this study was to identify clinical factors related to LTS with ED-SCLC.
Methods
We retrospectively included 161 p with ED-SCLC, treated between 2010-2018 at our institution. Clinical and pathological data were obtained from the electronic medical records. LTS was defined as survival ≥ 24 mo from the diagnosis. We compared categorical data between LTS and non-LTS-SCLC p using the Chi-square test. A survival analysis using the Kaplan-Meier method compared median progression free survival (mPFS) and mOS by log-rank test.
Results
Median age was 65y, 81% were male and 96% former or current smokers. 90% had stage IV at diagnosis. Most common metastatic sites were liver (37%), bone (33%), adrenal (19%), lung (17%), and brain (13%). 61% had a PS 0-1 and 6% had a paraneoplastic syndrome. 89% of the p received first-line chemotherapy (52% cisplatin-based). Sixty-three p developed some grade 3-4 toxicity. 22% received prophylactic intracranial irradiation and 11% thoracic radiotherapy. Overall response rate (ORR) was 63%, with 7 complete responses and 95 partial responses. mOS and mPFS for the entire cohort was 8.5 and 8.3 mo, respectively. 23(16%) p fit the definition for LTS. mOS was 35 months (95% CI 28.4-41.5 vs 7.4 mo (95% CI 6.3-8.5) (p=0.002) in the LTS and non-LTS cohorts, respectively. mPFS was 19.5 (95% CI 15.9-23.1) mo vs 7.3 (95% CI 6.3-8.3) mo (p=0.002) in the LTS and non-LTS cohorts, respectively. A time to progression from the end of first-line treatment >6 mo (p=0.02), rechallenge with platinum chemotherapy (p= 0.002) and immunohistochemical (IHC) positivity in tumor sample of Cam52 (p=0.015), synaptophysin (p=0.005) and CD56 (p=0.015) have showed a significant association with LTS. Other clinical factors such as PS, brain and liver metastases, type of platinum, paraneoplastic syndrome, LDH levels, neutrophils/lymphocytes ratio did not differ between groups.
Conclusions
We found interesting clinical associations with LTS phenotype. Nevertheless, molecular understanding will be crucial to elucidate the nature of LTS clinical difference behaviour.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
T. Moran: Financial Interests, Personal, Advisory Board: Boehringer Ingelheim; Financial Interests, Personal, Advisory Board: Roche; Financial Interests, Personal, Advisory Board: AstraZeneca; Financial Interests, Personal, Advisory Board: BMS. E. Carcereny: Financial Interests, Personal, Speaker’s Bureau: AstraZeneca; Financial Interests, Personal, Speaker’s Bureau: Boehringer Ingelheim; Financial Interests, Personal, Speaker’s Bureau: Bristol Myers Squib; Financial Interests, Personal, Speaker’s Bureau: MSD; Financial Interests, Personal, Speaker’s Bureau: Novartis; Financial Interests, Personal, Speaker’s Bureau: Roche; Financial Interests, Personal, Speaker’s Bureau: Takeda; Financial Interests, Personal, Speaker’s Bureau: Pfizer; Financial Interests, Personal, Advisory Board: AstraZeneca; Financial Interests, Personal, Advisory Board: Boehringer Ingelheim; Financial Interests, Personal, Advisory Board: Bristol Myers Squib; Financial Interests, Personal, Advisory Board: MSD; Financial Interests, Personal, Advisory Board: Novartis; Financial Interests, Personal, Advisory Board: Roche; Financial Interests, Personal, Advisory Board: Takeda. A. Hernández: Financial Interests, Personal, Invited Speaker: Bristol Myers Squibb; Financial Interests, Personal, Invited Speaker: Roche; Financial Interests, Personal, Advisory Board: Boehringer Ingelheim. M. Saigi: Financial Interests, Personal, Other: BMS; Financial Interests, Personal, Other: Pfizer. A. Estival Gonzalez: Financial Interests, Personal, Invited Speaker: Roche; Financial Interests, Personal, Invited Speaker: MSD; Financial Interests, Personal, Invited Speaker: AstraZeneca; Financial Interests, Personal, Invited Speaker: PharmaMar. M. Domenech Vinolas: Financial Interests, Personal, Invited Speaker: Bristol Meyers Squibb; Financial Interests, Personal, Invited Speaker: Roche; Financial Interests, Personal, Invited Speaker: AstraZeneca. All other authors have declared no conflicts of interest.