Abstract 316P
Background
The innovative introduction of immunotherapy has changed the landscape of SCLC treatment, however ideal markers highlighting patients who may benefit from immune checkpointinhibitors (ICIs) remains an unmet need. In this context, a new molecular model based on the expression levels of four key transcription regulators (ASCL1, NeuroD1, YAP1, POU2F3), could identify different SCLC subtypes that may be associated to variable immunogenicity and ICIs response. Moreover, clinical-biological prognostic scores have been investigated to better predict patients outcome.
Methods
We collected data of 59 SCLC patients divided in two different groups (chemotherapy=CT vs chemoimmunotherapy=CT-IO) and investigated eventual association with clinical-pathological features. Among patients treated with CT-IO, immunological ratios and scores were calculated and a wide immunohistochemical analysis was performed on 36 available tissue samples. All data were correlated with OS and PFS.
Results
Our analysis showed significative correlation between EPSILoN and OS (p=0.0006); a trend towards statistical significance was found for PFS. This score is already applied in NSCLC but, to our knowledge, its prognostic value has not been studied in SCLC yet. As regards tissue samples analysis, a low median CD31 expression (≤6 vs >6) was significantly detected in stromal intratumoral cells of both treatment groups (p=0.005). CT-IO group has been stratified by occurrence of disease progression (PD vs no-PD). Interestingly, stromal cells intra- and extratumoral YAP1 expression was higher in patients who experienced PD (9/10, 90%, p=0.04), suggesting a potential involvement of YAP1 in SCLC progression during immunotherapy.
Conclusions
For the first time, we applied dedicated clinical scores for the prognostic definition of SCLC patients: EPSILoN score may find application in clinical practice and management of these patients in the next future. Moreover,we preliminary showed that some of inflammation markers could be considered as prognostic biomarkers in SCLC and YAP-1 might serve as a negative prognostic marker linked to reduced survival rates.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.