Searching for Predictive Biomarkers of Efficacy in Small Cell Lung Cancer Patients Treated With Chemotherapy-immunotherapy Combination Using Imaging Mass Cytometry (HYPE)

Small cell lung cancer patients treated with first-line atezolizumab plus platinum-etoposide regimen with available formalin fixed paraffin embedded (FFPE) biopsies at baseline will be identified from Brest University Hospital medical records and their samples will be retrieved from Brest University Hospital Pathology Laboratory for imaging mass cytometry analyses.

Clinical data will be collected for each patient, including progression-free survival (defined as the time between treatment start and date of progression according to investigator, or death from any cause) and overall survival (defined as the time between treatment start and date of death from any cause).

For imaging mass cytometry analyses, a panel of 39 metal-tagged antibodies will be used to characterize the cell composition of lung tumors at baseline (inflammatory, tumor and stromal cells).

Statistical analyses will be performed to correlate the composition of the tumor microenvironment at baseline and the survival data.

Inclusion criteria

• Patients with extensive or metastatic small cell lung cancer
• Patients who started a first line treatment with atezolizumab plus carboplatin and etoposide in routine practice before February 2021
• Patients with available tumor sample before treatment start
• No objection from living patients

Exclusion criteria

• Patients who started first line treatment with atezolizumab plus carboplatin and etoposide in routine practice after February 2021
• Patients having received immunotherapy in a clinical trial
• Patients with auto-immune disorder
• Patients under legal protection (guardianship, curatorship)
• Patients refusing to participate to the study