Radiotherapy Strategies for Use in Combined Treatment of Small-cell Lung Cancer

Inclusion Criteria

• •Histopathological confirmation of small cell lung cancer based on histological or cytological examination.
• •Primary clinical stage: Extensive stage of the disease according to VASLG classification or stage IV according to TNM classification.
• •Eastern Cooperative Oncology Group (ECOG) performance status 0-2 prior to randomization.
• •Partial response (PR) or stable disease (SD) to platinum-based doublet chemotherapy with durvalumab or atezolizumab based on restaging (positron emission tomography \[PET\]/computed tomography \[CT\] or CT or magnetic resonance imaging \[MRI\]).
• •Ability to undergo radiotherapy at a total dose of 45 Gy in 15 daily fractions of 3 Gy to the chest area and a total dose of 24 Gy administered in single fractions every 2-3 days of 8 Gy to the metastatic lesions.
• •Clinical control of brain metastases (prior whole-brain irradiation at any stage is acceptable before study entry).
• •Measurable residual disease after chemioimmunotherapy (according to RECIST 1.1 solid tumor response assessment criteria) or in case of CR/PR presence of tumor lesions not classified as measurable.
• •Volume and number (up to 10) of metastatic lesions allowing for radiotherapy in doses according to the study protocol.
• •Absence of clinically significant and uncontrolled co-morbidities with pharmacological treatment.
• •Absence of active autoimmune diseases except for diabetes, hypothyroidism, psoriasis, eczema, lichen planus, and vitiligo.
• •Adequate hematopoietic function allowing treatment with atezolizumab or durvalumab, according to the current SmPC (Summary of Product Characteristics).
• •Renal and hepatic function allowing treatment according to the current SmPC for atezolizumab or durvalumab.