Inclusion Criteria:  Voluntarily participate and sign informed consent; must be at least 18 years when fisrt dose of Trilaciclib, regardless of gender: Patients with extensive small-cell lung cancer confirmed by histology or cytology Patients suitable for Trilaciclib combined with platinum/etoposide or Trilaciclib combined with topotecan treatment  Exclusion Criteria:  Patient is currently participating in other Interventional clinical studies; Patients received systemic chemotherapy other than the regimens recommended in inclusion criteria 4 During Trilaciclib treatment.