Clinical data of patients with synchronous radiotherapy for esophageal cancer in the Department of Radiology of Jiangsu Provincial People's Hospital were collected. Patients were divided into trilaciclib group (34 cases) and control group (169 cases) based on whether trilaciclib was used or not. Patients in the trilaciclib group were given trilaciclib before each chemotherapy treatment. Propensity score matching (PSM) was used to balance the baseline characteristics between the two groups on a 1:1 ratio. After pairing, the rates of bone marrow suppression and other adverse events were compared between the two groups.

chemoradiotherapy-induced myelosuppression (CIM) is the most common adverse event of concurrent chemoradiotherapy for esophageal cancer, often leading to reduction, delay or even cessation of chemotherapeutic agents. Clinical treatments for CIM mainly include various hematopoietic growth factors and blood transfusion. However, these interventions target only a single spectrum of blood cells and are susceptible to concomitant adverse events such as bone pain, thrombosis, and fever. Trilaciclib is a potent, transient, reversible CDK4/6 inhibitor and is the world's first innovative drug with lineage-wide myeloprotective effects. Its use in esophageal cancer has not been reported yet. In this study, we investigated the clinical efficacy and safety of trilaciclib in preventing myelosuppression in concurrent chemoradiotherapy for esophageal cancer for the first time.

Inclusion Criteria:

• age ≥18 years;
• pathological diagnosis of esophageal squamous cell carcinoma;
• failure to undergo surgical treatment;
• completion of definitive chemoradiotherapy or chemoradiotherapy combined with immunotherapy.

Exclusion Criteria:

• history of other malignant tumors;
• difficulty in follow-up;
• insufficient clinical information.

Patients with esophageal squamous carcinoma who received concurrent chemoradiotherapy with or without trilaciclib.