Impact of baseline steroids on the efficacy of neoadjuvant immunochemotherapy in locally advanced esophageal squamous cell carcinoma.

Background: Immunochemotherapy involving the combination of programmed cell death 1/programmed cell death ligand 1 inhibitors with chemotherapy has advanced the treatment of locally advanced esophageal squamous cell carcinoma (ESCC). The use of corticosteroids as pretreatment might reduce immunotherapy efficacy.

Aim: To investigate the impact of baseline corticosteroid use on neoadjuvant immunochemotherapy (nIC) outcomes in locally advanced ESCC patients.

Methods: Patients with locally advanced ESCC who received nIC at Sun Yat-sen University Cancer Center and the Third Affiliated Hospital of Sun Yat-sen University were included. Patients were divided into dexamethasone and antihistamine groups on the basis of the administered pretreatment. Antiallergic efficacy and safety were evaluated, as well as its impact on short-term efficacy [complete pathological response (pCR), major pathological response (MPR)] and long-term efficacy [overall survival (OS), progression-free survival (PFS)] of nIC.

Results: From September 2019 to September 2023, 142 patients were analyzed. No severe treatment-related adverse events or deaths were observed. Allergy occurrence was greater in the antihistamine group (P = 0.014). Short-term efficacy was not significantly different: The pCR rates were 29.9% and 40.0%, and the MPR rates were 57.9% and 65.7% in the dexamethasone and antihistamine groups, respectively. The long-term efficacy was not significantly different: The 2 years OS rates were 95.2% and 93.5%, and the 2 years PFS rates were 90.3% and 87.8%. Subgroup analysis revealed no difference in OS between the 20 mg dexamethasone group and the < 20 mg dexamethasone group, but PFS was significantly greater in the 20 mg dexamethasone group (93.9% vs 56.4%, P = 0.001).

Conclusion: Dexamethasone or antihistamines can be used before nIC in locally advanced ESCC without affecting short- or long-term efficacy. Administering 20 mg dexamethasone before nIC may improve PFS in ESCC.