Impact of relative dose intensity of docetaxel, cisplatin, and 5-fluorouracil neoadjuvant chemotherapy on survival of esophageal squamous cell cancer patients.

INTRODUCTION: This study aimed to clarify the impact of the average relative dose intensity (RDI) of neoadjuvant chemotherapy with docetaxel, cisplatin, and 5-fluorouracil (DCF-NAC) for resectable locally advanced esophageal squamous cell carcinoma (ESCC).

MATERIALS AND METHODS: To identify the optimal RDI, recurrence-free survival (RFS) and cumulative incidence function for recurrence (CIF) were calculated in low and high RDI groups with any cut-off points. The optimal RDI was defined as the highest RDI administered with a significant increase in either RFS or CIF. The clinicopathological characteristics of the two groups divided by optimal RDI were investigated. The preoperative prognostic factors associated with RFS were confirmed by multivariable Cox proportional hazards model.

RESULTS: Among the 150 eligible patients treated with DCF-NAC from 2010 to 2020, 3-year RFS and CIF were 56.3% and 37.8% in 90 patients in the less than 80% RDI group (<80% RDI), and 73.3% and 26.7% in 60 patients in the more than or equal to 80% RDI group (≥80% RDI), respectively. The optimal cut-off RDI was identified as 80%. The <80% RDI group included older individuals, a lower value of creatinine clearance, a higher Charlson Comorbidity Index, reduced RDI at first course, and grade 1-0 in the histopathological tumor response than the ≥80% RDI group. R0 resection and postoperative complication rates were equal in both groups. Cox proportional hazards model identified the response rate and RDI as predictors of recurrence free survival.

CONCLUSION: An average RDI of more than or equal to 80% improved prognosis in patients receiving DCF-NAC for ESCC.