Background: Three-course neoadjuvant chemotherapy (NAC) followed by surgery has become a standard of care for locally advanced esophageal cancer (EC). However, some patients occasionally experience a poor tumor response to the third course and have a poor clinical outcome.
Methods: An exploratory analysis of data from the authors' recent multicenter randomized phase 2 trial compared patients with locally advanced EC who received two courses (n = 78) and those who received three courses (n = 68) of NAC. The association between tumor response and clinico-pathologic factors, including survival, was evaluated to identify risk factors in the three-course group.
Results: Of 68 patients who received three courses of NAC, 28 (41.2%) had a tumor reduction rate lower than 10% during the third course. This rate was associated with unfavorable overall survival (OS) and progression-free survival (PFS) compared with a tumor reduction rate of 10% or higher (2-year OS rate: 63.5% vs. 89.3%, P = 0.007; 2-year PFS rate: 52.6% vs. 79.7%, P = 0.020). The independent prognostic factors for OS were tumor reduction rate lower than 10% during the third course (hazard ratio [HR], 2.735; 95% confidence interval [CI] 1.041-7.188; P = 0.041) and age of 65 years or older (HR, 9.557, 95% CI 1.240-73.63; P = 0.030). Receiver operating characteristic curve and multivariable logistic regression analyses identified a tumor reduction rate lower than 50% after the first two courses as an independent predictor of a tumor reduction rate lower than 10% during the third course of NAC (HR, 4.315; 95% CI 1.329-14.02; P = 0.015).
Conclusion: Continuing NAC through a third course may worsen survival for patients who do not experience a response to the first two courses in locally advanced EC.
Keywords: DCF; Esophageal cancer; Multicenter randomized trial; Reduction rate; Three course; Two course.
© 2023. Society of Surgical Oncology.