Prognostic value of pathological response to neoadjuvant chemotherapy in bulky stage Ib2 and IIa cervical squamous cell cancer patients

Neoadjuvant chemotherapy (NAC) is widely used to treat patients with locally advanced cervical cancer. Optimal pathological response to neoadjuvant therapy has proven to be a good prognostic indicator for patient survival, but the prognostic significance of a partial response remains unclear. The aim of this study was to identify prognostic predictors for patients with partial response. We included in the study 190 patients with bulky stage Ib2 or IIa cervical squamous cell cancer, who underwent neoadjuvant chemotherapy followed by surgery. A novel pathological grading system, including optimal response (complete disappearance of tumor, grade 1), viable tumor cells occupying <²/₃ (grade 2) or >²/₃ (grade 3) of the tumor bed area and extra-cervical tumor deposits (grade 4), was developed and associations with disease-free survival and overall survival were studied. Survival analysis was conducted using log-rank testing and Cox regression analysis. We found statistically significant differences between 4 different pathological response groups both in terms of disease-free survival (p = 0.001) and overall survival (p = 0.003). Combining adjacent survival curves in the pathological grading system allowed us to identify response grade 2 patients with disease-free and overall survival similar to those of optimal response patients (p = 0.000, p = 0.002). Multivariate analyses showed that the pathological response grading system is the only independent predictor for progression-free survival and overall survival (p = 0.001 and p = 0.007). A response grading system based on pathological parameters may be useful to predict both progression-free and overall survival in bulky stage Ib2 and IIa cervical squamous cell cancer patients treated with NAC.