Efficacy Evaluation of Multi-Slice Spiral CT in Patients with Muscle-Invasive Bladder Cancer after Neoadjuvant Chemotherapy with Gemcitabine and Cisplatin.

OBJECTIVE

This study aims to evaluate the predictive utility of multi-slice spiral computed tomography (MSCT) in assessing the response to neoadjuvant chemotherapy (NAC) in patients with muscle-invasive bladder cancer (MIBC).

METHODS

The clinical data of patients with MIBC who received treatment at our institution between January 2022 and January 2024 were retrospectively analysed. The patients were assigned to an observation group or a control group according to whether pathological downstaging was achieved following NAC with a gemcitabine and cisplatin regimen. A multivariate logistic regression analysis was conducted to develop a clinical prediction model, and a receiver operating characteristic (ROC) curve was generated to assess its diagnostic performance. For the evaluation of the model's stability, all patients were randomly assigned to either a training set or a validation set in a 7:3 ratio.

RESULTS

A total of 86 patients were included in the study, among whom 46 achieved pathological downstaging with a downstaging rate of 53.49%. Multivariate logistic regression analysis identified blood flow (BF; odds ratio (OR), 95% confidence interval (CI): 0.63 (0.48-0.81)) and blood volume (BV; OR, 95% CI: 0.04 (0.00-0.46)) measured by MSCT as independent predictors of NAC efficacy (p < 0.05). In the training set, the area under the ROC curve (AUC) was 0.94 (95% CI: 0.89-0.99), with a specificity of 0.86 and a sensitivity of 0.87. In the validation set, the AUC was 0.98 (95% CI: 0.93-1.00), with a specificity of 0.84 and a sensitivity of 0.88. The Hosmer-Lemeshow goodness-of-fit test indicated good calibration, with p-values of 0.504 and 0.915 in the training and validation sets, respectively. The calibration curve demonstrated strong concordance with the ideal 45° reference line, indicating close alignment between predicted and observed probabilities. Decision curve analysis further confirmed the clinical utility of the nomogram, showing a favourable net benefit across a wide range of threshold probabilities.

CONCLUSIONS

Pre-chemotherapy BF and BV parameters measured by MSCT were identified as significant predictors of NAC efficacy in patients with MIBC. The predictive model constructed using these parameters demonstrated strong performance in forecasting pathological downstaging following NAC.