Multimodal Ultrasound for Early Prognostic Assessment During Definitive Radiotherapy in Locally Advanced Cervical Cancer

ABSTRACT Purpose To investigate the prognostic value of early multimodal ultrasound parameters in patients with locally advanced cervical cancer (LACC) undergoing definitive radiotherapy. Methods This retrospective exploratory study included 31 patients with histologically confirmed cervical squamous cell carcinoma who underwent definitive radiotherapy with or without concurrent chemotherapy. Grayscale ultrasound and shear wave elastography (SWE) were performed in all patients at baseline and approximately 2 weeks after radiotherapy initiation, whereas complete contrast‐enhanced ultrasound (CEUS) data were available for 22 patients. Unfavorable outcomes were defined as progression, recurrence, or death during follow‐up after radiotherapy initiation. ROC analysis was performed to evaluate individual parameters, and a logistic regression model incorporating baseline SWE mean and tumor maximum diameter at the two‐week assessment was internally validated using 1000 bootstrap resamples to estimate optimism‐corrected performance. Exploratory time‐dependent ROC analyses were performed using progression‐free survival data to assess model discrimination at different follow‐up time points. Results Patients with unfavorable outcomes showed higher baseline SWE mean values (153 vs. 106.5 kPa, p = 0.039) and larger residual tumor maximum diameters 2 weeks after radiotherapy initiation (36 vs. 32 mm, p = 0.045). The combined model showed an apparent AUC of 0.775 and an optimism‐corrected AUC of 0.735. Exploratory time‐dependent ROC analysis yielded AUC values of 0.855, 0.840, and 0.719 at 12, 24, and 36 months, respectively. Kaplan–Meier analysis demonstrated shorter progression‐free survival in the higher‐risk group than in the lower‐risk group according to the combined model (log‐rank p = 0.022). In exploratory CEUS subgroup analysis, a greater reduction in time to peak was associated with unfavorable outcomes ( p = 0.039). Conclusions Baseline tumor stiffness and early residual tumor size assessed by multimodal ultrasound may offer complementary prognostic information for exploratory risk stratification in patients with LACC undergoing definitive radiotherapy. Further prospective validation is warranted.