To evaluate the diagnostic accuracy of CEUS for the preoperative staging of bladder cancer, which would benefit the implementation of efficient therapeutic strategies.

Bladder cancer can be grouped into non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancers (MIBC), the latter displaying high aggressiveness, a high degree of malignancy, complicated treatment, high propensity to metastasis, and poor prognosis. Currently, the clinical feasibility and accuracy of preoperative detection of muscle invasion in bladder cancer with contrast-enhanced ultrasonography (CEUS) are unclear.

To evaluate the diagnostic accuracy of CEUS for the preoperative staging of bladder cancer, which would benefit the implementation of efficient therapeutic strategies.

Inclusion Criteria:

• (a) eligible patients should be 18-year-old or older;
• (b) patients should have a histologically or cytologically confirmed diagnosis of primary bladder cancer;
• (c) patients should not have had any surgery, chemotherapy, immunotherapy, or any therapy before CEUS diagnosis.

Exclusion Criteria:

• (a) participants with confirmed to have no carcinoma of the bladder;
• (b) participants with previous pelvic surgery, who had undergone therapy, any bladder surgery, or had received chemotherapy, radiotherapy or immunotherapy;
• (c) participants diagnosed with tumor recurrence or metastasis; (d) participants who were allergic to ultrasound contrast agents or could not tolerate CEUS examination, for instance, with recent myocardial infarction, angina pectoris, cardiac insufficiency, severe cardiac arrhythmia, a right/left cardiac shunt, severe pulmonary hypertension, uncontrolled systemic hypertension, acute respiratory distress syndrome, or chronic obstructive pulmonary disease.

patients who have a histologically or cytologically confirmed diagnosis of primary bladder cancer