Trop2-Targeted NIR-II Fluorescent Probe for Identifying Bladder Cancer in Ex Vivo Bladder Samples

> Bladder cancer is one of the most common human malignancies. Approximately 70% of newly diagnosed patients present with non-muscle-invasive bladder cancer (NMIBC). White-light endoscopy, the routine clinical method, misses up to 30% of lesions especially small satellite tumors and flat carcinoma in situ (CIS), contributing to high recurrence up to 70%. Existing alternative endoscopic imaging techniques suffer from high false-positive rates or narrow field-of-view. Trop2 is overexpressed in urothelial bladder carcinoma, and Trop2-targeted antibody-drug conjugate has been FDA-approved for urothelial carcinoma, validating Trop2 as a reliable tumor biomarker.

This phase 2, single-center, single-arm prospective study plans to enroll 30 suspected or confirmed bladder tumor patients scheduled for radical cystectomy. After surgical removal of whole-bladder specimen ex vivo, 50 mL TTP-ICG solution (20 μg/mL) is instilled into the lumen of isolated bladder for 3-minute incubation. After discarding probe solution, the bladder lumen is rinsed 3 times with normal saline. Near-infrared-II fluorescence imaging is performed over the entire inner bladder surface. Lesions highlighted by fluorescence are sampled for histopathological examination. With postoperative histopathology as gold standard, we calculate sensitivity, specificity, false-positive rate, false-negative rate of this imaging system for detecting malignant lesions. Fluorescence intensity of tumor foci and normal bladder mucosa are measured to explore correlation between fluorescence signal and pathological diagnosis. This ex-vivo study provides pre-clinical evidence for future in-vivo application, aiming to reduce missed diagnosis and recurrence of NMIBC.

• TTP-ICG fluorescent probe (Drug): After radical cystectomy, 50 mL TTP-ICG solution (20 μg/mL) is instilled into lumen of isolated bladder specimen for 3 minutes incubation. Then probe solution is drained; bladder lumen washed 3 times by normal saline(30 seconds per time). Near-infrared-II fluorescence imaging is performed on inner bladder surface. Fluorescent highlighted lesions are harvested for pathological examination.

Primary outcomes

• Diagnostic Sensitivity of ex-vivo Trop2-targeted NIR-II fluorescence imaging for detecting malignant bladder lesions [Within 7 days after collection of ex-vivo bladder specimen, after histopathology report available]: Sensitivity of TTP-ICG rapid-incubation NIR-II fluorescence imaging to identify malignant bladder lesions in ex-vivo radical-cystectomy specimens. Histopathology serves as gold-standard reference. Sensitivity = true-positive / (true-positive + false-negative).
• Diagnostic Specificity of ex-vivo Trop2-targeted NIR-II fluorescence imaging for detecting malignant bladder lesions [Within 7 days after collection of ex-vivo bladder specimen, after histopathology report available]: Specificity of TTP-ICG rapid-incubation NIR-II fluorescence imaging to identify malignant bladder lesions in ex-vivo radical-cystectomy specimens. Histopathology serves as gold-standard reference. Specificity = true-negative / (true-negative + false-positive)
• False-Positive Rate of ex-vivo Trop2-targeted NIR-II fluorescence imaging for detecting malignant bladder lesions [Within 7 days after collection of ex-vivo bladder specimen, after histopathology report available]: False-positive rate of TTP-ICG rapid-incubation NIR-II fluorescence imaging for bladder-cancer lesion detection on ex-vivo specimens, using histopathology as gold standard. False-positive rate = false-positive / (true-negative + false-positive)
• False-Negative Rate of ex-vivo Trop2-targeted NIR-II fluorescence imaging for detecting malignant bladder lesions [Within 7 days after collection of ex-vivo bladder specimen, after histopathology report available]: False-negative rate of TTP-ICG rapid-incubation NIR-II fluorescence imaging for bladder-cancer lesion detection on ex-vivo specimens, using histopathology as gold standard. False-negative rate = false-negative / (true-positive + false-negative)

Secondary outcomes

• Near-infrared-II fluorescence intensity of tumor lesions and normal bladder mucosa [Within 7 days after collection of ex-vivo bladder specimen, after histopathology report available]: Quantitative NIR-II fluorescence intensity values measured for malignant tumor lesions and normal bladder mucosal epithelium on ex-vivo bladder specimens

Sex: All, ages: 18 Years to 80 Years

Inclusion Criteria:

1. Suspected or confirmed bladder tumor patients who are scheduled to undergo radical cystectomy.
2. Able to provide written informed consent and comply with study protocol.

Exclusion Criteria:

1. Suffering from other invasive malignant tumors.
2. With severe comorbidities including congenital malformation, acute active inflammation, cachexia, myocardial infarction or stroke within past 6 months, severe hepatic or renal insufficiency.
3. Pregnant or lactating female subjects.
4. Participated in another clinical trial within past 30 days.