Upper Tract Urothelial Carcinoma
Conditions
Keywords
UTUC, intravascular ultrasound, IVUS, intraluminal ultrasound; ureter, renal pelvis, invasion depth, T stage, radical nephroureterectomy
Brief summary
Upper tract urothelial carcinoma (UTUC) is difficult to stage accurately because cross-sectional imaging and ureteroscopic biopsy may not reliably demonstrate muscular or periureteral invasion. This exploratory study evaluates whether a 60-MHz OptiCross HD intravascular ultrasound (IVUS) catheter can be safely introduced into the renal pelvis or ureter during planned surgery and provide intraluminal images that correspond to the final pathologic T stage. Fifteen adults with suspected or confirmed UTUC who are already scheduled for radical nephroureterectomy (RNU) will undergo one IVUS examination immediately before surgery. The IVUS result will not alter the planned treatment. Three independent reviewers who are blinded to clinical and pathologic information will assess invasion depth and image quality. IVUS-based T stage will be compared with postoperative pathology. Technical success, visualization of ureteral wall layers and lesion boundaries, and adverse events will also be evaluated through 3 months after surgery.
Detailed description
This is a prospective, single-center, single-arm, investigator-initiated exploratory device study conducted at Severance Hospital. Eligible participants are adults with UTUC diagnosed or strongly suspected on imaging and/or ureteroscopic biopsy for whom RNU has already been selected as the standard treatment. Participation does not change the planned operation. After written informed consent and confirmation of eligibility, the OptiCross HD 60-MHz IVUS catheter is advanced over a 0.014-inch guidewire to the renal pelvis or ureteral lesion under endoscopic and fluoroscopic guidance during general anesthesia. A short manual or automated pullback is performed to acquire cross-sectional images of the lesion and adjacent upper urinary tract wall. The catheter is removed immediately after imaging, and the planned RNU is then performed. IVUS images are reviewed independently by three specialists who did not participate in the procedure and are blinded to preoperative clinical information and final pathology. Each reviewer assigns an IVUS-based T stage and records whether the urothelium, muscularis, and adventitia can be distinguished, whether the lesion boundary is visualized, and whether image quality is diagnostically adequate. A majority interpretation from at least two of the three reviewers is used for the main concordance analysis. The primary analysis compares IVUS-based T stage with the final pathologic pT stage from the resected specimen. Secondary analyses include technical success, visualization of the three wall layers, lesion-boundary clarity, inter-reviewer agreement, and device- or procedure-related adverse events. Safety is assessed during the procedure, during hospitalization, at approximately 4 weeks, and at the final follow-up approximately 3 months after surgery.
Interventions
DEVICEOptiCross HD Coronary Imaging Catheter
A 60-MHz OptiCross HD IVUS catheter is advanced over a 0.014-inch guidewire to the upper urinary tract lesion during the planned operative procedure. Cross-sectional images are acquired by manual or automated pullback over the lesion, after which the catheter is removed and the planned radical nephroureterectomy proceeds. The IVUS result is not used to alter treatment.
Sponsors
Yonsei University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Intervention model description
All enrolled participants receive the same IVUS imaging procedure immediately before the planned radical nephroureterectomy.
Eligibility
Sex/Gender
ALL
Age
19 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Adults aged 19 years or older, male or female. 2. UTUC diagnosed or strongly suspected based on preoperative CT or MRI and ureteroscopic biopsy. 3. A lesion identified on imaging for which the depth of invasion is difficult to determine and surgery is considered necessary. 4. RNU has been definitively selected by the treating physician, allowing direct comparison of IVUS findings with postoperative pathology. 5. Upper urinary tract anatomy permits safe passage of the 3.1-F IVUS catheter to the lesion. 6. Ability and willingness to provide written informed consent.
Exclusion criteria
1. Ureteral stricture, severe angulation, congenital anomaly, or other anatomy that prevents safe catheter advancement. 2. Definite distant metastasis (M1) or adjacent-organ invasion (T4) on imaging. 3. Active urinary tract infection or uncontrolled coagulopathy that increases the risk of ureteroscopic manipulation. 4. Pregnancy or breastfeeding. 5. Any systemic condition or other circumstance judged by the investigator to make participation inappropriate or to interfere with interpretation of the study results.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Concordance Between IVUS-Based T Stage and Final Pathologic T Stage | At final pathology review, within 4 weeks after radical nephroureterectomy | The IVUS-based T stage (Ta, T1, T2, or T3 or higher) assigned by each blinded reviewer and the majority interpretation from at least 2 of 3 reviewers will be compared with the final surgical pathology pT stage. Concordance rate will be calculated as the number of evaluable participants with matching IVUS and pathology stages divided by the total number of evaluable participants, multiplied by 100. Agreement will also be explored using kappa statistics. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Visualization of the Three Upper Urinary Tract Wall Layers | During blinded image review, within 4 weeks after surgery | Proportion of evaluable examinations in which the urothelium, muscularis, and adventitia are distinguishable. |
| Clarity of Lesion-Boundary Visualization | During blinded image review, within 4 weeks after surgery | Lesion boundary is rated as clear, partially clear, or unclear by each blinded reviewer. |
| Technical Success of IVUS Catheter Placement and Image Acquisition | During the intraoperative IVUS procedure | Proportion of attempted procedures in which the catheter reaches the target lesion and diagnostically interpretable images are acquired. |
| Incidence of IVUS-Related Adverse Events | From IVUS catheter insertion through the final follow-up, up to 3 months after surgery | Number and proportion of participants with device- or procedure-related adverse events, including hematuria, pain, mucosal injury, perforation, catheter malfunction, or other complications, summarized by severity and relatedness. |
Contacts
CONTACTWon Sik Ham, Professor
CONTACTJee Soo Park, Study Contact
Outcome results
None listed