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Updated: Jun 26, 2026
An Orthotopic Bladder Tumor Model and the Evaluation of Intravesical saRNA Treatment
Published on: July 28, 2012
Preventing bladder tumor implantation with photodynamic therapy in a rat model mimicking post-fluorescence guided
Saoussen Berrahmoune1, Lina Bezdetnaya, Agnès Leroux
1Centre de Recherche en Automatique de Nancy, Nancy University, CNRS and Centre Alexis Vautrin, Vandoeuvre lès Nancy, France.
Purpose:
Fluorescence guided transurethral resection has gained acknowledgment from the urological community and it is progressively becoming more applied. It has been shown to decrease the recurrence rate of nonmuscle invasive bladder cancer due to incomplete resection due to lack of visualization. The implantation of viable tumor cells seeded during transurethral resection is another reason for recurrence. We investigated whether applying photodynamic therapy on sensitized tumor cells would decrease the amount of viable intraluminal cells and tumor cell implantation.
Material And Methods:
Two models were designed to mimic the situation after fluorescence guided transurethral resection, including partly or fully de-epithelialized bladders and circulating tumor cells loaded with protoporphyrin IX. Photodynamic therapy was performed. Controls consisted of no drug with no light, light only and drug only. Immediately after photodynamic therapy the intravesical contents were retrieved and clonogenic assays were performed on cells. Bladders were harvested 10 days after cell administration and subjected to pathological analysis.
Results:
In the photodynamic therapy and control groups tumor volume was proportional to the instilled cell load. Clonogenic assays showed that viable cells were decreased a tenth of the initial administered amount. Tumor implantation decreased to less than a fifth of control values.
Conclusions:
Photodynamic therapy can effectively decrease the amount of viable tumor cells in the bladder lumen. This results in a significant decrease in tumor implantation. This technique could possibly be used to further decrease the recurrence rate of nonmuscle invasive bladder cancer.
Insights
Photodynamic therapy significantly reduces viable tumor cells after bladder cancer surgery, decreasing tumor implantation and potentially lowering recurrence rates for nonmuscle invasive bladder cancer.
Area of Science:
- Urology
- Oncology
- Photodynamic Therapy
Background:
- Fluorescence-guided transurethral resection is increasingly used for nonmuscle invasive bladder cancer (NMIBC).
- Recurrence in NMIBC is linked to incomplete resection and tumor cell implantation during surgery.
- Current methods struggle to eliminate all viable tumor cells post-resection.
Purpose of the Study:
- To investigate if photodynamic therapy (PDT) can reduce viable tumor cells in the bladder lumen after simulated transurethral resection.
- To assess PDT's efficacy in decreasing intraluminal tumor cell load and subsequent tumor implantation.
- To explore PDT as an adjunct therapy for NMIBC recurrence prevention.
Main Methods:
- Two models simulating post-resection conditions were used, including de-epithelialized bladders and tumor cells sensitized with protoporphyrin IX.
- Photodynamic therapy was applied, with controls including no drug/light, light only, and drug only.
- Clonogenic assays assessed viable cells, and bladders were analyzed for tumor implantation 10 days post-procedure.
Main Results:
- Photodynamic therapy significantly reduced viable tumor cells to one-tenth of the initial amount.
- Tumor implantation was reduced to less than one-fifth of control values.
- Tumor volume correlated with the initial cell load in both PDT and control groups.
Conclusions:
- Photodynamic therapy effectively eliminates viable tumor cells within the bladder lumen.
- This reduction in viable cells leads to a significant decrease in tumor implantation.
- PDT shows promise as a method to further reduce NMIBC recurrence rates.
