Renal tumor models: evaluation of ease of implementation, quality of composition, and imaging characteristics
Brian M Benway1, Jose M Cabello, Alana C Desai
1Washington University School of Medicine, Department of Surgery, Division of Urologic Surgery, Saint Louis, Missouri 63110, USA. benwayb@wustl.edu
Background And Purpose:
With the rise in detection of small renal masses that are amenable to nephron-sparing surgical approaches, there has been an increasing need for renal tumor models that create discrete lesions suitable for training exercises. We aim to investigate a handful of commonly used compounds, subjectively evaluating their ease of implementation and imaging characteristics.
Materials And Methods:
After an initial ex vivo study, we selected five compounds for an in vivo porcine investigation. These compounds included metagel with barium, Smooth-Cast 320, Silfome with and without barium, and Kromopan. The compounds were injected under laparoscopic guidance with the aim of creating discrete renal tumors. The kidneys were then imaged under ultrasonography and CT. The animals were euthanized, and nephrectomy was performed. Handling characteristics were noted.
Results:
All compounds were relatively easy to inject. Most of the compounds were susceptible to some degree of subcapsular spread. Kromopan had a high propensity for infiltration of the collecting system. On imaging, metagel was clearly distinguishable from normal renal parenchyma on both CT and ultrasonography. Silfome and Smooth-Cast were difficult to resolve on ultrasonography. Metagel was prone to rupture during surgical manipulation.
Conclusions:
No single compound provided the ideal combination of ease of implementation, resistance to extravasation, ease of resolution on imaging, and resistance to rupture. Therefore, compound selection should be dictated by the particular aims of a training simulation.
Insights
No single compound perfectly simulates renal tumors for surgical training. Researchers evaluated several materials, finding metagel best for imaging but prone to rupture, while others showed different limitations.
Area of Science:
- Urology
- Surgical Simulation
- Biomaterials
Background:
- Increasing detection of small renal masses necessitates nephron-sparing surgery.
- A need exists for effective renal tumor models for surgical training.
Purpose of the Study:
- To evaluate commonly used compounds for creating discrete renal lesions in vivo.
- To assess ease of implementation, imaging characteristics, and handling of potential renal tumor models.
Main Methods:
- Five compounds (metagel with barium, Smooth-Cast 320, Silfome +/- barium, Kromopan) were injected laparoscopically into porcine kidneys.
- Kidneys were imaged using ultrasonography and CT; handling characteristics were noted post-nephrectomy.
Main Results:
- All compounds were injectable, but most showed subcapsular spread.
- Kromopan infiltrated the collecting system; metagel was well-imaged but ruptured easily.
- Silfome and Smooth-Cast were poorly visualized on ultrasonography.
Conclusions:
- No single compound offered ideal characteristics for renal tumor simulation.
- Compound choice for training should align with specific simulation objectives.
