Waterjet hydrodissection: First experiences and short-term outcomes of a novel approach to bladder tumor resection

Introduction: TURB is the standard approach to bladder tumors but suffers from several disadvantages. Waterjet hydrodissection is a new technology for removing superficial tumors in the GI tract promising to preserve the histological structures of biopsy specimens with favorable long-term results as recent studies have shown. The aim of this study was to show the feasibility and applicability of waterjet hydrodissection for removing papillary superficial bladder tumors. Materials and methods: In five patients diagnosed with superficial papillary bladder tumor, transurethral submucosal dissection was conducted using the T-type I-Jet HybridKnife (Erbe, Tuebingen). The resection edges were labeled by means of electrical coagulation with the HybridKnife. Subsequently, a submucosal fluid cushion specific to the tissue layer was formed by the waterjet implementation function of the HybridKnife, thereby elevating the tumorous tissue. The tumor was endoscopically extracted with a retrieval bag. Biopsy specimens of the tumor edges and base were subsequently collected. Results: All tumors could be resected en bloc, and the lamina propria was intact in all specimens, allowing the pathologist to distinguish between superficial and invasive tumors. Pathological analysis confirmed R0 resection in all samples. Conclusion: These initial results prove the feasibility of waterjet hydrodissection for removing bladder tumors. In contrast to conventional TURB, this new technique allows the pathologist to assess the entire lamina propria and the resection edges due to the en-bloc resection and to determine invasiveness as well as R0 versus R1 resection. These first results are promising, long-term oncological follow-up, and prospective randomized surveys investigating the recurrence rate have to be evaluated.