Session: MP69: Bladder Cancer: Upper Tract Transitional Cell Carcinoma I
MP69-13: Holmium:YAG versus Thulium:YAG laser in endoscopic ablation of Upper Tract Urothelial Carcinoma: a comparison on perioperative outcomes and short-term follow-up
Introduction: The Holmium-YAG (Ho:YAG) laser is the most widely used laser in urology for both the treatment of stones and soft tissues. However, the Thulium-YAG (Tm:YAG) laser has become a reliable alternative for soft tissue treatment. The aim of our study is to increase evidence on the safety and efficacy of endoscopic management of upper tract urothelial carcinoma (UTUC) with the Ho:YAG and Tm:YAG lasers. Methods: 111 patients with a diagnosis of low-risk UTUC were enrolled. Exclusion criteria comprised patients with a bilateral or multifocal disease and use of antiplatelet/anticoagulant therapy. In all cases a preoperative computed tomography (CT) scan was performed with evidence of contrast-enhanced solid tissue inside the upper urinary tract. In all cases indication to ureteroscopy was given to confirm diagnosis and to perform biopsy. Endoscopic laser ablation was decided with respect to EAU guidelines recommendations: unifocal disease, tumor size < 2 cm, negative or low-grade cytology, low-grade biopsy and no invasive aspect on CT. Laser ablation was performed with Tm:YAG and Ho:YAG in 62 (Group A, 55.9%) and 49 (Group B, 44.1%) patients respectively. Three months after surgery CT scan and ureteroscopy were performed. Afterwards, CT scan was performed every 6 months. Results: Mean tumor size was 18.1 mm. Tumor was localised in the renal calyxes in 30 cases (27.0%), in the renal pelvis in 41 cases (37.0%) and inside the ureter in 40 cases (36.0%). Preoperative features were comparable between the two groups. Mean operative time was 18.2 min and 21.7 min in Groups A and B respectively (p=0.09). Mean haemoglobin drop at first postoperative day was 0.8 g/dl and 0.6 g/dl in Groups A and B (p=0.10). However, despite haemoglobin drop was not significantly different between the two treatments, a more consistent bleeding and a lower visibility were subjectively reported with the use of holmium laser. At a median follow-up of 42.3 months we observed a local recurrence in 12 patients (19.3%) in Group A and 18 (36.7%) patients in Group B (p=0.02). Conclusions: Despite perioperative outcomes were comparable between groups, a higher recurrence rate was observed after UTUC ablation with Ho:YAG laser. Lower intraoperative bleeding and better intraoperative vision were subjectively reported during surgery. These features along with a higher vaporisation effect with Tm:YAG laser may explain our results. SOURCE OF Funding: None.
