Authors' response to letter to the editor.

We thank Drs. Mandal and Goel for their interest in our work, but we disagree with their interpretation of the literature compared with our findings. While Waldert and associates did indeed find a correlation between a longer delay to nephroureterectomy (NUx) and more advanced stage, they did not report metastasis-free survival. Moreover, they found no difference in cancer-specific survival. Thus, given that we also observed a progression of local disease in some patients but found no survival differences, we hold that our results are not contradictory to the findings of Waldert and associates. In addition, we limited delayed patients to those pursuing endoscopic management vs the heterogeneous reasons for delay found in their study. We agree that elective endoscopic management is not appropriate for patients who present with muscle-invasive or high-grade disease. As we reported previously, however, endoscopic management may be considered an alternative in such patients who also have absolute indications to pursue nephron-sparing management. For patients with small lowgrade tumors, elective endoscopic management should be considered as a legitimate option if experienced personnel and the necessary equipment are available. As endoscopic technology and surgical capabilities continue to disseminate around the globe, more patients may be offered this option. We do acknowledge that endoscopic procedures are not free of complications and that there are risks associated with repeated anesthetic administrations in elderly patients. As we discussed, however, there is a substantial 90-day mortality risk associated with NUx in elderly populations, reaching 8.3% in patients > 80 years old. Given that the most common cause of death was renal insufficiency, we hold that ureteral strictures and other endoscopic complications (which in fact are uncommon) are acceptable risks for elderly patients with small low-grade upper tract urothelial carcinoma.