We would like to thank Bjurlin et al for their comments on our recently published study. As already discussed in the article, the aim of our study was to report outcomes and describe current techniques in the management of “simple” benign ureteral strictures using robotic-assisted surgery [1]. As a consequence, patients requiring complex reconstructive procedures, such as those required for either multifocal or extended ureteral strictures, were excluded. Unfortunately, some key information such as ureteral stricture length was not available for all patients, and these data were not reported in the paper. When looking at individuals for whom this information was available, the mean ureteral stricture length was 12 mm (range 5–40 mm). The authors should indeed be congratulated for their pioneering experience with robot-assisted ureteral reconstruction using oral mucosa grafts [2]. Their preliminary experience with four patients with ureteral strictures of up to 6 cm showed promising functional results. The idea was driven by previous experience in urethral reconstruction in which the oral mucosa graft is sutured to the corpora cavernosa and the urethra, which is opened along its dorsal surface and sutured to the lateral margins of the graft. Although regeneration of ureteral mucosa might be facilitated by the graft, which acts as an epithelial roof strip, the main risk remains the formation of scar tissue due to poor vascularization. As suggested by the authors, this approach may however overcome the traditional metabolic problems related to ileal conduit interposition. However, as for every surgical innovation, validation studies including more patients and with longer follow-up time are required before this approach could be recommended in clinical practice. Current European Association of Urology guidelines on ureteral injury repair suggest the use of either ureterocalicostomy or transureterostomy-ureterostomy for proximal and mid-ureteral extensive injury, while a complete ileal interposition graft or renal autotransplantation can be considered in the case of complete ureteral injury [3]. Several others experimental techniques for ureteral substitution have also been reported. For example, Brandao et al [4] reported their experience with robot-assisted ureteral reconstruction using a tubularized peritoneal flap in an animal model. Xu et al [5] developed a tissue-specific scaffold that could serve as a substrate for the growth of urothelial cells and maintenance of their differentiated phenotype. While the results of these studies are promising, further research is needed to demonstrate their applicability to humans. Finally, we decided to focus only on the treatment of benign ureteral strictures, as there is no consensus to date regarding the use of robotic-assisted surgery for segmental ureterectomy given the lack of studies comparing oncologic outcomes between the open and robotic approaches, as well as the hypothetical risk of spillage/seeding of tumor cells. Conflicts of interest The authors have nothing to disclose. References [1] Buffi NM, Lughezzani G, Hurle R, et al. Robot-assisted surgery for benign ureteral strictures: experience and outcomes from four tertiary care institutions. Eur Urol. In press. http://dx.doi.org/10.1016/j.eururo.2016.07.022 [2] L.C. Zhao, Y. Yamaguchi, D.J. Bryk, S.A. Adelstein, M.D. Stifelman Robot-assisted ureteral reconstruction using buccal mucosa Urology, 86 (2015), pp. 634–638 Article | PDF (362 K) | View Record in Scopus | Citing articles (2) [3] E. Serafetinides, N.D. Kitrey, N. Djakovic, et al. Review of the current management of upper urinary tract injuries by the EAU Trauma Guidelines Panel Eur Urol, 67 (2015), pp. 930–936 Article | PDF (710 K) | View Record in Scopus | Citing articles (3) [4] Brandao LF, Laydner H, Akca O, et al. Robot-assisted ureteral reconstruction using a tubularized peritoneal flap: a novel technique in a chronic porcine model. World J Urol. In press. http://dx.doi.org/10.1007/s00345-016-1840-4 [5] Y. Xu, W. Fu, Z. Wang, G. Li, X. Zhang A tissue-specific scaffold for tissue engineering-based ureteral reconstruction PLoS One, 10 (2015), p. e0120244
Reply to Marc A. Bjurlin, Lee C. Zhao, and Michael D. Stifelman's Letter to the Editor Re: Nicolò Maria Buffi, Giovanni Lughezzani, Rodolfo Hurle, et al. Robot-assisted Surgery for Benign Ureteral Strictures: Experience and Outcomes from Four Tertiary Care Institutions.
Buffi N;Lughezzani G;Guazzoni G;
2016-01-01
Abstract
We would like to thank Bjurlin et al for their comments on our recently published study. As already discussed in the article, the aim of our study was to report outcomes and describe current techniques in the management of “simple” benign ureteral strictures using robotic-assisted surgery [1]. As a consequence, patients requiring complex reconstructive procedures, such as those required for either multifocal or extended ureteral strictures, were excluded. Unfortunately, some key information such as ureteral stricture length was not available for all patients, and these data were not reported in the paper. When looking at individuals for whom this information was available, the mean ureteral stricture length was 12 mm (range 5–40 mm). The authors should indeed be congratulated for their pioneering experience with robot-assisted ureteral reconstruction using oral mucosa grafts [2]. Their preliminary experience with four patients with ureteral strictures of up to 6 cm showed promising functional results. The idea was driven by previous experience in urethral reconstruction in which the oral mucosa graft is sutured to the corpora cavernosa and the urethra, which is opened along its dorsal surface and sutured to the lateral margins of the graft. Although regeneration of ureteral mucosa might be facilitated by the graft, which acts as an epithelial roof strip, the main risk remains the formation of scar tissue due to poor vascularization. As suggested by the authors, this approach may however overcome the traditional metabolic problems related to ileal conduit interposition. However, as for every surgical innovation, validation studies including more patients and with longer follow-up time are required before this approach could be recommended in clinical practice. Current European Association of Urology guidelines on ureteral injury repair suggest the use of either ureterocalicostomy or transureterostomy-ureterostomy for proximal and mid-ureteral extensive injury, while a complete ileal interposition graft or renal autotransplantation can be considered in the case of complete ureteral injury [3]. Several others experimental techniques for ureteral substitution have also been reported. For example, Brandao et al [4] reported their experience with robot-assisted ureteral reconstruction using a tubularized peritoneal flap in an animal model. Xu et al [5] developed a tissue-specific scaffold that could serve as a substrate for the growth of urothelial cells and maintenance of their differentiated phenotype. While the results of these studies are promising, further research is needed to demonstrate their applicability to humans. Finally, we decided to focus only on the treatment of benign ureteral strictures, as there is no consensus to date regarding the use of robotic-assisted surgery for segmental ureterectomy given the lack of studies comparing oncologic outcomes between the open and robotic approaches, as well as the hypothetical risk of spillage/seeding of tumor cells. Conflicts of interest The authors have nothing to disclose. References [1] Buffi NM, Lughezzani G, Hurle R, et al. Robot-assisted surgery for benign ureteral strictures: experience and outcomes from four tertiary care institutions. Eur Urol. In press. http://dx.doi.org/10.1016/j.eururo.2016.07.022 [2] L.C. Zhao, Y. Yamaguchi, D.J. Bryk, S.A. Adelstein, M.D. Stifelman Robot-assisted ureteral reconstruction using buccal mucosa Urology, 86 (2015), pp. 634–638 Article | PDF (362 K) | View Record in Scopus | Citing articles (2) [3] E. Serafetinides, N.D. Kitrey, N. Djakovic, et al. Review of the current management of upper urinary tract injuries by the EAU Trauma Guidelines Panel Eur Urol, 67 (2015), pp. 930–936 Article | PDF (710 K) | View Record in Scopus | Citing articles (3) [4] Brandao LF, Laydner H, Akca O, et al. Robot-assisted ureteral reconstruction using a tubularized peritoneal flap: a novel technique in a chronic porcine model. World J Urol. In press. http://dx.doi.org/10.1007/s00345-016-1840-4 [5] Y. Xu, W. Fu, Z. Wang, G. Li, X. Zhang A tissue-specific scaffold for tissue engineering-based ureteral reconstruction PLoS One, 10 (2015), p. e0120244I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
