Editing Upper Urinary Tract Urothelial Cancer (section)

=====Segmental Ureterectomy=====
====== Options ======
*'''<span style="color:#ff0000">Segmental ureterectomy with ureteroureterostomy</span>'''
** '''<span style="color:#ff0000">Patients most suitable for segmental ureterectomy have small, unifocal tumors (typically 1 cm or smaller) tumors isolated to a short segment of the proximal or mid-ureter requiring resection of 2 cm or less of ureteral length to allow for primary</span>''' 
***Longer sections of ureteral involvement and resection may require more complex reconstruction techniques when kidney sparing is desired.
*'''<span style="color:#ff0000">Distal ureterectomy with ureteral reimplant</span>'''
**'''<span style="color:#ff0000">Preferred treatment for surgically eligible patients with HR and unfavorable LR cancers endoscopically confirmed as confined to the lower ureter in a functional renal unit</span>'''
***Tumor ablation considered alternative options to the gold-standard of extirpative resection
****Tumor ablation may yield less optimal results and require multiple additional procedures
**Most favorable candidates for distal ureterectomy are patients who
***Have ureteral tumors in the lower third of the ureter
***Sufficiently mobile bladder with capacity to facilitate reimplantation with or without reconfiguration of the bladder to facilitate a tension-free anastomosis (i.e., Boari flap or psoas hitch maneuver).

====== Principles ======
#'''Patient counseling''' to describe techniques, potential requirements for urinary reconstruction and associated complications including the potential impact on postoperative bladder function.
#'''Preoperative endoscopic assessment''' to evaluate sites of involvement and proximal extent of disease.
#'''Preoperative assessment of bladder capacity''' and function in cases where more extensive reconstruction such as a Boari flap are anticipated to permit a tension free ureterovesical anastomosis or the use of bowel segments.
#'''Intraoperative pathologic assessment''' (i.e., frozen sections) of proximal and distal margins to ensure complete resection with negative margins.
#Reasonable attempts to '''avoid of spillage of urine''' into the surgical field.
# '''Watertight, tension free closure''' to facilitate functional healing and avoid urine leak (of urine potentially contaminated with malignant cells).

====== Outcomes ======
* '''Reasonable alternative to RNU for well-selected patients'''
** '''<span style="color:#ff00ff">Systematic review and meta-analysis comparing segmental resection to radical nephroureterectomy (2020)</span>'''
*** Results:
**** Included 18 studies comprising 4797 patients, of which 1313 underwent segmental resection
**** High risk of bias across all domains analyzed, limiting interpretation of comparisons
**** 5-yr:
***** Recurrence-free survival: significantly worse with segmental resection
***** Cancer-specific survival: no significant difference
***** OS: no significant difference
*** Veccia, Alessandro, et al. "Segmental ureterectomy for upper tract urothelial carcinoma: a systematic review and meta-analysis of comparative studies." ''Clinical genitourinary cancer'' 18.1 (2020): e10-e20.
**'''<span style="color:#ff00ff">Systematic review and meta-analysis comparing nephron-sparing approach to radical nephroureterectomy (2016)</span>'''
*** Primary outcome: cancer-specific survival
*** Results
**** Included 22 studies published between 1999 and 2015
***** No RCTs comparing nephron-sparing approach and nephroureterectomy
**** High risk of bias across all domains analyzed, limiting interpretation of comparisons
**** Segemental ureterectomy vs. RNU (10 studies): no significant difference in cancer-specific survival
**** Endoscopic vs. RNU
***** URS vs. RNU (5 studies): no significant difference in cancer-specific survival
****** Grade-based subgroup analyses found decreased cancer-specific survival in patients undergoing URS for high-grade disease
***** Percutaneous resection vs. RNU (2 studies): conflicting findings
*** Seisen, Thomas, et al. "Oncologic outcomes of kidney-sparing surgery versus radical nephroureterectomy for upper tract urothelial carcinoma: a systematic review by the EAU non-muscle invasive bladder cancer guidelines panel." ''European urology'' 70.6 (2016): 1052-1068.
* Segmental ureterectomy of the proximal two-thirds of ureter is associated with higher failure rates than for the distal ureter.

====== Technique ======
* Risk of wound implantation by tumor is low after open segmental ureterectomy if simple precautions are followed to minimize spillage
*See [[Segmental ureterectomy|Segmental Ureterectomy]] Chapter Notes for technical aspects
*'''When performing distal ureterectomy, the entire distal ureter including the intramural ureteral tunnel and ureteral orifice should be excised, and the urinary tract should be closed in a watertight fashion.'''
**'''Bladder cuff excision'''
***Approaches
****Extravesical or transvesical (e.g., midline cystotomy)
****Open, minimally invasive or transurethral endoscopic techniques.
*****Transurethral endoscopic approaches are associated with higher recurrence rates in the bladder and may limit the ability to utilize post-NU intravesical therapies if the bladder is not fully closed
***'''The resultant hiatus in the bladder in the location of the excised ureteral orifice with or without the bladder cuff can be closed formally in a watertight fashion in one or more layers[https://pubmed.ncbi.nlm.nih.gov/37096584/]'''
****'''A formal BCE with watertight closure of the bladder cuff should be performed to'''
****#'''Avoid urinary extravasation from the bladder'''
****#'''Facilitate more rapid catheter removal'''
****#'''Permit instillation of intravesical adjuvant chemotherapy in the perioperative setting'''
****Delayed closure by secondary intension in a decompressed bladder without formal bladder closure has also been described.