Segmental Ureterectomy

Segmental ureterectomy is a kidney-sparing extirpative option for selected upper tract urothelial carcinoma, removing the diseased ureteral segment with reconstruction of urinary continuity. It is a reasonable alternative to radical nephroureterectomy in well-selected patients.

Indications and Candidate Selection

• Segmental ureterectomy with ureteroureterostomy — best for small, unifocal tumours (typically ≤1 cm) isolated to a short proximal or mid-ureteral segment requiring resection of ≤2 cm to allow a primary anastomosis. Longer resections need more complex reconstruction.
• Distal ureterectomy with ureteral reimplant — the preferred treatment for surgically eligible patients with high-risk or unfavorable low-risk cancers endoscopically confirmed as confined to the lower ureter in a functional renal unit. Most favorable candidates have lower-third ureteral tumours and a sufficiently mobile, capacious bladder for a tension-free anastomosis (with or without a Boari flap or psoas hitch).
• Segmental resection of the proximal two-thirds of the ureter has higher failure rates than distal resection.

Principles

• Counsel the patient on technique, possible reconstruction, complications, and the potential impact on bladder function.
• Preoperative endoscopic assessment to define involved sites and the proximal extent of disease.
• Preoperative assessment of bladder capacity/function when more extensive reconstruction (e.g. Boari flap) is anticipated.
• Intraoperative frozen-section analysis of proximal and distal margins to confirm negative margins.
• Avoid spillage of (potentially malignant) urine into the field; use a watertight, tension-free closure. (The risk of wound implantation after open segmental ureterectomy is low if spillage is minimized.)

Outcomes

A reasonable alternative to RNU in well-selected patients:

• Veccia 2020 (meta-analysis, 18 studies, 4,797 patients; 1,313 segmental resections) — 5-year recurrence-free survival was significantly worse with segmental resection, but cancer-specific and overall survival did not differ.
• Seisen 2016 (EAU systematic review) — segmental ureterectomy vs RNU showed no significant difference in cancer-specific survival; high risk of bias across studies.

Technique — Proximal or Mid-Ureter

Achieving a clear margin while mobilizing enough well-vascularized ureter for a tension-free anastomosis is the major challenge. Open approach (full or modified flank position; flank incision from the tip of the 12th rib):

1. Via an extraperitoneal approach, identify and mobilize the ureter and secure it with vessel loops.
2. Palpate the tumour and ligate the ureter 1–2 cm above and below the suspected margin (confirmable on preoperative cross-sectional imaging).
3. Excise the diseased segment and confirm clear margins by frozen section.
4. After regional lymphadenectomy, spatulate both ends and anastomose with interrupted 4-0 Vicryl over a ureteral stent. For longer defects, mobilize and perform a renal descensus to add proximal length.

Technique — Distal Ureter

Reconstruction is by ureteroneocystostomy, escalating as needed for length. When performing distal ureterectomy, excise the entire distal ureter including the intramural tunnel and orifice, and close the urinary tract watertight.

Bladder cuff excision — extravesical or transvesical (e.g. midline cystotomy), open or minimally invasive. Transurethral endoscopic cuff techniques are associated with higher bladder recurrence and may preclude post-operative intravesical therapy if the bladder is not fully closed; a formal bladder cuff excision with watertight closure is preferred (avoids extravasation, permits faster catheter removal and perioperative intravesical chemotherapy).

• Simple ureteroneocystostomy — extravesical (incise detrusor to mucosa, anastomose full-thickness ureter to bladder mucosa with 3-0 Vicryl, then close detrusor over the ureter for a non-refluxing tunnel) or intravesical (anterior cystotomy, 2–3 cm submucosal tunnel). Whether to make the anastomosis refluxing or non-refluxing is debated — non-refluxing limits infection to the lower tract and may avoid upper-tract seeding, while refluxing eases upper-tract surveillance.
• Psoas hitch — gains ~5 cm of length. Mobilize the bladder anteriorly/laterally (divide the round ligament in women; the contralateral superior vesical artery may be divided for more mobility), complete the ureterovesical anastomosis, and suture the ipsilateral bladder dome to the psoas tendon. Avoid genitofemoral nerve injury — though the femoral nerve is more commonly injured than the genitofemoral during a psoas hitch.
• Boari flap — gains another 10–15 cm and can sometimes reach the renal pelvis. Obtain a preoperative cystogram for bladder capacity (a small, irradiated bladder is a contraindication). Develop a U-shaped (or L-shaped for more length) bladder-wall flap with the base ≥2 cm wider than the apex for blood supply and a flap width ≥3× the ureteral diameter; secure the tip to the psoas, anastomose the spatulated ureter end-to-end, then tubularize and close in two layers over a ureteral catheter.

After any of these, leave a retroperitoneal suction drain and a Foley for 7–10 days; obtain a cystogram before Foley removal after extensive reconstruction.

Technique — Ileal Ureter Replacement

For a long diseased ureteral segment, an ileal segment can reconstruct the urinary tract (the appendix has also been used). Through a midline intraperitoneal incision, harvest 20–25 cm of ileum at least 15 cm from the ileocecal valve and re-establish bowel continuity (stapled anastomosis). Anastomose the ileal segment to the renal pelvis proximally (end-to-end, isoperistaltic; end-to-side if the proximal ureter is healthy) and to the posterior bladder wall distally (end-to-side, intravesical, two layers). Leave a retroperitoneal suction drain and a large Foley for ≥1 week (irrigate as needed); a nephrostomy tube may be used. Obtain a cystogram and nephrostogram before removing tubes.

Key Exam Points

• Segmental/distal ureterectomy is a kidney-sparing option for UTUC: small unifocal proximal/mid tumours (≤1 cm, ≤2 cm resection) for ureteroureterostomy, and lower-ureteral high-risk/unfavorable disease in a functional renal unit for distal ureterectomy with reimplant.
• Proximal two-thirds resections fail more often than distal resections; 5-year recurrence-free survival is worse than RNU, but cancer-specific and overall survival are comparable in selected patients.
• Always confirm negative margins by frozen section and excise the entire intramural ureter and orifice for distal tumours.
• Length-gaining maneuvers: psoas hitch (~5 cm), Boari flap (10–15 cm, base ≥2 cm wider than apex, width ≥3× ureteral diameter; contraindicated with a small irradiated bladder), and ileal ureter (20–25 cm ileum, isoperistaltic).
• A formal bladder cuff excision with watertight closure is preferred over transurethral cuff techniques (lower bladder-recurrence risk; allows intravesical chemotherapy).