Nephroureterectomy

Introduction

Upper tract urothelial carcinoma (UTUC) accounts for 5% to 10% of urothelial cancer, with approximately 60% muscle invasive at the time of diagnosis. Extirpative surgery, traditionally open nephroureterectomy, was considered the gold standard curative procedure. Robotic-assisted radical nephroureterectomy (RANU) has been shown to have equivalent oncological outcomes while benefiting from the advantages of minimally invasive surgery with reduced blood loss and shorter length of hospital stay. RANU also allows for more precise dissection of tissue planes for the distal ureterectomy and a wide bladder cuff for distal ureteric tumors when required. The surgeon can be confident that the whole length of the ureter is taken down to the bladder along with its opening into the bladder.

Indications/contraindications

UTUC can present as either disease of the renal pelvis or proximal ureter, distal ureter, or panurothelial. Low-risk UTUC must include all of the following factors :

• Unifocal

• Tumor size less than 2 cm

• Low-grade cytology

• Noninvasive on computed tomography (CT) urography

• Low-grade ureteroscopic (URS) biopsy

In low-risk disease, consideration of kidney-sparing surgery, endoscopic management, segmental resection, or rarely a percutaneous approach may be offered. Other indications where one may wish to avoid a radical extirpative approach includes a solitary kidney, bilateral disease, palliation, renal insufficiency, high surgical risk, and patient preference.

Patients with high-risk tumors limited to the distal ureter may be offered a distal ureterectomy. This can be performed as an open, minimally invasive, or robot-assisted laparoscopic procedure. In all other cases, a RANU may be offered for UTUC.

Contraindications for RANU include invasive or large (T3/T4 and/or N1/M1) tumors because the oncological outcome is worse compared with an open approach.

Preoperative assessment

Older patients or those with significant comorbidities should undergo medical assessment and optimization of fitness and preparation for radical surgery.

Up to date staging investigations should be completed within 2 months of the date of surgery. This includes a complete staging narrow slice (2 mm) contrast-enhanced CT of the chest, abdomen, and pelvis for full staging, to exclude metastases, locally advanced disease, or involvement of hilar lymph nodes. A delayed urographic phase is essential to diagnose and characterize the renal pelvic or ureteric tumor. This often presents on CT as a filling defect. Sensitivity of UTUC on CT imaging is 92%. Multifocality of the tumor can also be reviewed because this will impact on surgical planning and potential approach.

Magnetic resonance urography (MRU) is indicated in those patients unable to undergo CT urography, usually when radiation or iodinated contrast media is contraindicated. MRU has a sensitivity of 75% after gadolinium contrast injection for tumors less than 2 cm.

Cystoscopic evaluation of the lower urinary tract is essential to rule out a concomitant urothelial tumor that would potentially alter the discussion with and management options for the patient. Abnormal cytology may indicate high-grade UTUC in the presence of a normal bladder cystoscopy with no evidence of bladder or prostatic carcinoma in situ.

Diagnostic URS ± biopsy using a semirigid and flexible ureterorenoscope to evaluate the ureter, renal pelvis, and collecting system allows the determination of the size, appearance, and volume of the tumor burden. Selective urine cytology may be used if imaging and cytology are not sufficient for the diagnosis and risk stratification of the tumor. Barbotage urine cytology has been shown to detect up to 91% of UTUC cancers, being as effective as biopsy histology.

Staging and risk categorization for surgical planning are performed with information from the radiological imaging, renal function, cytology, ureteroscopy, histopathology, and existing comorbidities. Any single risk factor outlined in Fig. 21.1 would result in high-risk stratification.

Stages of procedure