Relationship between operative duration and perioperative outcomes after radical cystectomy.

INTRODUCTION Prolonged operative times have been associated with an increased risk in complications in other major abdominal surgeries. This study tests the hypothesis that longer operative times will be associated with an increased risk in perioperative complications after radical cystectomy (RC). MATERIALS AND METHODS: Adult patients who underwent RC from January 1, 2012, through December 31, 2016, were identified from the National Surgical Quality Improvement Program (NSQIP) database. A natural log transformation was used to determine cutoff points for operative times at 33rd, 67th, and 90th percentiles: 272, 371, and 479 minutes, respectively. Cohorts were A (≤ 272 min), B (273-371 min), C (372-479 min), and D (> 479 min). Multivariable logistic regression analysis was performed to identify associations between operative time and perioperative complications. RESULTS: Among 5,610 patients, the distribution across cohorts was A, 1,993 patients; B, 1,818; C, 1,171; and D, 628. Cohort D had a higher incidence of pulmonary embolism (PE), deep vein thrombosis (DVT), urinary tract infection (UTI), sepsis, 30-day readmission, and blood transfusion rate and had a longer median hospital length of stay. Multivariable analysis showed that operative time (per 60 min) was associated with increased risk of DVT (OR 1.10, p = .04), PE (OR 1.15, p = .01), UTI (OR 1.08, p = .004), readmission (OR 1.04, p = .03), and blood transfusion (OR 1.23, p < .001). CONCLUSIONS: Longer operative times during RC are associated with a higher rate of perioperative complications. These findings may be confounded by disease stage, surgeon experience, variations in perioperative management protocols, or a combination of the above.

Variation in Lymph Node Yield After Radical Cystectomy.

OBJECTIVES: To test the hypothesis that lymph node yield will vary by pathology assistant (PA) in patients undergoing radical cystectomy (RC) with pelvic lymph node dissection (PLND). METHODS: This is a single-institution retrospective review that included patients who underwent an RC with PLND for bladder cancer from January 1, 2007, to January 1, 2018. Predicted mean lymph node counts were generated using multivariable regression analysis. RESULTS: In a total of 430 patients who underwent RC with PLND, the median lymph node count (interquartile range) was 15.0 (11.0-21.0). The frequency of the limits of lymphadenectomy was as follows: external iliac, internal iliac, and obturator (true pelvis) (33.3%); true pelvis plus common iliac to the level of the aortic bifurcation (47.9%); and inferior mesenteric artery (18.8%). On descriptive analysis, there were differences in lymph node yield when evaluating the following variables: level of dissection, clinical stage, neoadjuvant chemotherapy, surgical approach, surgeon, pathologist, and PA (P < .05). On multivariable analysis, adjusted lymph node counts varied between surgeons, pathologists, clinical stage, and level of dissection but not by PA (P = .18). CONCLUSIONS: Lymph node yield after RC varies on several known levels, including surgeon, extent of lymphadenectomy, clinical stage, and pathologist. This study found no significant variation in lymph node yield according to PA.

The effect of urinary diversion on long-term kidney function after cystectomy.

OBJECTIVES: Cystectomy with urinary diversion is associated with decreased long-term kidney function due to several factors. One factor that has been debated is the type of urinary diversion used: ileal conduit (IC) vs. neobladder (NB). We tested the hypothesis that long-term kidney function will not vary by type of urinary diversion. METHODS AND MATERIALS: We retrospectively identified all patients who underwent cystectomy with urinary diversion at our institution from January 1, 2007, to January 1, 2018. Data were collected on patient demographics, comorbid conditions, perioperative radiotherapy, and complications. Creatinine values were measured at several time points up to 120 months after surgery. Glomerular filtration rate (GFR) (ml/min per 1.73 m2) was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. A linear mixed model with inverse probability of treatment weighting (IPTW) was used to compare GFR between the IC and NB cohorts over time. Multiple sensitivity analyses were performed based on 2 different calculations of GFR (Chronic Kidney Disease Epidemiology Collaboration equation vs. Modification of Diet in Renal Disease), with and without excluding patients with preoperative GFR less than 40 ml/min per 1.73 m2. RESULTS: Among 563 patients who underwent cystectomy with urinary diversion, a NB was used for 72 (12.8%) individuals. Patients who had a NB were significantly younger, had a lower American Society of Anesthesiologists score, greater baseline GFR, better Eastern Cooperative Oncology Group performance status, lower median Charlson comorbidity index, and were less likely to have received preoperative abdominal radiation (all P < 0.05). Both NB and IC patients had decreased kidney function over time, with mean GFR losses at 5 years of 17% and 14% of baseline values, respectively. The IPTW-adjusted linear mixed model revealed that IC patients had slightly more deterioration in kidney function over time, but this was not statistically significant (estimate, 0.12; P = 0.06). The sensitivity analyses yielded a similar trend, in that GFR decrease appeared to be greater in the IC cohort. This trend was statistically significant when using Modification of Diet in Renal Disease (P = 0.04). CONCLUSIONS: Among highly selected patients with an NB, deterioration of kidney function may potentially be lower over time than among IC patients. However, the statistical significance varied between analyses and we cautiously attribute these observed differences to patient selection.

How the Beneficial Effects of Alvimopan Differ With Surgical Approach for Radical Cystectomy.

OBJECTIVE: To assess whether the beneficial perioperative effects of alvimopan differ with surgical approach for patients who undergo open radical cystectomy (ORC) vs robot-assisted radical cystectomy (RARC). METHODS: This retrospective study reviewed all patients who underwent cystectomy with urinary diversion at our institution between January 1, 2007, and January 1, 2018. Data were collected on demographic characteristics, comorbidities, surgical approach, alvimopan therapy, hospital length of stay (LOS), days until return of bowel function (ROBF), and complications. Outcomes and interactions were evaluated through regression analysis. RESULTS: Among 573 patients, 236 (41.2%) underwent RARC, 337 (58.8%) underwent ORC, and 205 (35.8%) received alvimopan. Comparison of 4 cohorts (ORC with alvimopan, ORC without alvimopan, RARC with alvimopan, and RARC without alvimopan) showed that patients who underwent ORC without alvimopan had the highest rate of postoperative ileus (25.6%, P = .02), longest median hospital LOS (7 days, P < .001), and longest time until ROBF (4 days, P < .001). On multivariable analysis, the interaction between surgical approach and alvimopan use was significant for the outcome of ROBF (estimate, 1.109; 95% confidence interval, 0.418-1.800; P = .002). In the RARC cohort, multivariable analysis showed no benefit of alvimopan with respect to ileus (P = .27), LOS (P = .09), or ROBF (P = .36). Regarding joint effects of robotic approach and alvimopan, RARC had no effect on gastrointestinal tract outcomes. CONCLUSION: We observed a diminished beneficial effect of alvimopan among patients undergoing RARC and a statistically significant benefit of alvimopan among patients undergoing ORC. The implications of these findings may permit more selective medication use for patients who would benefit the most from this drug.

Single-dose perioperative mitomycin-C versus thiotepa for low-grade noninvasive bladder cancer.

INTRODUCTION: Mitomycin-C (MMC) and thiotepa are intravesical agents effective in reducing the recurrence of low-grade noninvasive bladder cancer when instilled perioperatively. No studies have compared these agents as a single-dose perioperative instillation. This study tests whether there is a difference in recurrence-free survival in patients with low-grade noninvasive bladder cancer who received intravesical MMC versus thiotepa. MATERIALS AND METHODS: A retrospective review was performed of patients who underwent cystoscopic excision of a bladder mass identified as a small, low-grade, treatment-naïve, noninvasive, wild-type urothelial carcinoma of the bladder and who received either intravesical thiotepa (30 mg/15 cc) or MMC (40 mg/20 cc) between January 1, 2002, and January 1, 2016. Data were collected for demographic characteristics, comorbid conditions, operative information, surveillance, and recurrence. The primary outcome was disease-free survival. Cohorts were compared via the doubly robust estimation approach, which used logistic regression to model the probability of recurrence. RESULTS: Of 154 total patients, 84 received intravesical MMC; 70, thiotepa. No statistical differences were shown between groups for age, sex, race, body mass index, smoking status, or baseline comorbid conditions; mass size, tumor multifocality, or tumor grade; and unadjusted recurrence rates (MMC, 36.0%; thiotepa, 46.0%; p = .33) at similar median follow up (MMC, 20.4; thiotepa, 22.8 months; p = .46). The robust logistic regression analysis yielded no differences in recurrence rates between MMC and thiotepa (OR, 0.65 [95% CI, 0.33-1.31]; p = .23). No episodes of myelosuppression or frozen pelvis were identified. CONCLUSIONS: As single-dose perioperative agents, both thiotepa and MMC were associated with similar recurrence-free survival rates.

Robotic vs. open cystectomy: How length-of-stay differences relate conditionally to age.

OBJECTIVES: The length-of-stay (LOS) benefit of minimally invasive cystectomy varies in the published literature, potentially because of subgroup effects. Here, we investigated the effect of minimally invasive cystectomy on LOS among different age groups. METHODS AND MATERIALS: Adult patients who underwent cystectomy (open or minimally invasive) from January 1, 2012, to December 31, 2016, were identified from the National Surgical Quality Improvement Program database. Multivariable linear regression was used to evaluate the adjusted association between the surgical approach and LOS after stratifying patients by age (40-64, 65-79, and ≥80 years). A sensitivity analysis was performed after multiple imputation by using age as a continuous variable with a third-order polynomial term. RESULTS: Of the 5,561 patients identified, 640 underwent minimally invasive cystectomy and 4,921 had open cystectomy. The unadjusted analysis showed that minimally invasive cystectomy was associated with a shorter mean LOS compared with the open approach (8.0 vs. 9.7 days; P < 0.001). The predicted difference in LOS between the 2 approaches was 0.72 days (95% confidence interval (CI), -0.28 to 1.72; P = 0.16) for patients aged 40 to 64 years, 1.48 days (95% CI, 0.73-2.23; P < 0.001) for 65 to 79 years, and 2.56 days (95% CI, 0.84-4.29; P = 0.01) for ≥80 years favoring the minimally invasive approach. The sensitivity analysis did not materially change the results. CONCLUSIONS: Older patients may derive more LOS benefit from minimally invasive approaches than younger patients. Given the greater expense associated with the minimally invasive approach, an age-adapted strategy to using this technology may be reasonable.