Endoscopic Management of Low-Grade Upper Tract Urothelial Carcinoma: Characterizing the Long-term Burden of Care in Comparison to Radical Nephroureterectomy.

OBJECTIVE: To compare procedure burden, oncologic, surgical and renal-function outcomes between patients with low-grade upper urothelial cancer (UTUC) who were referred for either radical management (RM) or kidney-sparing endoscopic management (EM). PATIENTS AND METHODS: We retrospectively reviewed data of all patients treated for UTUC at our tertiary medical center between 2000 and 2018 and selected patients diagnosed with unilateral low-grade UTUC. RESULTS: Twenty-four patients were treated with EM and 37 with RM. Surgical and oncologic risk factors were similar between the arms except for tumor size. Mean follow-up was 4.9 ± 3.4 years. The 5-year overall-survival rate was 85% with EM and 84% with RM (P = .707). Metastasis-free and cancer-specific survival were also similar (P = .994, P = .960). End-of-follow-up average glomerular filtration rates were 58.7 ± 21.5 and 49.2 ± 22.1 mL/min/1.73 m2, respectively (P = .12). Ninety-two percent of patients managed endoscopically had local recurrences, with an average of 3.2 recurrences per patient. Four (17%) patients underwent salvage radical nephroureterectomy. Procedure burden was higher with EM, having 6.5 ± 4.4 operations and 344 ± 272 minutes under anesthesia compared with 1.9 ± 0.4 operations (P <.0001) and 213 ± 84 minutes under anesthesia (P = .031) with RM. Cost-of-care analysis revealed higher costs for EM in both private and publicly funded medical insurance plans. CONCLUSION: Patients undergoing endoscopic management had an 83% chance of preserving their kidney and an 81% chance of 5-year metastasis-free survival at a cost of 6.5 ± 4.4 operations during a mean follow-up of 4.9 ± 3.4 years. Our findings support EM for low-grade UTUC as a valid option from oncological aspects but highlight the associated costs.

How Reliable Is the Intraoperative Assessment of Residual Fragments During Percutaneous Nephrolithotomy? A Prospective Study.

OBJECTIVES: To determine the accuracy of the surgeon's impression as to the stone-free rate at the end of percutaneous nephrolithotomy (PCNL), and to evaluate predictors for inaccurate estimation. MATERIALS AND METHODS: A prospective study conducted between 2010 and 2015. Surgeon's impression, categorized as "insignificant residual fragments (RFs)" (<4 mm) or "significant RF" (>4 mm), was recorded at the end of PCNL, and was compared with postoperative imaging results, using CT or a combination of US and kidney, ureter, and bladder radiograph for radiolucent and radio-opaque stones, respectively. The association between missed significant RF and the patient and operative variables was evaluated with univariable and multivariable logistic regression analysis. RESULTS: The study cohort included 312 patients. Significant RFs were found in 75 (24%) patients, comprising all 22 patients in whom RFs were suspected (100%) and 53 patients who were considered stone free (18.6%). The sensitivity, specificity, and positive and negative predictive value of the surgeon's estimation for the absence of significant RFs were 100%, 39%, 0.83, and 1 for radiopaque stones, and 100%, 12.5%, 0.75, and 1 for radiolucent stones. On multivariate analysis, multiple stones (OR = 4, 95% CI: 1.85-8.7, p < 0.001) and cumulative stone size (OR = 1.04, 95% CI: 1.02-1.1, p = 0.005) were independent predictors for missed RFs. CONCLUSION: In approximately fifth of the patients undergoing PCNL, the surgeon's impression of "insignificant RF" may be inaccurate. Stone size and number were independently associated with higher miss rate. These data should be shared with the patients when the postoperative drainage method and the option for an auxiliary procedure are discussed.

Interpreting the results of chemical stone analysis in the era of modern stone analysis techniques.

INTRODUCTION AND OBJECTIVE: Stone analysis should be performed in all first-time stone formers. The preferred analytical procedures are Fourier-transform infrared spectroscopy (FT-IR) or X-ray diffraction (XRD). However, due to limited resources, chemical analysis (CA) is still in use throughout the world. The aim of the study was to compare FT-IR and CA in well matched stone specimens and characterize the pros and cons of CA. METHODS: In a prospective bi-center study, urinary stones were retrieved from 60 consecutive endoscopic procedures. In order to assure that identical stone samples were sent for analyses, the samples were analyzed initially by micro-computed tomography to assess uniformity of each specimen before submitted for FTIR and CA. RESULTS: Overall, the results of CA did not match with the FTIR results in 56 % of the cases. In 16 % of the cases CA missed the major stone component and in 40 % the minor stone component. 37 of the 60 specimens contained CaOx as major component by FTIR, and CA reported major CaOx in 47/60, resulting in high sensitivity, but very poor specificity. CA was relatively accurate for UA and cystine. CA missed struvite and calcium phosphate as a major component in all cases. In mixed stones the sensitivity of CA for the minor component was poor, generally less than 50 %. CONCLUSIONS: Urinary stone analysis using CA provides only limited data that should be interpreted carefully. Urinary stone analysis using CA is likely to result in clinically significant errors in its assessment of stone composition. Although the monetary costs of CA are relatively modest, this method does not provide the level of analytical specificity required for proper management of patients with metabolic stones.