Fankhauser CD et al, 2018: Extracorporeal shock wave lithotripsy versus flexible ureterorenoscopy in the treatment of untreated renal calculi.

Monday, 31 December 2018

7961 Hits

Fankhauser CD, Hermanns T, Lieger L, Diethelm O, Umbehr M, Luginbühl T, Sulser T, Müntener M, Poyet C.
Department of Urology, University Hospital, University of Zurich, Zurich, Switzerland.
Department of Urology, City Hospital Triemli of Zurich, Zurich, Switzerland.
Department of Urology, Spital Uster, Uster, Switzerland.

Abstract

Background: The reported success rates for treatments of kidney stones with either extracorporeal shock wave lithotripsy (ESWL) or flexible ureterorenoscopy (URS) are conflicting. We aimed to compare the efficacy and safety of ESWL and URS for previously untreated renal calculi.
Methods: All patients treated with ESWL or URS at our tertiary care centre between 2003 and 2015 were retrospectively identified. Patients with previously untreated kidney stones and a stone diameter of 5-20 mm were included. Stone-free, freedom from reintervention and complication rates were recorded. Independent predictors of stone-free and freedom from reintervention rates were identified by multivariable logistic regression and a propensity score-matched analysis was performed.
Results: total of 1282 patients met the inclusion criteria, of whom 999 (78%) underwent ESWL and283 (22%) had URS. During post-operative follow-up, only treatment modality and stone size could independently predict stone-free and freedom from reintervention rates. After propensity score matching, ESWL showed significantly lower stone-free rates [ESWL (71%) versus URS (84%)] and fewer patients with freedom from reintervention [ESWL (55%) versus URS (79%)] than URS. Complications were scarce for both treatments and included Clavien Grade 3a in 0.8% versus 0% and Grade 3b in 0.5% versus 0.4% of ESWL and URS treated patients, respectively.
Conclusions: Treatment success was mainly dependent on stone size and treatment modality. URS might be the better treatment option for previously untreated kidney stones 5-20 mm, with similar morbidity but higher stone-free rates and fewer reinterventions than ESWL.

Clin Kidney J. 2018 Jun;11(3):364-369. doi: 10.1093/ckj/sfx151. Epub 2018 Jan 25. FREE ARTICLE

Comments 1

Peter Alken on Monday, 31 December 2018 16:15

This is a good retrospective study which has the added value of a propensity score-matched analysis of a large case number and thus my serve as a valid reference. The well-known advantages of fUR vs. SWL in regards of stone free rates and reintervention rates are confirmed.
Some details deserve comments:
1.) Both, URS and SWL were performed “under general or regional anaesthesia depending on patient’s preference.” One of the patient and cost orientated advantages of ESWL is the anaesthesia free treatment.
2.)“…the higher stone-free rate after URS would be less game-changing if associated with distinctly higher rates of morbidity. As URS is considered as more invasive than ESWL, the assessment of treatment morbidity is crucial for further comparison of both interventions. In our large cohort study, we found similarly low perioperative morbidity with very few relevant complications (Clavien Grade IIIa or IIIb complications) in both intervention groups”
Morbidity is more than just retreatment or complications. When comparing ESWL with URS the morbidity caused by double-J stents is often neglected. “In case of double J ureter stenting during ESWL, the stent normally remained for 4–6 weeks or longer depending on the clinical course.” “The choice between primary and secondary URS (double J ureter stent 7–14 days before surgery [, done in 45.6% of the URS cases]) was based on the surgeon’s preference “After URS “all patients received a double J ureter stent for 3–10 days.”
No numbers or details are given on this aspect.
3.) The stone free rate after ESWL varied extensively between 40% and 100% in the three months periods from 2013 to 2012 ( Supplementary figure). The author are aware of that problem by stating “The varying stone-free rate observed after ESWL during our study period indicates that additional factors (i.e. detailed and specific settings of the lithotripter, experience of treating physician) are important for successful ESWL treatments.“ A comparable statement for fURS could be: The varying stone-free rate observed after fURS during our study period indicates that additional factors (i.e. detailed and specific settings of the instruments, experience of treating physician) are important for successful fURS treatments, but it is missing because the standards of training and supervision of URS and ESWL are very different.

This is a good retrospective study which has the added value of a propensity score-matched analysis of a large case number and thus my serve as a valid reference. The well-known advantages of fUR vs. SWL in regards of stone free rates and reintervention rates are confirmed.
Some details deserve comments:
1.) Both, URS and SWL were performed “under general or regional anaesthesia depending on patient’s preference.” One of the patient and cost orientated advantages of ESWL is the anaesthesia free treatment. 
2.)“…the higher stone-free rate after URS would be less game-changing if associated with distinctly higher rates of morbidity. As URS is considered as more invasive than ESWL, the assessment of treatment morbidity is crucial for further comparison of both interventions. In our large cohort study, we found similarly low perioperative morbidity with very few relevant complications (Clavien Grade IIIa or IIIb complications) in both intervention groups”
Morbidity is more than just retreatment or complications. When comparing ESWL with URS the morbidity caused by double-J stents is often neglected.  “In case of double J ureter stenting during ESWL, the stent normally remained for 4–6 weeks or longer depending on the clinical course.” “The choice between primary and secondary URS (double J ureter stent 7–14 days before surgery [, done in 45.6% of the URS cases]) was based on the surgeon’s preference “After URS “all patients received a double J ureter stent for 3–10 days.”
No numbers or details are given on this aspect.
3.) The stone free rate after ESWL varied extensively between 40% and 100% in the three months periods from 2013 to 2012 ( Supplementary figure). The author are aware of that problem by stating  “The varying stone-free rate observed after ESWL during our study period indicates that additional factors (i.e. detailed and specific settings of the lithotripter, experience of treating physician) are important for successful ESWL treatments.“ A comparable  statement for fURS could be: The varying stone-free rate observed after fURS during our study period indicates that additional factors (i.e. detailed and specific settings of the instruments, experience of treating physician) are important for successful fURS treatments,  but it is missing because the standards  of training and supervision  of URS and ESWL are very different.

This is a good retrospective study which has the added value of a propensity score-matched analysis of a large case number and thus my serve as a valid reference. The well-known advantages of fUR vs. SWL in regards of stone free rates and reintervention rates are confirmed. Some details deserve comments: 1.) Both, URS and SWL were performed “under general or regional anaesthesia depending on patient’s preference.” One of the patient and cost orientated advantages of ESWL is the anaesthesia free treatment. 2.)“…the higher stone-free rate after URS would be less game-changing if associated with distinctly higher rates of morbidity. As URS is considered as more invasive than ESWL, the assessment of treatment morbidity is crucial for further comparison of both interventions. In our large cohort study, we found similarly low perioperative morbidity with very few relevant complications (Clavien Grade IIIa or IIIb complications) in both intervention groups” Morbidity is more than just retreatment or complications. When comparing ESWL with URS the morbidity caused by double-J stents is often neglected. “In case of double J ureter stenting during ESWL, the stent normally remained for 4–6 weeks or longer depending on the clinical course.” “The choice between primary and secondary URS (double J ureter stent 7–14 days before surgery [, done in 45.6% of the URS cases]) was based on the surgeon’s preference “After URS “all patients received a double J ureter stent for 3–10 days.” No numbers or details are given on this aspect. 3.) The stone free rate after ESWL varied extensively between 40% and 100% in the three months periods from 2013 to 2012 ( Supplementary figure). The author are aware of that problem by stating “The varying stone-free rate observed after ESWL during our study period indicates that additional factors (i.e. detailed and specific settings of the lithotripter, experience of treating physician) are important for successful ESWL treatments.“ A comparable statement for fURS could be: The varying stone-free rate observed after fURS during our study period indicates that additional factors (i.e. detailed and specific settings of the instruments, experience of treating physician) are important for successful fURS treatments, but it is missing because the standards of training and supervision of URS and ESWL are very different.

Cancel Update Comment