Clinical prostate score (CLIPS) [1] is a novel method sensitive for predicting bladder outlet obstruction (BOO) without the need for invasive methods such as urodynamics studies. In our previous study, CLIPS was used to measure voiding functions for patient going for MIST [2]. In a recent publication, Ito et al proposed several predictive factors to determine prostate surgery outcomes [3].
Our aim was to correlate the effectiveness of CLIPS when compared to other adjuncts for BOO such as IPSS score, for patients who have undergone MIST of the prostate.
Study design, materials and methods
148 LUTS patients were recruited prospectively for MIST of the prostate (either prostate UroLift system or transurethral ablation of prostate (REZUM) between 2020 to 2022. They were reviewed at 3, 12 and 24 months with assessment of prostate volume (PV), IPSS, Quality of life (QoL) and international index of erectile function (IIEF) questionnaires and uroflow parameters (maximum flow rate (Qmax), voided volume (VV) a post void residual (PVR)). Analysis was performed after patients were stratified according to CLIPS. Patient had no BOO if 3*Qmax was greater than PV and BOO if 3*Qmax was less than PV. We also examined IPSS change from baseline. Analysis was done using student t-test.
Results
Table 1 showed patients stratified according to CLIPS with PV less or greater than 40cc. There were significant differences for Qmax, and CLIPS at 3, 12 and 24 months (p<0.0001) following MIST between the 2 groups regardless of PV. Voided volume was much better for patients with PV <40cc and for patients with no BOO. IPSS showed no significant differences regardless of prostate size with CLIPS stratification.
There was significant improvement in IPSS when comparing IPSS < 16 or > 16 between the non-obstructed and obstructed groups at 3 months (IPSS<16: -11.15±6.79 and 4.50±10.73 p<0.0001 vs IPSS>16: -8.23±9.95 and 3.83±9.24, p=0.00095), 12 months (IPSS<16: -11.12±6.08 and -0.40±2.97, p-0.0007 vs IPSS>16: -6.86±8.84 and 2.88±11.48, p=0.00111) and 24 months (IPSS<16: -6.79±9.31 and 0.71±3.55, p=0.0558 vs IPSS>16: -12.18±5.08 and 2.14±8.24, p=0.0003), see Figure 1. Patient had improvement in IPSS at (81.2%) 3 months if IPSS <16, (85.5%) 12 and (80.8%)24 months and worsening symptoms at (50%) 3, (23.1%) 12 and (57.1%) at 24 months if IPSS >16.
Interpretation of results
CLIPS can be used to predict the possible outcome of MIST of prostate especially using maximum flow rate and changes in IPSS score. A smaller prostate <40cc and IPSS <16 have better surgical outcome compared to a larger prostate and IPSS >16.
Concluding message
CLIPS can be used as a useful adjunct for predicting success in minimal invasive surgical therapy (MIST) of the prostate. A larger study would be needed to validate this.
Patient stratified according to Clinical Prostate Score CLIPS) and Prostate Volume following Minimal Invasive Surgical Therapy of the Prostate
IPSS Changes after MIST
References
1. Rosier et al. ICS 2021
2. Tsang et al. EAU 2023
3. UPSTREAM trial. European Focus 2023
