Hypothesis / aims of study
There is accumulated evidence to consider adjustable transobturator male system (ATOMS) is an effective treatment for male stress urinary incontinence (SUI), especially in mild to moderate cases (1). Also, high patient satisfaction and limited complication rate can be anticipated according to several studies (2,3).
Significantly better results have been described in the short-term in non-severe and non-radiated cases (1). However, long-term data with this device is lacking. The system is not prone to mechanical failure but durability of the device in the long-term is unknown. Our objective is to evaluate long-term efficacy and safety of ATOMS for male SUI, and also to evaluate durability of the system and factors influencing endurance.
Study design, materials and methods
Retrospective multicentre IRB aproved study conducted in nine Iberian institutions using a board-approved database of 215 consecutive patients updated using an eCRF to periodically evaluate long-term continence status, complications, explants and secondary treatments. Initial outcomes were reported in 2017 (1). SUI severity was defined as mild if baseline pad-count was 1-2 PPD, moderate 3-5 PPD and severe >5 PPD. All patients were updated to March 2020, except for eleven cases deceased of unrelated cause.
Primary objective was evaluation of long-term efficacy by the proportion of patients achieving continence with the implant at last follow-up. Continence at the time of adjustment was defined as SUI with use of none or one security pad/day (PPD) with <10cc urine loss. The same definition was used during follow-up. Kaplan-Meier curve was also performed to investigate evolution of dryness in patients achieving continence after adjustment.
Secondary objective was evaluation of long-term safety and device durability. Complications were registered during follow-up and device explant rate and reasons were evaluated in the total series. Factors affecting explant and consequent recurrence of SUI were evaluated using univariate and multivariate analysis. Kaplan-Meier study and log-rank test were performed to investigate long-term device durability in a real practice setting. Secondary treatments after ATOMS explant were also evaluated, based on investigator decision.
Results
A total of 215 cases were included in the Iberian ATOMS study (1). SUI baseline severity was mild in 50 patients (23.3%), moderate in 106 (49.3%) and severe in 59 (27.4%). Device generation was inguinal port in 34 patients (15.8%), simple scrotal port in 31 (14.4%) and silicone-covered scrotal port in 150 (69,8%). Mean follow-up from surgery to March 2020 was 60.6±18.4 months (range 39-91). Totally 72.1% of the patients remained dry (n=155; 99 (46%) used no pads and 56 (26%) a security PPD). Kaplan Meier analysis revealed that among the population achieving dryness after adjustment (n=173), 96% remained free of SUI 1-year after implant, 93.6% 2-years, 91.1% 3-years, 89.2% 5-years and 86.7% 8-years.
Complications occurred in 43 patients (20%). In order of frequency they included: perineal pain (15 cases), port erosion and infection (10 cases), de novo urge incontinence (4 cases) scrotal hematoma (4 cases), incipient port erosion without infection (2 cases), wound dehiscence (2 cases); and acute urinary retention, wound infection, urinary infection, haematuria, delirium and ictus (1 case each). Three cases (1.4%) received radiation after ATOMS implant without significant complication or malfunction. Perineal pain did not present newly after the initial report; however, all cases with de novo urge incontinence developed later.
Device explant occurred in 25 patients (11.6%). Reasons for explant were device inefficacy (11 cases, 44%), inefficacy and pain (3 cases, 12%), port erosion and infection (10 cases, 40%) and wound infection (1 case, 4%). Secondary implant was performed in 11 (5.1%) cases, artificial urinary sphincter (AUS) in 6 (2.8%) and repeated ATOMS in 5 (2.3%). Device explant was associated to complications (p<.0001), baseline SUI severity (p=.01) and former irradiation (p=.03); but was not related to patient age (p=.39) or device generation (p=.17). Multivariate analysis revealed presence of complications (HR 8.71; 3.83-19.82), irradiation before ATOMS placement (HR 2.26; 0.99-5.18) and baseline severity, moderate compared to mild (HR 8.77, 1.15-66.67) and severe compared to mild (HR 14.92, 1,87-125) were independent factors to determine ATOMS explant. Kaplan-Meier analysis revealed durability of ATOMS was 99.5% 1-yr after implant, 97.2% 2-yrs, 92.6% 3-yrs, 86.3% 5-yrs and 80.4% 8-yrs.
Interpretation of results
The Iberian study gave excellent data to evaluate long-term efficacy, safety and durability of ATOMS device to treat male SUI. This real practice study was performed by the collaboration of eight institutions in Spain and Portugal. Results initially reported at 24-months mean follow-up confirmed ATOMS device was safe and achieved high treatment efficacy and patient satisfaction (1,2). Updated data to 60-month mean follow-up allow a better understanding of long-term device explant and secondary treatments and give a better idea of real-life data regarding long-term safety and efficacy of the device.
Less than 10% decrease in continence rate is proved in the long-term (72.1% compared to 80.5% previously reported) and less than 5% increase in complications rate (20% compared to 15.3%). These data are again reassuring. Patients achieving continence after adjustment may become incontinent again if complications lead to device explant, most often due to port erosion and device infection (3). Perineal pain is the most frequent complication, characteristically present in the first months after surgery, but not later. On the other hand, de novo urge incontinence is typically a late complication, but an infrequent one (1.9%). Further studies with urodynamics data should better define the reason and significance of de novo overactive bladder after ATOMS placement.
Interestingly, this is the first report to address ATOMS durability in the long-term, that appears excellent. ATOMS was explanted in 11.6% and main reasons were infective complications or device clinical inefficacy. In no case device was explanted due to pain exclusively. Infective complications occurred in 5.1% of the cases. Prospective comparison between ATOMS and AUS durability should be performed. In the meantime, the figures given in the Iberian study suggest durability of ATOMS may exceed that of AUS as surgical revisions are rarely needed and explant rate is low in the long-term. Severe baseline incontinence (6 or more PPD) and complications, not only after surgery but also during follow-up, are the most important risk factors for ATOMS explant. Although not so strong, radiation is also an independent factor for explant, probably because of diminished clinical efficacy (1). Two options appear feasible to re-treat SUI after ATOMS explant: AUS and second ATOMS. Possibly, repeated ATOMS is the best choice for patients with good operative results who lost their device for infection and AUS is the best choice for cases with failed ATOMS and severe SUI still motivated to receive a second implant. These data are pioneer to give an idea on clinical management options after ATOMS failure. However, further studies with bigger numbers appear necessary to define optimum secondary treatment options.