A Comparative Analysis of Complications After Robot-Assisted Radical Prostatectomy for Men Aged ≤69 and ≥70 Years

Introduction

Prostate cancer is the most commonly diagnosed cancer and the second most common cause of American male cancer death. ¹ Treatment options for localized prostate cancer include radical prostatectomy, radiation, and focal therapy. Robot-assisted radical prostatectomy (RARP) has quickly replaced open radical prostatectomy as the preferred surgical approach in both the academic and community settings. ² Multiple studies have reported complication rates for robotic versus open prostatectomy ^{3 –7} and the impact of surgeon experience or learning curve on perioperative outcomes. ^{8 –13} However, literature is lacking on the effect of advanced age on complication rates in men undergoing robotic prostatectomy. Given the increasing male life expectancy and the trend for older men to have more advanced prostate cancer, ^14,15 they may not be ideal candidates for active surveillance. Consequently, reporting complications in this group of patients is particularly relevant. Therefore, in this study, we sought to evaluate the impact of advanced age on complication rates in our initial consecutive series of 1000 RARPs.

Materials and Methods

We analyzed 1000 consecutive patients who were prospectively followed with IRB approval (HS 1998–1984) and who underwent RARP by a single surgeon (T.A.) from 6/2002 to 6/2011. ¹³ No patient received neoadjuvant systemic therapy. Three patients underwent salvage RARP for radiation failure. Patients were followed by postoperative clinical evaluation or by telephone communication within 3 weeks from surgery and thereafter for a median 38.7 months (range 1–113 months). The percentage of patients with ≥1, ≥2, ≥3, ≥5, and ≥7 years of follow-up was 84.5%, 65.3%, 52.2%, 29.7%, and 7.6%, respectively.

Clinical and pathologic data recorded for each patient are listed in Table 1. Information on intraoperative, early, and late complications was collected. Early complication was defined as occurring within 30 days from surgery, and late complication was defined as occurring beyond 30 days from surgery. The Clavien–Dindo classification system ¹⁶ was used to grade the severity of postoperative complications. Complications graded as Clavien ≤2 and ≥3 were considered minor and major complications, respectively. Complication rates were compared between men ≤69 and ≥70 years. In addition, we compared complication rates between men <75 and ≥75 years. The Fischer's exact test was used to compare complications between groups, and a p-value of <0.05 was considered statistically significant.

Results

Of our initial 1000 patients, three were excluded due to insufficient data or prostatectomy performed for BPH (n=997). Patient characteristics for the two cohorts, men ≤69 and ≥70, are displayed in Table 1. The younger men had significantly lower I-PSS and higher SHIM scores. The older men had significantly more advanced cancers with higher Gleason scores and pathologic T stage.

Intraoperative and postoperative complications are listed in Tables 2 and 3, respectively. There were 9 (0.90%) intraoperative complications with no significant difference between the two age groups (p=1) (Table 2). Overall, there were 102 (10.2%) postoperative complications in the entire cohort. Of the early complications, 3.9% (n=39) and 6.9% (n=69) were low (Clavien ≤2) and high (Clavien ≥3) grade, respectively (Table 2). All of the late complications (n=63) were major (Table 2). There were no deaths.

Although there was no statistically significant difference in individual postoperative complications between the two groups, the overall postoperative complication rates for men ≤69 and ≥70 were 9.4% and 15.4%, respectively (p-value=0.042). Multiple complications occurred in seven (0.8%) of the younger and in five (3.9%) of the older men. Major complication rates for men ≤69 and ≥70 were 6.7% (58) and 10.9% (14), respectively (p=0.10); minor complication rates were 2.5% (22) and 4.7% (6), respectively (p=0.25). Extraction port-site hernia and fossa navicularis stricture were the most common complications in both groups.

We also examined if men ≥75 were at greater risk of developing complications. Overall, there were 8 (25%) complications in the 32 men in this subgroup: 3 hernias, 1 rectal injury, 1 anastomotic leak, 1 hematuria with clot retention, 1 fossa navicularis stricture, and 1 bladder neck contracture. None of these categories had any significant difference between men <75 and ≥75 years.

Discussion

We report the complication rates for men ≥70 undergoing RARP in comparison to men ≤69 years. There were no statistically significant differences in intraoperative, individual postoperative, minor, and major complication rates between men ≤69 and ≥70 years. However, the overall complication rates between the two groups were statistically significant, although by a slim margin. These results demonstrate that RARP can be performed relatively safely in this older group of patients, when clinically appropriate. Therefore, the risk of intraoperative or postoperative complications should not deter urologists from offering surgery to men ≥70 years with significant disease and a reasonable life expectancy. Other considerations in this age group include side effects, such as potency and continence, as well as oncologic outcomes. The literature has demonstrated mixed results regarding continence rates in patients ≥70 compared with men ≤70 years, ^14,15,17 and potency rates in men ≥70 range from 30% to 40%. ^{17 –19} Also, men ≥70 have durable disease-specific survival that is similar to younger men. ^{14,15,17 –21}

As previously reported, half of the intraoperative and early complications, as well as 25% of the late complications occurred in the first 200 RARP patients from 2002 to 2004. ¹³ Of note, several noteworthy technical changes were made during our early robotic prostatectomy experience to reduce complications beyond the simple learning curve. ¹³ Two of the Clavien grade 3 complications, fossa navicularis stricture and extraction port-site hernia, comprised nearly 50% of the complications overall, however, both were significantly reduced with technical changes. Our initial use of 22F catheters to prevent stapling of the urethra during control of the dorsal venous complex (DVC) was associated with nearly a 10% risk of catheter-induced fossa navicularis stricture. Since using smaller 16F or 18F catheters, we reduced this complication to <0.5% rate in the last 850 cases. ²² We also no longer staple the DVC, instead we suture ligate the DVC after transecting the urethra. To reduce extraction port-site hernias, we changed the incision for the camera port (prostate removal site) from a vertical to a horizontal incision. Based on evidence that increased tension may be placed on a vertical fascial incision ^23,24 compared to a horizontal one, we changed the orientation of our incision. This technical change has reduced our hernia rate from 4.9% (36/735) to a 0.4% (1/265). Using foam-based safety goggles (SunMed iGuard #9-0210-00, cost 5 US dollars) over the patient's eyes during surgery and for ∼90 minutes in the recovery room reduced corneal abrasions from 2% to 0.1%.

Limitations of this study include an under-reporting of complications due to loss of follow-up. Unlike the overall complication rates, there is limited power to detect age differences in single complication rates due to their low frequencies. Complications that are asymptomatic may not be recognized and, therefore, not reported. The lack of significant differences in complications between men ≥75 and younger men may be related to the small number of men in the older age group. Also, the Charlson comorbidity index, which may play a role in the increased risk of complications in older men, was not available for analysis. Nevertheless, it is important to provide data regarding the safety of this procedure by reporting perioperative complication rates in older men undergoing RARP.

Conclusion

In our study, men ≥70 had a significantly higher overall complication rate after RARP compared with men ≤69 years, however, the individual, minor, and major complications were not different between the two groups. RARP, when clinically appropriate, is relatively safe in this older age group. Identifying complications and proposing insightful working solutions have decreased both minor and major complication rates after RARP.