Introduction:

Incisional hernias are a frequent complication following minimally-invasive extirpative surgery. Earlier data from open abdominal surgery and an observational study of patients undergoing minimally-invasive prostatectomy suggested that transverse closure could result in a lower incidence of extraction site incisional hernias compared to vertical closure. We sought to compare the incidence of incisional hernias after minimally invasive radical prostatectomy after performing a vertical incision versus a transverse incision for specimen extraction.

Methods:

We conducted a clinically-integrated, crossover, cluster-randomized trial between January 2016 and September 2021 at a single tertiary referral center. Patients aged 21 years or older who were scheduled for minimally invasive radical prostatectomy with a consenting surgeon were included. Surgeons were cluster randomized quarterly for the duration of the trial to either perform vertical or transverse incisions for specimen extraction following minimally-invasive prostatectomy. The primary outcome of interest was the between-group incidence of incisional hernia within 15 months of prostatectomy determined based on physical examination and self-reported patient survey data. Sensitivity analyses using alternative levels of evidence for the diagnosis of incisional hernia were performed.

Results:

1,356 patients (n=705 treated by a surgeon assigned to vertical and n= 651 treated by a surgeon assigned to transverse incisions) participated in this randomized trial, Table 1. Overall, using an inclusive definition of hernia combining clinical examination and survey data, 197 (20%) patients developed an incisional hernia within 15 months of surgery, 797 did not have an incisional hernia within this period, and 362 had missing outcome data regarding incisional hernia. A logistic regression with surgeon included as a random effect was created for each outcome. The main analysis found no significant difference in hernia rates between the two incision types (absolute between-group difference 1.8%, 95% confidence interval -3.4%, 6.6%, p=0.5), Table 2. All 3 sensitivity analyses consistently mirrored these results. Notably, the inclusive definition of hernia use is suitable for comparison between arms, but cannot be used as an estimate of the true prevalence of incisional hernia after minimally invasive prostatectomy.

Conclusion:

Surgeons should choose the incision and closure approach they are most comfortable with when extracting specimens. Studies of modifications to surgical technique are best conducted as randomized comparisons and the clinically-integrated, crossover cluster randomized trial allows large trials to be completed at a single center and at low cost (NCT01407263).

Funding: N/A