Single-Center Crossover Trial Boosts Surgical Technique Studies

Incisional hernias often occur after minimally invasive extirpative surgeries. The previous studies from open abdominal surgeries and observations from minimally invasive prostatectomies indicated that using a transverse closure might reduce the likelihood of developing an incisional hernia at the extraction site compared to using a vertical closure.

Surgery for prostate cancer may lead to the development of incisional hernia and to understand the impact of incision type on post-operative hernia development, Christopher D Gaffney and his research group conducted a study comparing the outcomes of minimally invasive radical prostatectomy. To track the incidence of incisional hernias in different groups, they divided the patients undergoing the procedure into two groups: one receiving a vertical incision for specimen removal and the other receiving a transverse incision.

Researchers integrated clinical aspects into a crossover, cluster-randomized trial at a single tertiary referral center. Inclusion criteria comprised patients aged 21 years or older scheduled for minimally invasive radical prostatectomy with a consenting surgeon. Surgeons were cluster-randomized quarterly throughout the trial to either employ vertical or transverse incisions for specimen extraction post-minimally-invasive prostatectomy. 

The primary focus of the trial was on comparing the incidence of incisional hernia between the two groups within 15 months post-prostatectomy, assessed through physical examination and self-reported patient survey data. The sensitivity analyses, incorporating alternative levels of evidence for incisional hernia diagnosis, were also conducted.

In this randomized trial, 1,356 patients participated, with 705 treated by surgeons assigned to vertical incisions and 651 treated by those assigned to transverse incisions. When considering an inclusive definition of hernia using both clinical examination and survey data, 197 patients (20%) developed incisional hernias within 15 months of surgery, while 797 did not experience hernias during this period. However, 362 patients had missing outcome data regarding incisional hernia. 

Utilizing logistic regression with the surgeon included as a random effect for each outcome, the main analysis revealed no significant difference in hernia rates between the two incision types (absolute between-group difference 1.8%, 95% CI -3.4%, 6.6%, P=0.5).

 All three sensitivity analyses consistently replicated these results. It’s important to note that the inclusive definition of hernia is suitable for comparing between arms but cannot be utilized as an estimate of the true prevalence of incisional hernia after minimally invasive prostatectomy.

The result concluded that surgeons are advised to opt for the incision and closure approach that aligns with their comfort and expertise when performing specimen extractions. When investigating modifications to surgical techniques, randomized comparisons are deemed optimal. The clinically-integrated, crossover cluster randomized trial stands out as an effective method, enabling the completion of substantial trials at a single center and with minimal costs.

This study is sponsored by Memorial Sloan Kettering Cancer Center.

Source: https://suo-abstracts.secure-platform.com/a/gallery/rounds/18/details/2856

Clinical Trial: https://clinicaltrials.gov/study/NCT01407263

Gaffney CD, Vertosick EA, Laudone V, et al. “Transverse versus Vertical Extraction Site Incision after Minimally Invasive Radical Prostatectomy: A clinically integrated, crossover cluster randomized trial.” Presented at SUO 2023. (Poster: 220)