This retrospective study was approved by the Ethics Committee of our institution (2020-1-096) and conformed to the provisions of the Declaration of Helsinki. The study included 20 patients who underwent TPES for primary and recurrent rectal cancers in the Department of Gastroenterological Surgery at Aichi Cancer Center Hospital (Nagoya, Japan) between January 2004 and April 2020. Among the 20 included cases, seven involved primary lesions, while 13 involved recurrent lesions. All patients were confirmed to have adenocarcinoma.
“Post TPES” was defined as preservation of the bladder with removal of the other pelvic organs (i.e., rectum, uterine adnexa, and a portion of the sacrum). In contrast, “Total TPES” was defined as removal of all pelvic organs, including the bladder, rectum, uterine adnexa, prostate, and a portion of the sacrum.
We conducted a review of the hospital records to obtain the following clinicopathological information for each patient: sex (male or female), age (≥60 or <60 years, median: 60 years), body mass index (BMI, ≥23 or <23 kg/m2, median: 23 kg/m2), neoadjuvant therapy (presence or absence), surgical procedure (Post TPES or Total TPES), location of sacral resection (“Upper”, defined as resection above the level between the 3rd and 4th sacral segment, or “Lower”, defined as resection below the level between the 3rd and 4th sacral segment), operative time ( ≥750 or <750 min, median: 750 min), operative bleeding ( ≥3,000 or <3,000 ml, median: 3,000 ml), complications with a Clavien–Dindo grade higher than III4 (presence or absence), and curability (R0 or R1).
We retrospectively evaluated short-term outcomes in terms of these clinicopathologic factors as well as the efficacy of our TPES technique.
Statistical analysis
All data are expressed as the mean ± SD. The Fisher exact probability test, univariate logistic regression, and multivariate stepwise logistic regression were subsequently performed to identify factors that may influence clinicopathologic variables. The log-rank test was used to evaluate differences in the overall survival rate and disease-free survival rate. The level of statistical significance was set at p < 0.05.
TPES technique
In our surgical strategy for TPES, the level of sacrectomy is confined below the 2nd sacral segment. Sacrectomy performed at very high levels (i.e., resection above the level between the 1st and 2nd sacral segments) is not indicated due to the risk of destabilizing the pelvis.
Our surgical strategy for TPES includes three important aspects: (1) preventing injury to the ureter, (2) ensuring an adequate surgical margin, and (3) stopping unexpected cases of massive bleeding. Notably, the surgical technique is more difficult to employ in cases of recurrent lesions than in cases of primary lesions.
Preventing injury to the ureter
Adhesion is more severe in patients with recurrent lesions than in those with primary lesions, and severe adhesion may precipitate dislocation of the pelvic organs. Notably, the ureters are often dislocated in recurrent cases, and it is difficult to recognize some organs, especially the ureter itself. Therefore, we devised the following approach. As it is critical to preserve the length of the bilateral ureters as much as possible, our technique involves catheterization of double J-stents into the ureters preoperatively, which facilitates recognition of the ureters via palpation during the operation.5
Ensuring an adequate surgical margin
Severe adhesion can make it difficult to differentiate tumor lesions from normal organs, especially during sacral resection. However, it is of paramount importance to ensure an adequate operative field around the sacrum. Colon resection, total mesorectal excision, and central lymph node dissection are then performed, following which the Santorini venous plexus is ligated using the “Bunching technique.” The sacral incision line is marked at least 1 cm apart from the tumor using stunning Kirschner wires. The tip of the Kirschner wires penetrate the posterior gluteal skin. Subsequently, the location of the Kirschner wire in terms of sacral level is determined via roentgenography (Figure 1).
Next, the patient is transferred to the prone position, and the surgical team confirms that the tips of the Kirschner wires protrude through the gluteal skin and sacrum (Figure 2). Incisions are then made at cutaneous sites located more cephalad than the extrusions of the Kirschner wires, and the surgical team ensures that the tips of the wires protrude through the sacrum (Figure 3). This method is used to ensure an adequate surgical margin, following which the bilateral sacrotuberous ligament and sacrospinous ligament are incised (Figure 4). Extrusion of the Kirschner wires is reconfirmed, the cephalad region of the sacrum is resected using a luer or chisel, and the tumor is removed (Figure 5). Thereafter, the bilateral ureters are anastomosed into the ileum and ileal conduit, and a colostomy is created.
Stopping unexpected cases of massive bleeding
Normally, energy devices such as LigaSure™ are used to stop bleeding. However, in cases of recurrence, massive unexpected bleeding is difficult to stop using such devices because of the fragility of the vessel walls due to severe adhesion. Therefore, in our technique, the bleeding point is compressed using gauze balls (Tsupperu), and transfixation suturing is performed using an absorbable synthetic monofilament suture (PDS®) (Figure 6).