Complete surgical resection is the primary treatment for female patients with PPRTs, and benign PPRTs can be effectively cured following complete resection. It is advisable to avoid electrosurgical cauterisation, puncture and drainage, and the injection of sclerosing agents for tumours, as these methods are associated with a high recurrence rate and may compromise the anatomical structure of the tumour, thereby increasing the difficulty of subsequent surgeries. In cases where PPRTs are incidentally detected during laparoscopic or open surgical procedures, performing a biopsy should be strictly avoided, as it may damage the anatomical structure, contaminate adjacent tissues and complicate future surgical interventions. It is strongly recommended that patients be referred to a large, comprehensive hospital with relevant experience to mitigate these risks.
The anatomical structure of the pelvic retroperitoneal space is complex and involves the iliac vessels and their branches, nerves, ureters, intestinal tubes and other critical structures. This space has narrow dimensions, necessitating collaboration among multidisciplinary departments, including gynaecology, colorectal surgery, urology and vascular surgery departments. Patients should be referred to a large comprehensive centre for treatment, as the volume of the centre is associated with surgical outcomes.17 Intraoperative tumour rupture and secondary resection have been identified as independent risk factors for the recurrence of presacral benign tumours.18 Furthermore, initial R0 resection represents a pivotal opportunity for potentially curing malignant PPRTs.19 En bloc resection is recommended for malignant PPRTs to achieve R0 resection, which is characterised by local infiltrative growth and distant metastasis.20
Recommendations: Surgical resection is the primary treatment for female patients with PPRTs (category 1); Biopsy should be avoided for PPRTs detected incidentally during laparoscopic or open surgery, and patients should be referred to a large comprehensive hospital with experience (category 2A); Initial complete resection is recommended for female patients with PPRTs because it affects prognosis. En bloc resection is advised for patients with evidence of organ involvement, and combined surgery can be considered by MDT if necessary (category 2A).
Surgical approach
Female PPRTs can be resected through various surgical approaches. The choice of surgical method and extent of resection depends on factors such as the tumour location, size and nature, and the involvement of the pelvic walls or pelvic organs. Additionally, the technical expertise and proficiency of the surgical team should be considered.
Anterior approach (open surgery, laparoscopic surgery, etc)
Open surgery is typically recommended for PPRTs located laterally in the pelvis or posteriorly for pubic or presacral tumours above the S3 vertebra, provided that there is no invasion of the sacrum. Although this approach offers a larger operating space and facilitates the separation of pelvic organs, it presents challenges in addressing the caudal portion of PPRTs.21 Open surgery remains the predominant surgical approach for retroperitoneal sarcoma due to the large size and complex anatomy of the tumour, which may necessitate combined organ resection.22 Notably, visibility during open surgery is limited for tumours located deep within the pelvis.23
Laparoscopic surgery, which involves both conventional laparoscopy and robot-assisted laparoscopy, offers significant advantages for delicate manipulation within the confined space of the deep pelvis. This technique enhances the visualisation of nerves, blood vessels and surrounding tissues, thereby reducing the risk of injury during procedures.24 25 Certain PPRTs, located below the S3 vertebra and above the levator ani muscle, can be completely resected using laparoscopy, thereby broadening the indications for the anterior approach.3 However, there is a lack of consensus regarding the indications for laparoscopic surgery in the treatment of PPRTs. Most studies suggest that laparoscopic intervention is appropriate for small tumours that exhibit no malignant characteristics on imaging and show no significant invasion of adjacent organs or bone. For solid PPRTs, it is advisable that the tumour diameter not exceed 10 cm, although the size may be adjusted on the basis of the complexity of the surgery and the surgeon’s experience. In the case of cystic tumours, the criteria for minimally invasive surgery can be more lenient, as controlled volume reduction of the tumour can be performed intraoperatively.26 Compared with open surgery, laparoscopic techniques have been shown to improve the surgical field and enhance postoperative recovery.1 Notably, robot-assisted laparoscopic surgery offers additional benefits for cases involving previous surgical failure or recurrent tumour resection, providing greater surgical safety and being particularly well suited for intricate procedures.27 28
Recommendations: For solid PPRTs, laparoscopic surgery is recommended for tumours that are small in size, located above the pelvic floor muscle, exhibit benign characteristics on imaging and show no obvious invasion into surrounding organs or the pelvic wall. In contrast, the indications for cystic PPRTs can be relaxed accordingly. Open surgery is advised for PPRTs located above the S3 vertebra, which demonstrate malignant tendencies characterised by a large size, a predominance of solid components and invasion into surrounding organs, as indicated by imaging examinations. (Category 2B).
Posterior approach (transsacral, transsacrococcygeal, transperineal, transvaginal and others)
The posterior approach is the primary surgical technique for type I PPRTs located below S3. This technique may be associated with complications such as perineal infection or sinus formation. Compared with the anterior approach, the posterior approach facilitates access to the caudal portion of the tumour, resulting in shorter operation times, fewer complications and improved incision healing. This approach is particularly suitable for small type I PPRTs located below S3.6 29 However, it is important to note that there is an increased risk of intraoperative pelvic haemorrhage and lateral pelvic nerve injury due to inadequate vascular visualisation. Therefore, it is essential for the surgeon to possess a thorough understanding of the anatomical structures, maintain a clear surgical field and avoid blind compression and excessive traction on the tissues. At the start of surgery, the patient is positioned in lithotomy, and an incision is made either in a curved fashion, following the ‘Mercedes-Benz standard’, or along the lower sacral midline. The external anal sphincter must be preserved during the procedure. The caudal anal ligament is then identified and transected to expose the tumour and separate the lesion from the rectum (mesentery). In cases of benign PPRTs, an identifiable mesorectal fascia typically exists between the mesorectal and retrorectal lesions. The surgeon must take care to avoid iatrogenic injury to the rectum during dissection. This can be facilitated by injecting a water pad to identify the separation gap and placing the index finger or gauze beneath the anal canal and rectum to apply forward pressure. In cases where the rectal wall adheres to the lesion and cannot be safely separated, a portion of the rectal wall may need to be excised along with the lesion. Additionally, the removal of the coccyx may reduce recurrence rates for tumours that are densely adhered to it, although this may result in chronic sacrococcygeal pain postoperatively.21
An intersphincteric approach can be considered for presacral PPRTs that are small in size, exhibit a benign tendency and are located at an extremely low position. At the commencement of the surgery, the patient is placed in a prone or truncated position. An inverted V-shaped or radial incision is subsequently made posterior to the anus to access the intersphincteric plane. The anal canal and internal sphincter are then bluntly separated from the external sphincter up to the level of the puborectalis muscle, allowing entry into the presacral space along the cephalad side, where a combination of sharp and blunt dissection techniques can be employed.
Transvaginal surgery is primarily employed for type II tumours, which are characterised by their small size and low positioning. This surgical approach is considered for tumours located beneath S5, provided that they do not exhibit dense adhesion to surrounding tissues or invasion into the coccyx and that their upper borders are palpable during vaginal or rectal examination. Generally, this technique demands advanced surgical skills due to the limited exposure within the surgical field.30 31
Recommendations: The posterior approach is suitable for type I PPRTs under S3. (Category 2B).
Combined approach
The abdominal approach combined with the sacral approach is typically employed for a type I PPRT with a large volume, characterised by an upper pole positioned higher than S4 and a lower pole closely associated with the sacrococcygeal region. This approach is particularly beneficial for masses that invade surrounding structures such as blood vessels, pelvic sidewalls, the sacrum, the ureter or the rectum.32 The rectum at the anorectal fissure, often referred to as the bare rectal area, poses significant challenges in visualisation and separation during surgical procedures because of its deep location and lack of mesenteric fat coverage, which increases the risk of injury. Throughout the operation, the principle of 'first easy, then difficult’ should be followed. Initially, an anterior approach can be used to separate the cranial aspect of the tumour up to the pelvic floor, providing a well-visualised and larger operating space for the pelvic organs, blood vessels, nerves and other structures. A posterior approach can subsequently be employed to dissect the caudal portion of the tumour beneath the pelvic floor muscles. Consequently, resection of the coccyx via the posterior approach can be minimised through the combined approach, thereby reducing postoperative complications such as caudal fossa effusion, incisional infection and long-term caudal pain.
The laparoscopic approach combined with transvaginal techniques can be considered for type II PPRTs, where the upper border (above S3) cannot be palpated during a triple examination, and the lower border remains below S5 after upward manipulation. Additionally, this approach is also viable for large type III PPRTs located low in the pelvis and in sexually experienced individuals, as it reduces the risk of incision-related complications compared with the abdominal approach combined with the sacral technique.
Recommendations: A combined approach is recommended for female patients with giant PPRTs that cannot be resected by a single surgical approach. (Category 2B).
Surgical complications and treatment
Rectal injury
Rectal injuries are observed predominantly in procedures involving an anterior approach. Tumour resection should be conducted as close to the tumour envelope as possible to minimise the risk of rectal injury. In the event of intraoperative rectal injury, the entire layer can initially be sutured using absorbable sutures, followed by embedding the muscle layer with plasma.24 For cases involving severe injury and inadequate repair, proximal mesenterostomy and the placement of an anal tube may be necessary.
Presacral haemorrhage
Presacral haemorrhage is predominantly observed in type I primary presacral tumours. The presacral venous plexus possesses numerous trafficking branches connecting to the intravertebral venous plexus and lacks venous valves. Notably, the inverted triangle of the venous network located in the anterior region of the S3–S5 vertebrae constitutes the 'danger triangle’ for presacral haemorrhage. Achieving haemostasis in this area is challenging, as the bleeding presacral veins often retract toward the sacral foramen or the cancellous bone of the sacrum. Surgeons should exercise caution to avoid exerting excessive traction on the tumour and surrounding tissues to prevent tearing. Bipolar electrocoagulation of the periosteum is a convenient and effective haemostatic technique, as it can effectively destroy the periosteum.33 Additionally, suture haemostasis may be attempted during a posterior approach. The filling compression method can be employed when other haemostatic strategies prove ineffective; however, caution is warranted, as this method may lead to tearing and other collateral injuries during compression, potentially exacerbating bleeding. For tumours characterised by a rich blood supply, significant volume and complex structure, adequate blood preparation prior to surgery is essential, and prepositioning an abdominal aortic balloon can be beneficial in minimising the risk of intraoperative bleeding.
Nerve injury
Pelvic nerve injury can lead to sensory‒motor disorders of the lower limbs, urinary dysfunction, defecation issues and sexual dysfunction. Posterior approach surgery carries a high risk of lateral pelvic nerve injury due to limited visualisation, whereas nerve injuries during anterior approach surgery often occur during haemostasis. Therefore, minimising intraoperative bleeding is crucial to ensure a clear surgical field. Furthermore, the pelvic nerve plexus is frequently located adjacent to or within the lateral rectal ligament, and excessive stretching of the lateral rectal ligament or rectosacral fascia may damage the branches of the sacral 2–4 parasympathetic nerves that converge into the pelvic plexus, resulting in urinary dysfunction. In the case of PPRTs that envelop nerves, the tumour should be incised longitudinally and carefully separated from the surrounding tissue along the nerve pathway, avoiding any transverse resection of the nerve.
Ureteral injury
The risk of ureteral injury may be increased by ureteral displacement due to compression from a PPRT or by adhesions to the ureter. Intraoperative detection of ureteral injury necessitates prompt intervention. In cases of delayed ureteral injury postsurgery, the treatment approach varies on the basis of the timing of detection; cystoscopy or ureteral stenting should be employed as needed, whereas one-stage repair and reconstruction or percutaneous nephrostomy could be considered appropriate. The preoperative placement of ureteral stents aids in the intraoperative identification of the ureter; however, the impact of this practice on reducing the risk of ureteral injury remains a topic of debate.34 35
Poor incision healing
Poor incision healing is more prevalent in surgeries that use the posterior approach, which can be attributed to several factors. First, the proximity of the sacrococcygeal incision to the anus increases the risk of contamination. Second, the accumulation of blood and fluid beneath the skin postoperatively can result in flap ischaemia, necrosis and subsequent infection. Additionally, the presence of a residual cavity following tumour resection, among other factors, can further impede the healing of the incision. To address these issues, pelvic floor tissues may be reconstructed after tumour resection to eliminate any residual cavities. Furthermore, adequate drainage should be implemented following the surgical procedure.
Anorectal dysfunction
Factors such as damage to the nerve plexus due to tumour compression, compression and traction from surrounding tissues, and surgical trauma may result in a diminished ability to sense defecation in the anorectal area, leading to an inability to fully control defecation. Attention should be directed toward protecting important organs, as well as the pelvic floor nerves and muscles, to avoid tissue damage caused by excessive clearance while ensuring that complete resection is achieved intraoperatively. Furthermore, providing scientific defecation training and dietary guidance and implementing standardised care for the perianal skin in the early postoperative stage are essential.
