In this case, a solitary fibrous tumour invading the retroperitoneum from the vulva was treated successfully by a combined abdominal-sacral approach after embolisation, without a need of blood transfusion. To our knowledge, this is the first case report of the resection of a vulvar SFT through a combined abdominal-sacral approach.
SFTs are rare soft tissue tumours that commonly arise in the pleura [1]. Such tumours rarely arise from the female genital tract, although they have been reported in various other organs. Nine percent of SFTs occur in the female genital tract, and only 42 cases, including several in the retroperitoneum, have been reported so far [5, 6]. Furthermore, only 11 cases of vulvar SFTs have been reported [7]. The management of vulvar SFTs is controversial: The prognosis depends on complete resection of both extrapleural and pleural SFTs [5], but surgery is difficult because of frequent intraoperative heavy bleeding, which occurs because SFTs in the pelvis are usually supplied with blood by multiple vessels, such as the branches of the inferior mesenteric artery or the internal iliac arteries [8, 9]. Therefore, it is necessary not only to ensure a sufficient blood supply but also to control bleeding during surgery.
Because the tumour extended from the vulva into the pelvis, we performed the surgery through a combined abdominal-sacral approach out of concern about the difficulty in establishing an appropriate surgical field deep inside the pelvis by laparotomy. For that reason, we first separated the tumour from the right side of the rectum and uterus through a transabdominal approach and then successfully resected the tumour through a transsacral approach. Most patients with pelvic SFTs have undergone laparotomy, but some patients suffer heavy bleeding, which is difficult to control [9, 10]. In one report, massive bleeding was not avoided even with the transperineal approach [11]. Katsuno et al. reported that the transsacral approach was useful for complete resection of pelvic SFTs [12]; however, this approach carries a high risk of postoperative complications, such as surgical site infection and anal dysfunction [13]. In another report, surgery with a combined abdominal-sacral approach was performed for five cases of giant presacral tumours, and complete resection without massive bleeding was achieved. The advantages of this approach are that complications are minimised and it allows for complete resection of a tumour that may be difficult to remove through other approaches [14]. Thus a combined abdominal-sacral approach can be an option for resecting tumours deep in the pelvis.
We embolised feeder vessels to the tumour before surgery to reduce intraoperative bleeding. Preoperative percutaneous arterial embolisation allows for safe and complete resection in cervical, thoracic and lumbar locations in the spinal cord [15, 16]. Embolisation for pelvic SFT has been reported; Soda et al. reported that a tumour was resected after blood flow block was achieved by an intraoperatively inserted aortic balloon catheter, and the resulting blood loss was 13,660 mL [9]. On the other hand, in other reports, the feeder vessels of SFTs were selectively embolised before operation, which resulted in less intraoperative blood loss without the need for blood transfusion [11, 17, 18]. In addition, in two reports, preoperative embolisation did not have the effect of shrinking the tumour [17, 18]. In our case, it was possible to complete surgery without blood transfusion by performing preoperative embolisation. Therefore, embolisation may control intraoperative bleeding, but it is not effective in reducing tumour volume. In addition, selective embolisation of the feeding vessels is more appropriate than intraoperative aortic occlusion.
We completely resected a vulvar SFT without blood transfusion. This tumour is very rare, nonmetastatic and characterised by abundant blood vessels. The main treatment for SFTs is surgical resection. However, pelvic SFTs carries the risk of massive bleeding and organ damage, and inadequate tumour resection can lead to local recurrence. Preoperative embolisation of feeder arteries reduced intraoperative bleeding in our patient. In addition, use of the abdominal-sacral approach can reduce perioperative complications. This combination thus has potential in the treatment of pelvic SFTs.