Patients with presacral neuroendocrine tumors are often asymptomatic because the tumor is typically indolent and patients have usually already developed metastases at the time of diagnosis [2]. In cases of suspected malignancy in presacral masses, we refrained from performing ultrasound-guided aspiration biopsy to determine the nature of the tumor. This was done to avoid the risk of malignant cell dissemination and metastasis, as well as potential infection that may arise from blind puncture or drainage prior to surgery[3; 4; 5]. In addition, preoperative MRI is highly specific in detecting the involvement of tumor blood vessels and pelvic sidewalls, making it a valuable tool for diagnosing heterogeneous retrorectal tumors[6]. 68Ga-DOTA-TATE PET/CT is a non-invasive tool that can effectively assess tumor heterogeneity, particularly in G2 and G3 NET, and aid in individualized patient management[7],we also adopted this approach postoperatively. The presence of glandular epithelium in the presacral mass is a probable cause of many of these tumors, as there is no apparent source of neuroendocrine cells in the presacral area[8] .
Whether the presacral mass is malignant or not, it is highly beneficial for the patient to undergo an en-bloc resection, maximizing the potential for positive outcomes [9; 10; 11; 12]. When performed by a highly experienced surgeon, the trans-sacral access method is both safe and effective for patients with presacral tumors located below the sacral 3 level. [13]. Presacral tumors are often closely connected to the rectal wall and cannot be distinguished, which leads to some degree of damage to the rectal wall during complete tumor resection. Therefore, it is necessary to avoid postoperative intestinal fistula and presacral infection, and a small intestine or colonostomy is necessary[14; 15]. With the progress of surgical technology, laparoscopic and robot-assisted transabdominal surgery or a combination of abdominal and perineal surgery are also viable options for the treatment of sacral tumors [16; 17; 18].
The powerful oral kinase inhibitor sulfatinib showed anti-angiogenic and anti-tumor action by selectively targeting VEGFR , FGFR1 and CSF1R[19], and has now completed a phase III clinical trial. It has shown good therapeutic results for advanced non-pancreatic neuroendocrine tumors[19; 20; 21]. The drug was able to hinder the development of the tumor in our situation. Complications associated with Sulfatinib include hepatic and renal impairment, hypertension, bleeding, gastrointestinal perforation, and delayed wound healing. Unfortunately, the patient in our report experienced multiple complications, leading to a temporary discontinuation and reduction of the drug. On the other hand, the formation of the patient's presacral pseudocyst may have been caused by several factors, including the use of Sulfatinib. Following complete surgical removal of the presacral tumor, the patient's anemia, poor nutritional status, the filling of the wound with haemostatic material and use of Sulfatinib contributed to delayed wound healing, resulting in a residual cystic cavity in the presacral area. Continued use of Sulfatinib further led to bleeding, allowing the cavity to expand and form a blood-encapsulated pseudocystic cavity. Given the complexities associated with poor incisional healing, as well as the formation of presacral effusion and haematoma following the removal of an anterior sacral mass[22; 23], we believe that the use of tyrosine kinase inhibitors should be carefully considered, as they have the potential to worsen these complications.
Local treatments, such as radiofrequency ablation, arterial embolization, and selective internal radiation therapy, are utilized to manage liver metastases by effectively reducing tumor burden and enhancing patients' quality of life[24; 25]. Although our patient received local treatment, there was no targeted drug intervention, resulting in the progression of the liver lesion. In addition, in some large NET centers, many patients with distant metastases have been effectively controlled with PPRT[25; 26; 27]. Several authors have reviewed case studies of presacral neuroendocrine tumors, and details can be found in the previous published reviews[24; 25]. We discuss here the possible complications following resection of presacral tumors in a focused manner. We strongly emphasize the importance of selecting a personalized protocol that is suitable for the patient's unique circumstances.