The treatment of end-stage HAE is complicated and can range from drug treatment to radical resection. Surgical therapy still remains the first-line treatment for end-stage HAE13,14. Brain metastasis is not a contraindication to surgery, and patients whose metastases were not located in important areas of the brain could still be treated with surgery. Previous treatments for HAE patients with IVC involvement include drug therapy, palliative treatment [PTCD, ERCP+ endoscopic retrograde biliary drainage (ERBD) and palliative surgery] and radical surgery13,15. In our study, all patients with HAE infringing on the IVC underwent liver resection combined with IVC resection, and this treatment has been reported in a few cases to be a safe and effective surgical scheme in end-stage HAE16. In comparison with IVC reconstruction after resection, the merits of resecting the IVC without reconstructing it are obvious and include a shorter operative time, less operative trauma, less anticoagulant drug use, and fewer complications17. Furthermore, compared with palliative resection, our approach resulted in no postoperative recurrence or residual lesions, which might indicate that radical resection can essentially be achieved by liver resection combined with IVC resection.
The studies investigating resection of the IVC are relatively rare. Unlike previously published case reports8, our case series includes patients with complex liver lesions. This series describing 13 patients who underwent IVC resection for HAE infringing on the IVC without prosthetic or autologous reconstruction is the largest to date. IVC involvement was previously an indication for palliative resection. Christian Partensky reported the cases of 18 patients who required liver resection for HAE. Of 9 patients who underwent palliative resection, 2 died during the follow-up period, indicating that IVC involvement does not have a survival advantage for HAE patients18. Unlike their results, our retrospective study of HAE infringing on the IVC, with a median follow-up duration of 18 months, showed that there was 1 case of operation-related mortality. Our team concluded that the cause of death was complex hepatectomy and that it had nothing to do with the absence of the IVC. These outcomes highlight the important opinion that patients undergoing IVC resection could achieve a radical cure and that less operative trauma could reduce the rate of surgery-related mortality.
Biliary leakage is a common complication of liver resection that led to persistent fever in 1 patient in our study (7.7%). The patient was cured after reducing the pressure in the biliary tract by endoscopic nasobiliary drainage (ENBD). Dziri et al.19 reported that omentoplasty could reduce the occurrence rate of postoperative biliary leakage after surgery for hepatic echinococcosis in a prospective, multi-centre, randomized trial. Ijichi et al.20 reported that the biliary leakage test was not an effective means of detecting biliary leakage in a randomized controlled study of 103 patients treated with hepatic resection. Our results show that bile leakage mainly occurred in the ex vivo resection group, which might be related to surgical trauma. Therefore, radical surgery should be performed as much as possible, and the surgeon should minimize unnecessary cutting of the liver surface area.
In patients with complete IVC blockage, the collateral circulation could provide sufficient venous return, and therefore, corresponding symptoms, such as lower limb and scrotal oedema, are uncommon. In this study, the IVC was completely blocked in 12 patients with HAE infringing on the IVC, and 4/5 of the inner diameter was violated in 1 patient. In our cases, preoperative IVC venography showed suitable compensation by the collateral circulation in all patients (Fig. 2). Hence, IVC reestablishment may not be feasible in these patients. In line with previous results21, no patients showed lower limb or scrotal oedema before the operation. However, in our study, 3 patients had lower limb and scrotal oedema after combined resection of the liver and RHIVC. All of these patients were in the ex vivo resection group. Therefore, it could not be determined whether the complication was related to the surgical trauma or the surgical approach. Further study is needed to elucidate whether it this complication is related to removal of the RHIVC. We believe that IVC reestablishment might be beneficial in patients who have poor compensation via the collateral circulation preoperatively.
Infection and thrombosis are the 2 major complications of IVC reconstruction, but both are uncommon. There may not be any clinical means of decreasing the incidence of graft thrombosis aside from short-term anticoagulation treatment22. In our study, all patients underwent IVC resection without reconstruction, and anticoagulation therapy was rarely used after surgery. The literature shows that the23 operation-related mortality rate of liver resection combined with IVC resection and artificial vascular graft reconstruction is 8.1%. To the best of our knowledge, there have been no studies strictly comparing the surgical outcomes of combined resection of the liver and the IVC with and without IVC reconstruction. Postoperative haemorrhage, including abdominal or gastrointestinal haemorrhage, is a common factor affecting mortality. From 1960 to 1972, the mortality rate was 70% and 94% after 5 and 10 years, respectively4. However, in our study, there was 1 case of operation-related mortality due to upper gastrointestinal haemorrhage (7.7%), which is a relatively low rate compared to those previously reported. It is possible that gastrointestinal bleeding might be a reason for portal venous system reconstruction because the patient was in the ex vivo resection group.
Renal dysfunction is another complication of performing IVC resection. It has been reported that21 patients with obstruction of the suprarenal IVC and a poor collateral circulation are at an increased risk of renal failure after IVC ligation. In our series, 1 patient had transient renal insufficiency after removal of the IVC and was cured with the corresponding treatment. The postoperative serum creatinine level was increased continuously for a short period of time in this patient who did not undergo IVC reconstruction. We believe that the reason for this outcome might be systemic postoperative infection. Hardwigsen et al.8 proposed that IVC reconstruction might be indispensable if haemodynamics are unstable intraoperatively or postoperatively. In our study, all patients underwent hepatectomy, and it was common to encounter unstable haemodynamics while blocking the hepatic portal system or during extracorporeal circulation. However, none of our patients developed operation-related renal failure. We also determined the Clavien–Dindo classification of the 13 patients; only 1 patient was classified as grade IIIa according to the postoperative therapy for patients with complicated hepatectomy because the patient needed ERCP and endoscopic nasobiliary drainage (ENBD) to reduce the biliary tract pressure, which might have been due to biliary reconstruction during autologous liver transplantation. Therefore, these complications were not the result of removal of the IVC.
This study was the first to explore the performance of IVC resection without reconstruction in treating end-stage hepatic alveolar echinococcosis. Furthermore, the preoperative preparation in these cases was performed well, the operations were difficult, and the surgical approach was unique. Additionally, this article indirectly reflects the shortcomings of previous reports and could serve as a reference for removal of the inferior vena cava. The extent of inferior vena cava invasion was used as an index for the surgical method. This method avoids residual lesions and could achieve radical resection to treat patients with multiple involved organs. The study also has some limitations. First, for studying this type of surgery, a larger sample size should be used. Second, this surgical method also lacks evidence from clinical prospective studies and multi-centre collaboration to verify the findings. Third, the study could not completely eliminate the effect of different types of hepatectomy.