Analysis of the efficacy of first hepatic portal blockade in laparoscopic microwave ablation treatment of hepatic vascular tumors

Abstract

BACKGROUND

In laparoscopic microwave ablation (MWA) of large hepatic hemangiomas with a maximum diameter between 5.0 cm and 10.0 cm, some scholars suggest that omitting occlusion of the first hepatic portal can simplify surgical procedures and shorten the operation time. Conversely, other scholars propose that occluding the first hepatic portal may reduce the “thermal sink effect”, enhance ablation efficiency, and lower the risk of adverse reactions. Currently, there is no consensus or relevant evidence regarding the necessity of occluding the first hepatic portal in such cases.

AIM

To compare the efficacy of laparoscopic MWA for large hepatic hemangiomas with vs without occlusion of the first hepatic portal, and to identify independent factors influencing the decision to perform occlusion.

METHODS

A retrospective analysis was conducted on 220 patients with large hepatic hemangiomas (5.0 cm ≤ maximum diameter < 10.0 cm) who underwent laparoscopic MWA performed by the same expert team. Based on whether the first hepatic portal was occluded during surgery, patients were divided into an occlusion group (n = 87) and a non-occlusion group (n = 133). After propensity score matching (PSM) at an approximate 1:1 ratio, the occlusion group (n = 87) and non-occlusion group (n = 79) were included. Baseline characteristics of both groups were compared before and after PSM. Multivariate logistic regression was used to analyze factors associated with the decision to perform portal occlusion. Outcome measures included Surgical-related indicators, postoperative incidence of adverse reactions, complete ablation rate, and postoperative hospital stay.

RESULTS

Tumor maximum diameter, number of hemangiomas, and distance from major hepatic vessels were identified as independent factors influencing the decision to perform portal occlusion. After PSM, the occlusion group showed significantly better outcomes than the non-occlusion group in terms of intraoperative ablation time, number of ablations, puncture site bleeding volume, conversion rate to open surgery, total bilirubin and indirect bilirubin levels on postoperative days 1 and 3, alanine aminotransferase level on postoperative day 3, and the incidence of hemolytic jaundice, hemoglobinuria, and acute kidney injury (all P < 0.05). The occlusion group also exhibited more favorable outcomes in operative time, alanine aminotransferase on postoperative day 1, aspartate aminotransferase level, incidence of pulmonary infection and pleural effusion, complete ablation rate, and postoperative hospital stay, although these differences were not statistically significant (P > 0.05).

CONCLUSION

Tumor maximum diameter, distance from major vessels, and number of tumors are independent factors influencing the decision to occlude the first hepatic portal during laparoscopic microwave ablation for large hepatic hemangiomas. Occlusion of the first hepatic portal during the procedure facilitates a high complete ablation rate, improves ablation efficiency, and reduces the incidence of postoperative adverse reactions.

Keywords: Large hepatic hemangioma; Microwave ablation; Blocking of the first hepatic portal vein; Propensity score; Laparoscopic surgery; Efficacy

Core Tip: Laparoscopic microwave ablation is safe and effective for small hemangiomas as it does not block the first hepatic portal. Giant hemangiomas (diameter ≥ 10.0 cm) are more commonly treated with hepatic resection rather than microwave ablation. If the first hepatic portal is not blocked, surgery is simpler and quicker for large hemangiomas (5.0 cm ≤ diameter < 10.0 cm). Conversely, blocking the first hepatic portal reduces the “heat sink effect” - a phenomenon where blood flow dissipates heat during ablation, thereby improving ablation efficiency and lowering the incidence of adverse reactions. However, there is no consensus or research on whether to block the first hepatic portal in this case.