Strategies in liver surgery

Abstract

Partial liver resection is major surgery with an associated morbidity rate in our study group of 23% and a mortality rate of 5.8%. The most important risk factor for developing postoperative complications is blood loss and consequently, the administration of packed red blood cells. Most of the blood loss occurs during the transection phase. New precoagulation devices significantly decrease the blood loss during transection of the liver without applying the Pringle maneuver, when compared to ultrasonic dissection.

In the Netherlands the most important indication for partial liver resection is the presence of colorectal metastases. During surgery intraoperative ultrasound (IOUS) is performed to identify and localize the colorectal metastases and their relation with major vascular and biliar structures. In spite of the high specificity of IOUS, the recurrence rate after partial liver resection is substantial, implying that small metastases remain undetected using IOUS. In our series the addition of contrast did not significantly improve the diagnostic accuracy of IOUS, mainly as a result of the adequacy of IOUS. In a selected population partial liver resection is the sole potentially curative treatment and is associated with a 5-year survival rate of 38%. However, only 20-25% of patients with colorectal liver metastases are eligible for partial liver resection.

In selected patients unresectable metastases can be treated with radiofrequency ablation (RFA). With this method a high-frequency alternating current is applied through a needle electrode inserted directly into the tumor. This alternating current induces hyperthermia, resulting in coagulative necrosis. Introduction of RFA in the Netherlands has been accompanied by unacceptably high recurrence rates. Patients must be selected very carefully. Currently, the most promising local recurrence rates have been reported for small tumors (< 3cm) treated by laparoscopy or laparotomy. Moreover, an evident learning curve has been described for this technique, which can be overcome by concentrating patients in specialized centers.

A strategy to extend the number of patients treated surgically is the combination of partial liver resection and local ablation. The aim of this strategy is to resect the bulk of disease or larger tumors followed by local ablation of any residual unresectable liver tumor, while preserving adequate hepatic reserve. This combination is remarkable, since local ablation, in contrast to partial liver resection, should still be considered a palliative intervention. Consequently, partial liver resection with its associated morbidity is performed in a palliative setting. The initial results of this strategy in the Netherlands show that the postoperative morbidity and mortality are similar to those reported after partial liver resection alone. Partial liver resection for benign disease is an effective procedure to relieve invalidating abdominal symptoms. Since partial liver resection is associated with substantial morbidity and even mortality it should be considered only in patients with severe or progressive symptoms and, because of the risk of spontaneous rupture or malignant degeneration, in patients with a large hepatocellular adenoma (>5cm).