Laparoscopic Caudal Approach of the Inferior Vena Cava for Isolated Segment 1 Liver Resection

Isolated laparoscopic resection of the hepatic caudate lobe (segment 1) is a very challenging procedure. Very few references are available on this technique, and the aim of this paper is to show the main technical aspects of laparoscopic caudal approach for segment 1. The subject was a 64-year-old woman with a past medical history of surgically treated breast cancer (pT1N0M0, with positive hormonal receptors). Adjuvant treatment was administered as well as radiotherapy and hormone therapy (tamoxifen). After 12 months of follow-up, an 18-mm single liver metastasis was detected in segment 1, suggestive of metastatic disease. A complementary study was conducted with magnetic resonance imaging, computed tomography and positron emission tomography, and no other lesions were identified. Isolated laparoscopic resection of segment 1 of the liver was performed with a caudal approach of the inferior vena cava. All the steps are extensively described. The surgery time was 120 min, and blood loss was less than 100 ml. No postoperative complications were registered. The patient was discharged on the third postoperative day. Isolated laparoscopic resection of the hepatic caudate lobe with a caudal approach of the inferior vena cava is a safe technique in selected patients and should be performed in centres with experience in liver surgery and advanced laparoscopy, because of its high complexity.


Introduction
The benefits of laparoscopic liver resection have been demonstrated over the past few years [1]. This technique was initially only performed for anterior liver segments but, with technical improvements, has been extended to more complex resections as well as posterior liver segments resections.
The aim of this paper is to show the main technical aspects of laparoscopic caudal approach for segment 1.

Case Report
The case of a 64-year-old woman with a past medical history of breast cancer previously operated (pT1N0M0, with positive hormonal receptors) is presented. Adjuvant treatment was administered with radiotherapy and hormone therapy (tamoxifen). After 11 months of follow-up, an 18-mm single liver metastasis was detected in segment 1, suggestive of metastatic disease. A complementary study was conducted with magnetic resonance imaging, computed tomography, and positron emission tomography, and no other lesions were identified. The patient was evaluated by a multidisciplinary team and proposed for liver resection.

Laparoscopic Technical Aspects
The patient was placed in the supine position, with anti-Trendelenburg and French position. A vacuum mattress was used to fix the patient to the surgical table. The surgeon was positioned between the patient's legs, the first assistant on the left side of the patient and the second assistant on her right. Trocars were positioned as follows: 12 mm supraumbilical (for the 30° camera), 12 mm on the right and left sides of the abdomen (both these trocars will be used by the main surgeon) and 5 mm subcostal right (first assistant trocar), subcostal left (cotton tape for Pringle manoeuvre is used in this trocar) and in the epigastrium (second assistant trocar for liver retraction).
An exploratory laparoscopy was carried out, showing no other findings in the abdomen cavity. A laparoscopic liver ultrasound was performed intraoperatively, and a single segment 1 liver lesion was confirmed.
As shown in the video, the first step was to section the round ligament and the left triangular ligament, to allow moving the left hepatic lobe to the right side of the patient. The left paracaval edge of segment 1 was initially approached. Subsequently, a caudal approach of the inferior vena cava was used (Fig. 1), separating it from segment 1 of the liver, using a sealant instrument (LigaSure™) to ligate the inferior vena cava branches. The Pringle manoeuvre was applied with an ischemic preconditioning (10 min of liver ischemia followed by 10 min of liver perfusion), then a continued extracorporeal Pringle manoeuvre was used; the liver parenchyma transection was performed with an ultrasonic dissector, the bipolar sealer with monopolar coagulation. The segment 1 portal branch was sectioned with and Endo GIA™ (Fig. 2). The specimen was removed from the abdomen with a protector bag through a 3-cm supraumbilical skin incision. The surgery time was 120 min, and the blood loss was less than 100 ml. The postoperative course was excellent, without any complication, and the patient was discharged on the third postoperative day. The definitive histopathological analysis showed a hepatocellular adenoma associated to alpha-1 (FHN) mutation. The liver margins were disease-free.

Discussion
The first cases of segment 1 laparoscopic liver resection were published in 2006 [2], showing that localisation of liver metastases is not a limitation for a laparoscopic approach.
Depending on the site and number of metastases, segment 1 of the liver can be approached from different sides [4]: the left side of segment 1, which is the most common approach in laparoscopic liver resection because there are more technical advantages [5]; the posterior right approach, which is more often used in large tumours located on the right side of segment 1; and finally, a completely posterior approach, which is seldom used because of its difficulty.
In this case, a combined approach was chosen: left and caudal because the laparoscopic approach gives a better vision of the anterior wall of the inferior vena cava and makes it easy to mobilise segment 1.
Although segment 1 surgery is a minor liver resection, an ischemic preconditioning was performed. This manoeuvre allows us to perform a continuous liver transection and avoid intermittent clamping, which in our opinion, would be more time-consuming. Apart from inflow control, in this type of surgery (as in all liver surgeries), low central venous pressure should be maintained to avoid bleeding from the liver parenchyma and to facilitate dissection of inferior vena cava.
In this clinical case, liver metastasis from breast cancer was suspected, although pathological examination finally showed a hepatocellular adenoma. All preoperative tests showed findings which correlated with metastatic disease, and adenoma was not radiologically suspected. A multidisciplinary meeting was held, and because of the difficulty of liver biopsy, the panel agreed on surgical excision, due to the potential benefits on survival in selected cases of resected liver metastasis of breast cancer [10].
Finally, in our opinion, laparoscopic resection of segment 1 of the liver with a caudal approach of the inferior vena cava is a safe technique in selected patients and should be performed in centres experienced in liver surgery and advanced laparoscopy because of the considerable complexity of this technique.