Subsegmental approaches to S7: anatomic laparoscopic transdiaphragmatic and nonanatomic robotic transthoracic

Minimally invasive liver surgery of postero-superior segments (S4a, S7, S8) remains a challenge. The caudal view, an increased distance between trocars and the operative field, and the liver fulcrum limiting the view, contribute to the difficulty [1, 2]. We and other groups have previously reported the use of intercostal trocars to access subdiaphragmatic tumors (transdiaphragmatic approach) [3-5], only few reports on a laparoscopic total transthoracic approach, none (to our knowledge) dynamic manuscripts of a total transthoracic robotic approach, and none (to our knowledge) that use preoperative port site and anatomic modelling exist. Further, we developed a total transthoracic (thoracoscopic) approach to avoid a hostile abdomen, while bringing viewing axis and instruments close to the target [6-10]. In this context, this report details the advantages of a laparoscopic vs. robotic transthoracic approach. According to institutional protocol, reports of individual cases in print or video format do not require institutional review board approval.

A 68-year-old male on peritoneal dialysis with left colon adenocarcinoma and a single synchronous liver metastasis in S6-7 close to the root of the right hepatic vein underwent a laparoscopic transdiaphragmatic metastasectomy. Two years later, the patient developed a recurrent 1.5 cm liver metastasis in S7, which lend itself to a robotic transthoracic approach.

Following 3-D modelling and virtual port placement planning, the first metastasectomy was performed laparoscopically using a transdiaphragmatic approach. The recurrence was managed transthoracically due to more apical, subdiaphragmatic location. For this operation, a robotic approach was optimal as robotic wrist articulation facilitates manipulation via the limited intercostal space. This was particularly helpful during the diaphragmatic reconstruction.

Total transthoracic liver surgery is certainly an advanced procedure requiring superior MIS liver skills. Recommendations for starting with a total transthoracic approach are not unlike from starting a standard, none-transthoracic liver surgery. Early on in the experience we recommend advanced liver MIS skills, and single, small, subdiaphragmatic tumors away from major vessels. Nonetheless, when these recommendations are followed a total transthoracic approach may be safer and result in less access trauma, than traversing a hostile abdomen to reach the posterior-superior liver. Both laparoscopic and robotic transthoracic approaches can facilitate the resection of subdiaphragmatic tumors, especially in patients with hostile abdomens. While the laparoscopic approach has advantages due to a broader spectrum of available surgical tools (flexible tip camera, parenchymal dissection, and energy devices), the robotic wrist articulation facilitates manipulation via the restricted intercostal space.