Laparoscopic posterior segmental resections: How I do it: Tips and pitfalls.

Laparoscopic liver resections of lesions in the postero-superior segments (Sg 4a, 7, 8) can be technically challenging. A profound experience in open and laparoscopic surgery is essential to ensure success without compromising surgical safety and oncologic efficiency when applying the laparoscopic approach for these segments. While many experienced surgeons have initially called the postero-superior segments the non-laparoscopic segments, this dogma has been challenged by different groups reporting good results in terms of safety and feasibility for parenchymal-sparing non-anatomical and, however less so, for anatomical resections (AR). Parenchymal-sparing liver resection is nowadays the gold standard for the treatment of colorectal liver metastases where repeated resections have demonstrated to improve patient's cancer related short and long-term outcome. This can be achieved by performing anatomical or non-anatomical segmental resections. Different surgical techniques to facilitate such resections have been described. The diamond technique has specifically been developed for the non-anatomical resection of non-peripheral lesions in the postero-superior segments and reported to be feasible, reproducible and moreover, oncologic efficient. Similarly, techniques for AR have been described acknowledging that in the minimally invasive setting such resections are technically more demanding requiring precise preoperative planning and a standardized surgical technique to allow pursuing oncological quality of the parenchyma sparing principle. We herein discuss technique, results and tips and tricks of applying the diamond technique for non-anatomical liver resection as well as the practice for AR of lesions in the postero-superior segments.