Comparison between the difficulty of laparoscopic limited liver resections of tumors located in segment 7 versus segment 8: An international multicenter propensity‐score matched study

Abstract

Background Presently, according to different difficulty scoring systems, there is no difference in complexity estimation of laparoscopic liver resection (LLR) of segments 7 and 8. However, there is no published data supporting this assumption. To date, no studies have compared the outcomes of laparoscopic parenchyma‐sparing resection of the liver segments 7 and 8. Methods A post hoc analysis of patients undergoing LLR of segments 7 and 8 in 46 centers between 2004 and 2020 was performed. 1:1 Propensity score matching (PSM) was used to compare isolated LLR of segments 7 and 8. Subset analyses were also performed to compare atypical resections and segmentectomies of 7 and 8. Results A total of 2411 patients were identified, and 1691 patients met the inclusion criteria. Comparison after PSM between the entire cohort of segment 7 and segment 8 resections revealed inferior results for segment 7 resection in terms of increased blood loss, blood transfusions, and conversions to open surgery. Subset analyses of only atypical resections similarly demonstrated poorer outcomes for segment 7 in terms of increased blood loss, operation time, blood transfusions, and conversions to open surgery. Conversely, a subgroup analysis of segmentectomies after PSM found better outcomes for segment 7 in terms of a shorter operation time and hospital stay. Conclusion Differences in the outcomes of segments 7 and 8 resections suggest a greater difficulty of laparoscopic atypical resection of segment 7 compared to segment 8, and greater difficulty of segmentectomy 8 compared to segmentectomy 7.

Minimally invasive transthoracic resection of a segment eight liver tumor

“…An anterior fissure vein (AFV) runs between the ventral and dorsal subsegments and may drain into either the RHV or the MHV. A dominant AFV is found in up to 45% of patients and may be a helpful landmark when performing an anatomical subsegmentectomy [37,38] .…”

“…Furthermore, the increased distance between the laparoscope, the operative trocars and the resection area, together with the straight structure of most laparoscopic instruments, lead to poor surgical visualization of the surgical field and the difficulty in developing a transection plane. This impacts the control of bleeding and the identification of surgical margins [20,38] . While some technological innovations, such as a flexible tip camera, are helping to overcome the fulcrum, S8 remains a challenging segment to access.…”

“…Another approach uses IOUS to identify the right anterior pedicle, followed by transection of a small bridge of parenchyma on the ventral liver surface to identify P8 (transparenchymal approach). Early P8 clamping is useful for allowing demarcation of the right-sided resection margin, which is to the left of the RHV [33,37,38] . Alternatively, a dye or indocyanine green can be injected directly into P8 to stain the segment.…”

“…To maintain the correct transection plane on the right side, it is necessary to proceed again from the cranial side, exposing the RHV at its confluence and continuing to the periphery. S8 resection is completed by separating the remaining parenchyma from the IVC [33,37,38] .…”

Open Parenchymal Sparing Posterosuperior Liver Tumor Resection for Colorectal Liver Metastasis With Proximity to Hepatic Veins

“…Open parenchymal-sparing liver resection is a viable option for tumors located in difficult segments such as in posterosuperior or caudate lobe. 3,4 Difficulty in gaining access with minimally invasive approach utilizing a caudocranial view does not apply in the open method by utilizing an anterior view with the liver lobe fully mobilized. This way, an optimal parenchymal preservation can be achieved without any fear of inducing postoperative hepatic insufficiency.…”