Surgical Indications and Procedures for Resection of Hepatic Malignancies Confined to Segment VII

Comparative Analysis of the Safety and Feasibility of Laparoscopic Versus Open Segment 7 Hepatectomy

BACKGROUND

Laparoscopic hepatectomy has been widely accepted owing to its advantages as a minimally invasive surgery; however, laparoscopic segment 7 (S7) hepatectomy (LSH) has been rarely reported. We aimed to explore the safety and feasibility of LSH by comparing it with open surgical approaches.

METHODS

Twenty-nine patients who underwent S7 hepatectomy between January 2016 and January 2023 were enrolled in this study. The patients' characteristics, intraoperative details, and postoperative outcomes were compared between the 2 groups.

RESULTS

No significant differences were observed in the preoperative data. The patients who underwent LSH had significantly shorter hospital stays ( P =0.016) but longer operative times ( P =0.034) than those who underwent open S7 hepatectomy. No significant differences in blood loss ( P =0.614), transfusion ( P =0.316), hospital expenses ( P =0.391), surgical margin ( P =0.442), rate of other complications, postoperative white blood cell count, and alanine aminotransferase and aspartate aminotransferase levels were noted between the 2 groups ( P >0.05). For hepatocellular carcinoma, the results showed no differences in either disease-free survival ( P =0.432) or overall survival ( P =0.923) between the 2 groups.

CONCLUSIONS

LSH is a safe and feasible surgical procedure that is efficient from an oncological point of view. It may be the preferred technique for lesions in the S7 of the liver.

Robotic anatomical resection for hepatocellular carcinoma located within segment 7 using the Glissonean approach

Worldwide use of robotic-assisted hepatectomy has increased dramatically over the past two decades. The role of robotic liver surgery is still controversial, especially with respect to its long-term oncological outcomes in treating early-stage hepatocellular carcinoma (HCC). The Glissonean approach is a fundamental technique for anatomical resection using open and laparoscopic liver surgery. To our knowledge, there have been few reports on purely robotic anatomical segmentectomy 7 for HCC using the Glissonean approach have been described. The present study describes the technical details and surgical outcomes of totally robotic segmentectomy 7 using the Glissonean approach. Fourteen patients with HCC limited to segment 7 underwent segmentectomy 7 from January 2019 through April 2023 in our hospital. The surgical techniques, peri-operative, and oncological outcomes were analyzed. Purely robotic anatomical segmentectomy 7 using the Glissonean approach was safe and feasible with the technology described herein in all of the 14 patients. The peri-operative and oncological outcomes were better and/or comparable with those of other similar hepatic resections using open approach and/or laparoscopic approach. The median follow-up time was 18 months. Intrahepatic recurrence occurred in 2 (14.3%) patient within one year following surgery. The 3-year overall survival rate was 81%. Although technically challenging, the purely robotic segmentectomy 7 could be performed safely and simultaneously with oncological radicality using the Glissonean approach.

Laparoscopic and open minor liver resection for hepatocellular carcinoma with clinically significant portal hypertension: a multicenter study using inverse probability weighting approach

BACKGROUND

Liver resection offers substantial advantages over open liver resection (OLR) for patients with hepatocellular carcinoma (HCC) in terms of reduced intraoperative blood loss and morbidity. However, there is limited evidence comparing the indications and perioperative outcomes with the open versus laparoscopic approach for resection. This study aimed to compare postoperative outcomes between patients undergoing laparoscopic liver resection (LLR) and OLR for HCC with clinically significant portal hypertension (CSPH).

METHODS

A total of 316 HCC patients with CSPH (the presence of gastroesophageal varices or platelet count < 100,000/ml and spleen diameter > 12 cm) undergoing minor liver resection at eight centers were included in this study. To adjust for confounding factors between the LLR and OLR groups, an inverse probability weighting method analysis was performed.

RESULTS

Overall, 193 patients underwent LLR and 123 underwent OLR. After weighting, LLR was associated with a lower volume of intraoperative blood loss and the incidence of postoperative complications (including pulmonary complications, incisional surgical site infection, and paralytic ileus) compared to the OLR group. The 3-, 5-, and 7-year postoperative recurrence-free survival rates were 39%, 26%, and 22% in the LLR group and 49%, 18%, and 18% in the OLR group, respectively (p = 0.18). And, the 3-, 5-, and 7-year postoperative overall survival rates were 71%, 56%, and 44% in the LLR group and 76%, 51%, 44% in the OLR group, respectively (p = 0.87).

CONCLUSIONS

LLR for HCC patients with CSPH is clinically advantageous by lowering the volume of intraoperative blood loss and incidence of postoperative complications, thereby offering feasible long-term survival.

Pure abdominal laparoscopic approach versus thoraco-abdominal laparoscopic approach: What is the best technique for liver resection in segment 7 and segment 8? An answer from the Institut Mutualiste Montsouris experience with short- and long-term outcome evaluation

BACKGROUND

Lesions in segments 7 and 8 are a challenge during standard laparoscopic liver resection. The addition of transthoracic trocars could be useful in the standard abdominal approach for laparoscopic liver resection. We report our experience with a thoraco-abdominal laparoscopic combined approach for liver resection with the aim of comparing short- and long-term outcomes.

METHODS

We reviewed 1,003 laparoscopic liver resections in a prospectively maintained, single-institution database. We compared patient outcomes intraoperatively and postoperatively. We analyzed the long-term outcomes of the colorectal liver metastasis subgroup. Propensity score matching 1:1 was performed based on the following variables: age, American Society of Anesthesiologists, body mass index, previous abdominal surgery, multiple or single liver resection, lesion >50 mm or <50 mm, presence of solitary or multiple lesions, T stage, and N stage.

RESULTS

The standard abdominal approach was used in 110 laparoscopic liver resections, and the thoraco-abdominal laparoscopic combined approach was used in 62 laparoscopic liver resections. The thoraco-abdominal laparoscopic combined approach was associated with better intraoperative results (less blood loss and no need for conversion to open surgery). The R1s rate for segmentectomy 7 and 8 was lower in the thoraco-abdominal laparoscopic combined approach in the entire group and in the colorectal liver metastasis subgroup. In the colorectal liver metastasis subgroup, the 3- and 5-year overall survival was 90% and 80% in the thoraco-abdominal laparoscopic combined approach group and 76% and 52% in the standard abdominal approach group, respectively (P = .02). In univariate and multivariate analysis, the thoraco-abdominal laparoscopic combined approach was a significant factor that positively affected disease-free survival and overall survival.

CONCLUSION

The thoraco-abdominal laparoscopic combined approach in laparoscopic liver resection in segments 7 and 8 is safe and feasible, and it has demonstrated better oncologic outcomes than the pure abdominal approach, especially in segmentectomy.

Treatment of hepatic venous system hemorrhage and carbon dioxide gas embolization during laparoscopic hepatectomy via hepatic vein approach

With the improvement of laparoscopic surgery, the feasibility and safety of laparoscopic hepatectomy have been affirmed, but intraoperative hepatic venous system hemorrhage and carbon dioxide gas embolism are the difficulties in laparoscopic hepatectomy. The incidence of preoperative hemorrhage and carbon dioxide gas embolism could be reduced through preoperative imaging evaluation, reasonable liver blood flow blocking method, appropriate liver-breaking device, controlled low-center venous pressure technology, and fine-precision precision operation. In the case of blood vessel rupture bleeding in the liver vein system, after controlling and reducing bleeding, confirm the type and severity of vascular damage in the liver and venous system, take appropriate measures to stop the bleeding quickly and effectively, and, if necessary, transfer the abdominal treatment in time. In addition, to strengthen the understanding, prevention and emergency treatment of severe CO2 gas embolism in laparoscopic hepatectomy is also the key to the success of surgery. This study aims to investigate the methods to deal with hepatic venous system hemorrhage and carbon dioxide gas embolization based on author's institutional experience and relevant literature. We retrospectively analyzed the data of 60 patients who received laparoscopic anatomical hepatectomy of hepatic vein approach for HCC. For patients with intraoperative complications, corresponding treatments were given to cope with different complications. After the operation, combined with clinical experience and literature, we summarized and discussed the good treatment methods in the face of such situations so that minimize the harm to patients as much as possible.

Suitability of Laparoscopic Liver Resection of Segment VII: a Retrospective Two-Center Study

BACKGROUND

Resecting liver tumors located in Couinaud's segment VII is challenging; the efficacy and safety of laparoscopic liver resection for segment VII lesions compared to open liver resection remain unclear.

METHODS

Medical records of 84 patients who underwent liver resection of segment VII at Kobe University Hospital and Hyogo Cancer Center between 2010 and 2021 were retrospectively analyzed. Surgical outcomes were compared between laparoscopic liver resection and open liver resection groups using propensity matching analysis.

RESULTS

Thirty-one and 53 patients underwent laparoscopic liver resection and open liver resection, respectively. After propensity matching, 29 patients were included in each group. The laparoscopic liver resection group had a significantly longer operation time (407 vs. 305 min, P = 0.002), lower blood loss (100 vs. 230 mL, P = 0.004), and higher postoperative alanine aminotransferase levels (436 vs. 252 IU/L, P = 0.008) than the open liver resection group. In patients with liver cirrhosis, the proportion of patients with postoperative liver-specific complications was higher in the laparoscopic liver resection group than in the open liver resection group (57% vs 11%, P = 0.049), although there was no significant difference in postoperative liver-specific complication rates between the groups in patients without liver cirrhosis.

CONCLUSIONS

For liver resection of segment VII, laparoscopic liver resection led to higher postoperative liver damage than open liver resection. Open liver resection may be better for patients with liver cirrhosis to avoid postoperative liver-specific complications. Laparoscopic liver resection could be an acceptable procedure for patients without liver cirrhosis, with some merits such as less blood loss.

Laparoscopic versus open resections in the posterosuperior liver segments within an enhanced recovery programme (ORANGE Segments): study protocol for a multicentre randomised controlled trial

BACKGROUND

A shift towards parenchymal-sparing liver resections in open and laparoscopic surgery emerged in the last few years. Laparoscopic liver resection is technically feasible and safe, and consensus guidelines acknowledge the laparoscopic approach in the posterosuperior segments. Lesions situated in these segments are considered the most challenging for the laparoscopic approach. The aim of this trial is to compare the postoperative time to functional recovery, complications, oncological safety, quality of life, survival and costs after laparoscopic versus open parenchymal-sparing liver resections in the posterosuperior liver segments within an enhanced recovery setting.

METHODS

The ORANGE Segments trial is an international multicentre randomised controlled superiority trial conducted in centres experienced in laparoscopic liver resection. Eligible patients for minor resections in the posterosuperior segments will be randomised in a 1:1 ratio to undergo laparoscopic or open resections in an enhanced recovery setting. Patients and ward personnel are blinded to the treatment allocation until postoperative day 4 using a large abdominal dressing. The primary endpoint is time to functional recovery. Secondary endpoints include intraoperative outcomes, length of stay, resection margin, postoperative complications, 90-day mortality, time to adjuvant chemotherapy initiation, quality of life and overall survival. Laparoscopic liver surgery of the posterosuperior segments is hypothesised to reduce time to functional recovery by 2 days in comparison with open surgery. With a power of 80% and alpha of 0.04 to adjust for interim analysis halfway the trial, a total of 250 patients are required to be randomised.

DISCUSSION

The ORANGE Segments trial is the first multicentre international randomised controlled study to compare short- and long-term surgical and oncological outcomes of laparoscopic and open resections in the posterosuperior segments within an enhanced recovery programme.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03270917 . Registered on September 1, 2017. Before start of inclusion.

PROTOCOL VERSION

version 12, May 9, 2017.

Impact of laparoscopic parenchyma-sparing resection of lesions in the right posterosuperior liver segments on surgical outcomes: A multicenter study based on propensity score analysis

BACKGROUND

Laparoscopic liver resection for hepatic lesions is increasingly performed worldwide. However, parenchyma-sparing laparoscopic liver resection for hepatic lesions in the right posterosuperior segments is very technically demanding. This study aimed to compare postoperative outcomes between patients undergoing laparoscopic liver resection and open liver resection for hepatic lesions in the right posterosuperior segments.

METHODS

In total, 617 patients who underwent liver resection of hepatic lesions in the right posterosuperior segments (segment Ⅶ or Ⅷ) at 8 centers were included in this study. We lessened the impact of confounders through propensity score matching, inverse probability weighting, and double/debiased machine learning estimations.

RESULTS

After matching and weighting, the imbalance between the 2 groups significantly decreased. Compared with open liver resection, laparoscopic liver resection was associated with a lower volume of intraoperative blood loss and incidence of postoperative complications in the matched and weighted cohorts. After surgery, the incidence of pulmonary complication and cardiac disease was lower in the laparoscopic liver resection group than in the open liver resection group in both the matched and weighted cohorts. The odds ratios of laparoscopic liver resection for postoperative complications in the matched and weighted cohorts were 0.49 (95% confidence interval, 0.29-0.83) and 0.40 (95% confidence interval, 0.25%-0.64%), respectively. The double/debiased machine learning risk difference estimator for postoperative complications of laparoscopic liver resection was -19.8% (95% confidence interval, -26.8% to -13.4%).

CONCLUSION

Parenchyma-sparing laparoscopic liver resection for hepatic lesions in the right posterosuperior segments had clinical benefits, including lower volume of intraoperative blood loss and incidence of postoperative complications.

Laparoscopic anatomic liver resection of segment 7 using a caudo-dorsal approach to the right hepatic vein

BACKGROUND

Laparoscopic anatomic liver resection of segment 7 (S7) is technically challenging because of the posterosuperior location and the lack of clear anatomical landmarks [1-4]. Here, we introduce a caudo-dorsal approach, which may offer a benefit for the difficult procedure.

METHODS

The patient was a 53-year-old man with hepatocellular carcinoma located in S7 of the liver. After the transection of caudate process, the Glissonean pedicle of S7 (G7) extending from the right posterior Glissonean pedicle was identified on the liver dorsal side. The demarcation line was noted by isolating and clamping G7. The intraoperative ultrasound was then used to assess the extent of the tumor. The right hepatic vein was approached from the dorsal side and continuously exposed in a caudal-cranial direction along the anterior surface of inferior vena cava after isolating and cutting the venous branches draining S7. Following the dissection of G7, the liver parenchymal transection was proceeded along the ischemic line between segment 6 and 7 with the ventral cutting plane extended to join the dorsal one. The liver parenchyma of the ventral side of the exposed right hepatic vein (RHV) was further transected from the dorsal side toward the root side of RHV. The resection of S7 was completed with perihepatic ligaments dissection.

RESULTS

The intermittent Pringle maneuver (15 min occlusion and 5 min reperfusion) was applied when necessary with a total time of 45 min. The operation time was 200 min, the estimated blood loss was 300 ml, and no transfusion was required. Pathology confirmed moderately differentiated HCC with negative surgical margin. The patient was discharged on postoperative day 8 with no complications and has been followed up for 8 months without recurrence.

CONCLUSION

This caudo-dorsal approach for laparoscopic anatomical S7 segmentectomy is easy and feasible when performed by experienced surgeons at experienced centers in well-selected patients.

Impact of Abdominal Incision Type on Postoperative Pain and Quality of Life Following Hepatectomy

BACKGROUND

The aim of this prospective study was to analyze the impact of abdominal incision type on postoperative pain and quality of life (QOL) in hepatectomy.

METHODS

In patients undergoing hepatectomy by open, hybrid, or pure laparoscopic approaches, we classified abdominal incisions as: pure laparoscopic (LAP), midline (MID), J-shaped (J), and J-shaped incision plus thoracotomy (TRC). Postoperative pain was measured on postoperative day (POD) 3, 7, 30, and 90 using a visual analog scale (VAS). QOL was evaluated using the short-form-36 questionnaire preoperatively and on POD 30 and 90.

RESULTS

We categorized 165 patients into LAP (n = 9, 5%), MID (n = 21, 13%), J (n = 95, 58%), and TRC (n = 40, 24%) groups. Median VAS scores on PODs 3/7/30/90 were: LAP, 27.5/7.5/10/10; MID, 30/10/15/5; J, 50/27.5/20/10, and TRC, 50/30/30/19. The J and TRC groups had significantly higher VAS scores vs. MID on PODs 3 and 7; the LAP and MID groups did not differ significantly. No significant positive correlations were observed between incision length and postoperative VAS, when we stratified patients into two groups according to the presence or absence of a transverse incision. Physical QOL summary scores did not return to preoperative levels even on POD 90, in patients with an additional transverse incision. Mental QOL summary scores worsened with postoperative complications rather than with abdominal incision type.

CONCLUSIONS

Transverse incisions, rather than incision length, led to worse midline incision pain and poorer QOL recovery post-hepatectomy. A hybrid approach may be a considerable option when pure laparoscopic hepatectomy is technically difficult.

TRIAL REGISTRATION

This study was registered in the UMIN Clinical Trials Registry (registration number: UMIN000017467; http://www.umin.ac.jp/ctr/index.htm ).

Robotic Liver Surgery - Current Standards and Future Perspectives

BACKGROUND

 Robotic liver surgery is emerging as the future of minimal invasive surgery. The robotic surgical system offers a stable camera platform, elimination of physiologic tremor, augmented surgical dexterity as well as improved ergonomics because of a seated operating position. Due to the theoretical advantages of the robotic assisted system, complex liver surgery might be an especially interesting indication for a robotic approach since it demands delicate tissue dissection, precise intracorporeal suturing as well as difficult parenchymal transection with subsequent need for meticulous hemostasis and biliostasis.

MATERIAL AND METHODS

 An analysis of English and German literature on open, laparoscopic and robotic liver surgery was performed and this review provides a general overview of the existing literature along with current standards and aims to specifically point out future directions of robotic liver surgery.

RESULTS

 Robotic liver surgery is safe and feasible compared to open and laparoscopic surgery, with improved short-term postoperative outcomes and at least non-inferior oncological outcomes.

CONCLUSION

 In complex cases including major hepatectomies, extended hepatectomies with biliary reconstruction and difficult segmentectomies of the posterior-superior segments, robotic surgery appears to emerge as a reasonable alternative to open surgery rather than being an alternative to laparoscopic procedures.

Optimal indications for an intercostal port for the superior segments in laparoscopic partial liver resection

INTRODUCTION

Intercostal port is useful for the superior segments in laparoscopic liver resection, but optimal indications for its use remain unclear. This study analyzed the surgical outcomes in patients undergoing laparoscopic partial liver resection for superior segments to determine the optimal indications.

METHODS

A total of 30 cases of laparoscopic partial liver resection for superior segments were retrospectively reviewed. First, comparison of cases according to use of the intercostal port was performed. Second, cases were classified into two groups according to the branch of the hepatic vein in the superior segments: superior-ventral group (S4a/S8vent: Svent group, n = 18) and superior-dorsal group (S7/S8dor: Sdor group: n = 12). The surgical outcomes were then compared to assess the performance of intercostal ports.

RESULTS

No differences in surgical outcomes were observed between patients with or without intercostal port. In this series, no complication due to the intercostal port, and no major complication were observed. In the comparison between Svent and Sdor, similar values of the operation time (Svent: 275 minutes vs Sdor: 316 minutes, P = .161) and blood loss (Svent: 30 mL vs Sdor: 17 mL, P = .718) were observed in both groups. The tumor size tended to be smaller in Sdor (Svent: 20 mm vs Sdor: 17 mm, P = .018), but use of the intercostal port was significantly more frequent in Sdor (58%) compared to Svent (33%) (P < .001).

CONCLUSION

The lesion located at Sdor or that close to this location was considered as optimal indication for placement of intercostal port in patients undergoing laparoscopic partial liver resection.

Totally laparoscopic anatomic S7 segmentectomy using in situ split along the right intersectoral and intersegmental planes

BACKGROUND

The traditional open or laparoscopic segmentectomy of liver segment 7 (S7) requires exposing and controlling the root of the right hepatic vein(RHV)after full mobilization and lifting up of the right liver before liver transection. This approach violates the "no-touch" principle for malignant tumors, and makes laparoscopic resection technically challenging. So reports on isolated totally laparoscopic anatomic S7 segmentectomy have rarely been reported. This study describes our experience in laparoscopic anatomic S7 segmentectomy using in situ split along the right intersectoral and intersegmental planes of the liver. To our knowledge, this is the first description of this novel approach.

METHODS

From September 2017 to May 2019, patients who underwent laparoscopic anatomic S7 segmentectomy for hepatocellular carcinoma at the HPB Surgery Department, Sun Yat-Sen Memorial Hospital entered into this retrospective study. This in situ split approach was designed using main vessels as the plane markers of right intersectoral and intersegmental planes, along which liver transection was carried out. There was no need to mobilize the right liver and control the root of RHV.

RESULTS

There were 9 women and 15 men. The average diameter of the tumors on preoperative CT/MR was 3.4 cm (range 2-6 cm). All the procedures were successfully carried out laparoscopically. There was no perioperative death. The average operative time was 216.5 min (range 180-310 min). The average blood loss was 320 ml (range 120-620 ml). Pathological study showed all the operations to be R0 resections.

CONCLUSION

Laparoscopic anatomic S7 segmentectomy using the in situ split approach resulted in R0 liver resection in all our patients with primary liver cancer. The operation was technically feasible and it provided a better view and increased maneuverability in the cramped operative space compared with the traditional open/laparoscopic approach. The approach also better complies with the "no-touch" principle for malignant tumors. Its long-term oncological outcomes require further studies.

Laparoscopic Versus Open Liver Resection for Difficult Lesions: A Meta-Analysis

Background: The value of laparoscopic liver resection (LLR) for difficult lesions (located in segments I, IVa, VII, and VIII) is still controversial nowadays. The aim of this study was to summarize quantitatively the evidence related to this issue. Materials and Methods: Two investigators independently searched the Medline, Embase, Science Citation Index Expanded, and Cochrane Library databases for eligible studies published before December 2017. The RevMan 5.3 software was utilized for statistical meta-analysis. Weighted mean differences (WMDs) and odds ratios (ORs) were calculated for continuous and dichotomous variables, respectively. Results: Five studies with a total number of 638 patients were included in the present meta-analysis, with 274 patients in the LLR group and 364 in the open liver resection (OLR) group. The LLR did not increase the operative time (WMD 12.42 minutes; 95% confidence interval [CI] -8.54 to 33.38 minutes; P = .25) or blood transfusion requirement (OR 0.81; 95% CI 0.40-1.64; P = .57) compared with OLR. Conversely, LLR was associated with significantly lower intraoperative blood loss (WMD -140.57 mL; 95% CI -203.39 to -77.76 mL; P < .001), shorter hospital stay (WMD -2.88 days; 95% CI -4.84 to -0.92 days; P = .004), and lower overall morbidity (OR 0.43; 95% CI 0.28-0.65; P < .001). The oncologic outcomes of R0 resection rate, surgical margin, and tumor recurrence were comparable in the two groups. Conclusion: LLR for difficult lesions in selected patients is safe, technically feasible, and advantageous when performed by experienced surgeons.

Surgical Approach to "Right Hepatic Core": Deepest Region Surrounded by Major Portal Pedicles and Right Hepatic Vein

BACKGROUND/AIMS

The resection of hepatic tumors located in the region surrounded by the right hepatic vein (RHV) and the portal pedicles of the right paramedian/lateral sector (the right hepatic core) remains a challenge for liver surgeons. The aim of this study was to demonstrate the surgical techniques and outcomes of our atypical-parenchyma-sparing hepatectomy (atypical-PSH) approach for the removal of tumors in the right hepatic core.

METHODS

Perioperative records of 1,179 consecutive patients who had undergone hepatectomy for hepatocellular carcinoma or colorectal liver metastases from January 2006 to December 2014 were retrospectively reviewed.

RESULTS

Twenty-six patients (2%) had a tumor in the right hepatic core. Among them, 20 patients underwent atypical-PSH, including the anterior approach (resection of the right paramedian hepatic parenchyma, n = 9), posterior approach (resection of the right lateral hepatic parenchyma, n = 10), and transhepatic approach (tumor enucleation from the raw surfaces along the RHV, n = 1). Their postoperative outcomes were similar to the remaining 6 patients who had undergone right hepatectomy.

CONCLUSIONS

Atypical-PSH can be safely applied for the removal of tumors in the right hepatic core. This technique may have potential advantages in preserving hepatic function for postoperative chemotherapy and repeated hepatectomy for future recurrence.

Systematic review of the feasibility and future of laparoscopic liver resection for difficult lesions

Laparoscopic liver resection (LLR) is now performed widely, but is difficult to accomplish in some anatomical locations, such as the posterosuperior segments (S7 and S8) and caudate lobe (S1). An international survey revealed that lesions in these locations are less frequently indicated for LLR than those in other segments. Recent reports from experienced centers document several case series and present technical tips for treating such lesions. The lateral approach using intercostal (transdiaphragmatic) trocars was reported to be useful for lesions in the posterosuperior segments with a semi- to full-decubitus position. The thoracoscopic approach was also reported to be useful for lesions just under the diaphragm dome, but the tumor location and patient selection should be considered carefully because pneumoperitoneum pressure and Pringle's maneuver cannot be applied. Several case series have described the feasibility of LLR for caudate lobe lesions, with similar operative outcomes to lesions in the posterosuperior segments, but this demands technical expertise. The caudal view of laparoscopy is advantageous for approaching the caudate lobe. We conducted a systematic review to clarify the feasibility of LLR for difficult lesions and discuss its current and future status.

Human liver territories: Think beyond the 8-segments scheme

Worldwide, compartmentalization of the human liver into portal venous territories today follows the eight-segments scheme credited to Couinaud. However, there are increasing reports of anatomical, radiological and surgical observations that contradict this concept. This paper presents a viewpoint that enhances understanding of these inconsistencies and can serve as a basis for customized liver interventions. Clin. Anat. 30:974-977, 2017. © 2017 Wiley Periodicals, Inc.

Laparoscopic liver resection of hepatocellular carcinoma located in segments 7 or 8

BACKGROUND

Many centers consider hepatocellular carcinoma (HCC) located in segments 7 or 8 to be unsuitable for laparoscopic liver resection (LLR). We evaluated the safety of LLR of HCC in segments 7 or 8 following the introduction of new laparoscopic techniques.

METHODS

This retrospective study included 104 patients who underwent LLR (n = 46) or open liver resection (OLR) (n = 58) for HCC located in segments 7 or 8 between October 2004 and June 2015. The LLR group was subdivided into two subgroups according to whether LLR was performed before (Lap1; n = 29) or after (Lap2; n = 17) the introduction of the Pringle maneuver, intercostal trocars, and semi-lateral patient positioning.

RESULTS

Non-anatomical resection was more frequent (63.0 vs. 29.3%; P < 0.001) and tumor size was smaller (2.8 vs. 4.7 cm; P < 0.001) in the LLR group than in the OLR group. Blood transfusion (P = 0.526), operation time (P = 0.267), postoperative complications (P = 0.051), and resection margin (P = 0.705) were similar in both groups. LLR was associated with less blood loss (550 vs. 700 ml, P = 0.030) and shorter hospital stay (8 vs. 10 days; P = 0.001). The 3-year overall (90.2 vs. 81.2%, P = 0.096) and disease-free survival (15.1 vs. 12.1%; P = 0.857) rates were similar in both groups. The Lap2 group has less blood loss (230 vs. 500 ml; P = 0.005) and shorter hospital stay (7 vs. 9 days; P = 0.038) compared with the Lap1 group.

CONCLUSION

LLR can be safely performed for HCC located in segments 7 or 8 with recent improvements in surgical techniques and accumulated experience.

Parenchymal-sparing hepatectomy for deep-placed colorectal liver metastases

BACKGROUND

The feasibility of parenchymal-sparing hepatectomy has yet to be assessed based on the tumor location, which affects the choice of treatment in patients with colorectal liver metastases.

METHODS

Sixty-three patients underwent first curative hepatectomy for deep-placed colorectal liver metastases whose center was located >30 mm from the liver surface. Operative outcomes were compared among patients who underwent parenchymal-sparing hepatectomy or major hepatectomy (≥3 segments).

RESULTS

Parenchymal-sparing hepatectomy and major hepatectomy were performed for deep-placed colorectal liver metastases in 40 (63%) and 23 (37%) patients, respectively. Resection time was longer in the parenchymal-sparing hepatectomy than in the major hepatectomy group (57 vs 39 minutes) (P = .02) and cut-surface area was wider (120 vs 86 cm²) (P < .01). Resected volume was smaller in the parenchymal-sparing hepatectomy than in the major hepatectomy group (251 vs 560 g) (P < .01). No differences were found between the 2 groups for total operation time (306 vs 328 minutes), amount of blood loss (516 vs 400 mL), rate of major complications (10% vs 13%), and positive operative margins (5% vs 4%). Overall, recurrence-free, and liver recurrence-free survivals did not differ between the 2 groups. Direct major hepatectomy without portal venous embolization could not have been performed in 40% of the parenchymal-sparing hepatectomy group (16/40) because of the small liver remnant volume.

CONCLUSION

Parenchymal-sparing hepatectomy for deep-placed colorectal liver metastases was performed safely without compromising oncologic radicality. Parenchymal-sparing hepatectomy can increase the number of patients eligible for an operation by halving the resection volume and by increasing the chance of direct operative treatment in patients with ill-located colorectal liver metastases.

Use of intercostal trocars for laparoscopic resection of subphrenic hepatic tumors

BACKGROUND

The aim of this study was to demonstrate the detailed surgical techniques of laparoscopic hepatectomy using intercostal transthoracic trocars for subcapsular tumors located in segment VII or VIII.

METHODS

Intercostal transthoracic trocars were used in patients undergoing laparoscopic hepatectomy for tumors located in segment VII or VIII. Following establishment of pneumoperitoneum and placement of abdominal trocars, balloon-tipped trocars were inserted into the abdominal cavity from the intercostal space and through the pleural space and diaphragm. Upon placement of the intercostal trocars, the lung edge was confirmed by ultrasonography and laparoscopic examination. Following minimal mobilization of the right liver, hemispherical wedge resection of segment VII or VIII was performed using the intercostal trocars as a camera port or for the forceps of the surgeon's left hand. After the hepatectomy, the holes in the diaphragm were sutured closed.

RESULTS

Among the 79 patients who underwent laparoscopic hepatectomy, intercostal trocars were used in 14 patients for resection of tumors located in segment VII (4 nodules) or VIII (10 nodules). The median (range) operation time and amount of blood loss for hepatectomy were 225 (109-477) min and 60 (20-310) mL, respectively. No postoperative complications associated with hepatectomy or the use of intercostal trocars occurred.

CONCLUSIONS

Use of intercostal transthoracic trocars is safe and effective not only for complicated laparoscopic hepatectomy but also for hemispherical wedge resections of subcapsular hepatic tumors located in segment VII or VIII.