Stepwise introduction of laparoscopic liver surgery: validation of guideline recommendations.

BACKGROUND: Uncontrolled introduction of laparoscopic liver surgery (LLS) could compromise postoperative outcomes. A stepwise introduction of LLS combined with structured training is advised. This study aimed to evaluate the impact of such a stepwise introduction. METHODS: A retrospective, single-center case series assessing short term outcomes of all consecutive LLS in the period November 2006-January 2017. The technique was implemented in a stepwise fashion. To evaluate the impact of this stepwise approach combined with structured training, outcomes of LLS before and after a laparoscopic HPB fellowship were compared. RESULTS: A total of 135 laparoscopic resections were performed. Overall conversion rate was 4% (n = 5), clinically relevant complication rate 13% (n = 18) and mortality 0.7% (n = 1). A significant increase in patients with major LLS, multiple liver resections, previous abdominal surgery, malignancies and lesions located in posterior segments was observed after the fellowship as well as a decrease in the use of hand-assistance. Increasing complexity in the post fellowship period was reflected by an increase in operating times, but without comprising other surgical outcomes. CONCLUSION: A stepwise introduction of LLS combined with structured training reduced the clinical impact of the learning curve, thereby confirming guideline recommendations.

Future remnant liver function as predictive factor for the hypertrophy response after portal vein embolization.

BACKGROUND: Preoperative portal vein embolization is widely used to increase the future remnant liver. Identification of nonresponders to portal vein embolization is essential because these patients may benefit from associating liver partition and portal vein ligation for staged hepatectomy (ALPPS), which induces a more powerful hypertrophy response. 99mTc-mebrofenin hepatobiliary scintigraphy is a quantitative method for assessment of future remnant liver function with a calculated cutoff value for the prediction of postoperative liver failure. The aim of this study was to analyze future remnant liver function before portal vein embolization to predict sufficient functional hypertrophy response after portal vein embolization. METHODS: Sixty-three patients who underwent preoperative portal vein embolization and computed tomography imaging were included. Hepatobiliary scintigraphy was performed to determine pre-portal vein embolization and post-portal vein embolization future remnant liver function. Receiver operator characteristic analysis of pre-portal vein embolization future remnant liver function was performed to identify patients who would meet the post-portal vein embolization cutoff value for sufficient function (ie, 2.7%/min/m2). RESULTS: Mean pre-portal vein embolization future remnant liver function was 1.80% ± 0.45%/min/m2 and increased to 2.89% ± 0.97%/min/m2 post-portal vein embolization. Receiver operator characteristic analysis in 33 patients who did not receive chemotherapy revealed that a pre-portal vein embolization future remnant liver function of ≥1.72%/min/m2 was able to identify patients who would meet the safe future remnant liver function cutoff value 3 weeks after portal vein embolization (area under the curve = 0.820). The predictive value was less pronounced in 30 patients treated with neoadjuvant chemotherapy (area under the curve = 0.618). A total of 45 of 63 patients underwent liver resection, of whom 5 of 45 developed postoperative liver failure; 4 of 5 patients had a post-portal vein embolization future remnant liver function below the cutoff value for safe resection. CONCLUSION: When selecting patients for portal vein embolization, future remnant liver function assessed with hepatobiliary scintigraphy can be used as a predictor of insufficient functional hypertrophy after portal vein embolization, especially in nonchemotherapy patients. These patients are potential candidates for ALPPS.

Liver related complications in unresectable disease after portal vein embolization.

BACKGROUND: Portal vein embolization (PVE) is used preoperatively in patients to increase future remnant liver volume (FRLV). Unfortunately, some patients are found to be unresectable at exploration due to tumor progression or new lesions. The aim of this study is to evaluate the long-term effects of PVE in the embolized liver lobe when left unresected. METHODS: Of 85 patients who underwent right PVE, 16 (19%) were unresectable (PVE-group). These patients were compared with 48 randomly matched patients from a pool of 75 unresectable patients who had not undergone PVE. Primary outcome parameter was occurrence of infectious complications (liver abscesses) on follow-up imaging of the liver. The long-term volumetric changes of the hypertrophy/atrophy complex were assessed as secondary outcome parameter. RESULTS: Five of 16 (31%) patients in PVE-group developed an abscess vs. 4 (8%) patients in non-PVE group (P=0.022). The volume distribution of left and right liver lobes (hypertrophy-atrophy rate) increased from 26%:74% before embolization to 36%:64% three weeks after PVE and to 51%:49% six months after PVE. CONCLUSIONS: Persistence of embolized liver lobe in unresectable patients after PVE resulted in abscesses in 31%. This observation calls for developing reversible embolization techniques using absorbable materials in patients with uncertain resectability.

A review of animal models for portal vein embolization.

BACKGROUND: Portal vein embolization (PVE) is a preoperative intervention to increase the future remnant liver (FRL) through regeneration of the non-embolized liver lobes. This review assesses all the relevant animal models of PVE available, to guide researchers who intend to study PVE. MATERIALS AND METHODS: We performed a systematic literature search in Medline and Pubmed, from 1993-June 2013, using search headings "PVE" and "portal vein ligation". Articles were included when meeting the selection criteria: experimental animal study on PVE or portal vein ligation and experiments described in 5 animals or more. RESULTS: Sixty-one articles were selected, describing six different animal models. Most articles reported experiments with rats, rabbits, and pigs. In rats, the increase in wet-weight ratio of the non-occluded liver or total liver weight is greatest in the first 7 d with values ranging from 75%-80.5% on day 7. The volume increase of FRL in the rabbit model is greatest in the first 7 d with values ranging from 33.6%-80% on day 7. In pigs, the largest gain in volume of the FRL was seen in the first 2 wk. CONCLUSIONS: The choice of the model depends on the specific aim of the study. Evaluating the increase in liver volume and liver function after PVE, larger animals as the pig, rabbit, or the dog is useful because of the possibility to apply computed tomography volumetry. To evaluate mechanisms of regeneration after PVE, the rat model is useful, because of the variety of antibodies commercially available.

[Treatment of colorectal liver metastasis at a regional hospital versus a university medical centre]. / Chirurgische behandeling van colorectale levermetastasen in een perifeer en een academisch ziekenhuis.

OBJECTIVE: To evaluate the results of this type of liver surgery performed at a specialised regional hospital in comparison with the operation performed at a university medical centre (UMC). DESIGN: Prospective study at 2 hospitals. METHODS: All patients with colorectal liver metastasis who had undergone a partial liver resection and/or radiofrequency ablation (RFA) at Amphia Hospital or at the Academic Medical Centre - University of Amsterdam (AMC) from January 2005-June 2011 were included. Data on patient characteristics, type of operation, pathology results and (disease-free) survival were collected. The primary outcome measures were surgical complications and survival. RESULTS: A total of 232 patients were included. No difference in patient characteristics between centres was identified. At the AMC, 121 patients (98.4%) had undergone a resection; 6 in combination with RFA. Two patients (1.6%) had only undergone RFA. At Amphia Hospital, 85 patients (78%) had undergone a resection; 30 in combination with RFA. In 24 patients (22%), only RFA was performed. There was significant difference in the type of treatment (p < 0.01). Not significantly different between centres were the average lengths of hospital stays, surgical complications and recurrence rates. After resection, no significant differences in the 1- and 3-year (disease-free) survival rates were found between the centres. At Amphia Hospital, the overall survival at 1, 3 and 5 years was 86, 47 and 29%, respectively. These rates were significantly better at AMC with 91, 78 and 53%, respectively (p < 0.05). The difference in (disease-free) survival for the entire group of patients can be explained by the more frequent performance of RFA at Amphia Hospital. CONCLUSIONS: Postoperative morbidity, mortality and survival rates after liver surgery obtained from a specialised regional hospital are similar to results obtained from a UMC.