Robotic (super) microsurgery: Feasibility of a new master-slave platform in an in vivo animal model and future directions.

Advanced microsurgical procedures are currently limited by human precision and manual dexterity. The potential of robotics in microsurgery is highlighted, including a general overview of applications of robotic assistance in microsurgery and its introduction in different surgical specialties. A new robotic platform especially designed for (super) microsurgery is presented. Results of an in vivo animal study underline its feasibility and encourage further development toward clinical studies. Future directions of robotic microsurgery are proposed.

Quality of Life of Patients After Immediate or Delayed Autologous Breast Reconstruction: A Multicenter Study.

INTRODUCTION: It is known that breast reconstruction improves quality of life (QoL) in women who underwent mastectomy. Previous studies showed that autologous immediate breast reconstruction is as safe as delayed breast reconstruction. However, there is not much known about the influence of the timing of the breast reconstruction on QoL. Therefore, this study aims to assess the effect of timing of the breast reconstruction on QoL, using the BREAST-Q questionnaire. METHODS: A total of 543 patients aged 18 years or older who underwent deep inferior epigastric perforator flap reconstruction after mastectomy (for prophylactic or oncological reasons) at least 12 months ago were selected in 3 hospitals in the Netherlands and invited to complete the BREAST-Q. Mean QoL outcomes were compared between patients who underwent immediate or delayed breast reconstruction. Furthermore, QoL outcomes were compared with recently published normative data of the BREAST-Q. RESULTS: Patients who underwent immediate reconstruction reported higher scores on satisfaction with psychosocial well-being, sexual well-being, physical well-being of the chest, and physical well-being of the abdomen. Patients who underwent delayed reconstruction reported higher scores on satisfaction with breasts, outcome, and nipples. However, after adjusting for potentially influencing factors, none of the differences were significant. Compared with the normative BREAST-Q data, both of our patient groups reported higher scores on satisfaction with breasts, psychological well-being, and sexual well-being, whereas they reported lower scores on satisfaction with physical well-being of the chest and the abdomen. CONCLUSIONS: This study suggests that patients who underwent immediate or delayed deep inferior epigastric perforator flap breast reconstruction have comparable QoL more than 1 year after surgery, irrespective of the timing of the breast reconstruction.

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.

Physiological and biochemical basis of clinical liver function tests: a review.

OBJECTIVE: To review the literature on the most clinically relevant and novel liver function tests used for the assessment of hepatic function before liver surgery. BACKGROUND: Postoperative liver failure is the major cause of mortality and morbidity after partial liver resection and develops as a result of insufficient remnant liver function. Therefore, accurate preoperative assessment of the future remnant liver function is mandatory in the selection of candidates for safe partial liver resection. METHODS: A MEDLINE search was performed using the key words "liver function tests," "functional studies in the liver," "compromised liver," "physiological basis," and "mechanistic background," with and without Boolean operators. RESULTS: Passive liver function tests, including biochemical parameters and clinical grading systems, are not accurate enough in predicting outcome after liver surgery. Dynamic quantitative liver function tests, such as the indocyanine green test and galactose elimination capacity, are more accurate as they measure the elimination process of a substance that is cleared and/or metabolized almost exclusively by the liver. However, these tests only measure global liver function. Nuclear imaging techniques ((99m)Tc-galactosyl serum albumin scintigraphy and (99m)Tc-mebrofenin hepatobiliary scintigraphy) can measure both total and future remnant liver function and potentially identify patients at risk for postresectional liver failure. CONCLUSIONS: Because of the complexity of liver function, one single test does not represent overall liver function. In addition to computed tomography volumetry, quantitative liver function tests should be used to determine whether a safe resection can be performed. Presently, (99m)Tc-mebrofenin hepatobiliary scintigraphy seems to be the most valuable quantitative liver function test, as it can measure multiple aspects of liver function in, specifically, the future remnant liver.

Effects of prolonged pneumoperitoneum on hepatic perfusion during laparoscopy.

OBJECTIVE: To assess the influence of prolonged pneumoperitoneum (PP) on liver function and perfusion in a clinically relevant porcine model of laparoscopic abdominal insufflation. BACKGROUND: PP during laparoscopic surgery produces increased intra-abdominal pressure, which potentially influences hepatic function and microcirculatory perfusion. METHODS: Six pigs (49.6 ± 5.8 kg) underwent laparoscopic intra-abdominal insufflation with 14 mm Hg CO2 gas for 6 hours, followed by a recovery period of 6 hours. Two animals were subjected to 25 mm Hg CO2 gas. Hemodynamic parameters were monitored, and damage parameters in the blood were measured to assess liver injury. Liver total blood flow and function were determined by the indocyanine green (ICG) clearance test. Intraoperative hepatic hemodynamics were measured by simultaneous reflectance spectrophotometry (venous oxygen saturation StO2 and relative tissue hemoglobin concentration rHb) and laser Doppler flowmetry (blood flow and flow velocity). Postmortem liver samples were collected for histological evaluation. RESULTS: A decrease in microvascular perfusion was observed during PP. After 6 hours of PP, ICG clearance increased (P < 0.001), indicating a compensatory improvement of overall liver blood flow resulting in concomitantly improved microcirculatory perfusion (P = 0.024). Minimal parenchymal damage (aspartate aminotransferase) of the liver was seen after 6 hours of PP (P = 0.006), which seemed related to PP pressure. Minor histological damage was observed. CONCLUSIONS: The liver sustains no additional damage due to prolonged PP during laparoscopic surgery. Our findings suggest that prolonged PP does not hamper liver function or cause liver damage after extended laparoscopic procedures.

Enhanced tumor growth after portal vein embolization in a rabbit tumor model.

BACKGROUND: Preoperative portal vein embolization (PVE) is used to increase future remnant liver volume through induction of hepatocellular regeneration. This event, however, potentially enhances tumor growth. The aim of our study was to assess tumor growth and liver regeneration after PVE in a rabbit hepatic tumor model. The VX2 carcinoma is derived from a virus-induced papilloma tumor in rabbits. The tumor grows rapidly, and its blood supply is similar to that of human hepatocellular carcinoma. MATERIALS AND METHODS: Two weeks after subcapsular implantation of a VX2 carcinoma in the cranial liver lobe, New Zealand White rabbits were allocated to a control or PVE group (n = 5 per group). In the PVE group, the portal vein branch to the cranial liver lobes (80%) was embolized using particles and coils, leaving the caudal liver lobe (20%) free. In the tumor control group, the liver was mobilized. Computed tomography volumetry was performed on days 3, 7, 10, and 14. Tumor growth rate (TGR), hepatocellular proliferation rate, and liver damage parameters were assessed before PVE and on days 1, 3, 7, 10, and 14. RESULTS: Portography confirmed complete occlusion of the portal vein branch to the cranial liver lobes in all PVE rabbits. The hypertrophy response and proliferation rate in the nonembolized liver lobes were significantly higher in the PVE group, which was confirmed by liver-to-body weight index assessment. TGR was increased in both groups, with a significantly larger increase in the PVE group over time (day 14: mean, 34.4 ± 4.3 mL/d versus control: mean, 24.1 ± 7.2 mL/d; P < 0.05). CONCLUSIONS: TGR was significantly increased after PVE in the rabbit tumor model. This finding supports the notion that PVE potentially enhances tumor growth, along with the regeneration of the nonembolized liver lobe.

Staging laparoscopy in patients with hepatocellular carcinoma: is it useful?

BACKGROUND: Staging laparoscopy (SL) is not regularly performed for patients with hepatocellular carcinoma (HCC). It may change treatment strategy, preventing unnecessary open exploration. An additional advantage of SL is possible biopsy of the nontumorous liver to assess fibrosis/cirrhosis. This study aimed to determine whether SL for patients with HCC still is useful. METHODS: Patients with HCC who underwent SL between January 1999 and December 2011 were analyzed. Their demographics, preoperative imaging studies, surgical findings, and histology were assessed. RESULTS: The 56 patients (34 men and 22 women; mean age, 60 ± 14 years) in this study underwent SL for assessment of extensive disease or metastases. For two patients, SL was unsuccessful because of intraabdominal adhesions. For four patients (7.1 %), SL showed unresectability because of metastases (n = 1), tumor progression (n = 1), or severe cirrhosis in the contralateral lobe (n = 2). An additional five patients did not undergo laparotomy due to disease progression detected on imaging after SL. Exploratory laparotomy for the remaining 47 patients showed 6 (13 %) additional unresectable tumors due to advanced tumor (n = 5) or nodal metastases (n = 1). Consequently, the yield of SL was 7 % (95 % confidence interval (CI), 3-17 %), and the accuracy was 27 % (95 % CI, 11-52 %). A biopsy of the contralateral liver was performed for 45 patients who underwent SL, leading to changes in management for 4 patients (17 %) with cirrhosis. CONCLUSIONS: The overall yield of SL for HCC was 7 %, and the accuracy was 27 %. When accurate imaging methods are available and additional percutaneous liver biopsy is implemented as a standard procedure in the preoperative workup of patients with HCC, the benefit of SL will become even less.

Effect of hepatic artery embolization on liver hypertrophy response in a rabbit liver VX2 tumor model.

BACKGROUND: Portal vein embolization not only induces hypertrophy of the non-embolized liver, but also enhances tumor growth. The latter could be prevented by embolizing the hepatic arteries supplying the tumor-bearing liver segments. This study aimed to determine the effects of transcatheter arterial embolization (TAE) on tumor volume and liver regeneration in a rabbit VX2 tumor model. METHODS: Twenty-three rabbits underwent subcapsular tumor implantation with a VX2 tumor. Two weeks after implantation, 18 rabbits were used for TAE experiments, 5 were for sham controls. Tumor response and liver regeneration response of the embolized cranial and non-embolized caudal liver lobes were assessed by CT volumetry, liver to body weight index, and the amount of proliferating hepatocytes. RESULTS: All super-selective arterial tumor embolization procedures were performed successfully. Despite embolization, the tumor volume increased after an initial steady state. The tumor volume after embolization was smaller than that of the sham group, but this difference was not significant. Massive necrosis of the tumor, however, was seen after embolization, without damage of the surrounding liver parenchyma. There was a significant atrophy response of the tumor bearing cranial lobe after super-selective arterial embolization of the tumor with a concomitant hypertrophy response of the non-embolized, caudal lobe. This regeneration response was confirmed histologically by a significantly higher number of proliferating hepatocytes on the Ki-67 stained slides. CONCLUSIONS: Super-selective, bland arterial coil embolization causes massive necrosis of the tumor, despite increase of volume on CT scan. Atrophy of the tumor bearing liver lobe is seen after arterial embolization of the tumor with a concomitant hypertrophy response of the non-embolized lobe, despite absence of histological damage of the tumor-surrounding liver parenchyma.

Tumor progression after preoperative portal vein embolization.

OBJECTIVE: To evaluate tumor growth in a series of patients undergoing liver resection after portal vein embolization (PVE). BACKGROUND: The regenerative response after PVE leading to compensatory hypertrophy of the nonembolized liver segments potentially enhances tumor growth. METHODS: Portal vein embolization was performed in 28 patients diagnosed with colorectal metastases between 2004 and 2011. Tumor volume was measured by computed tomography (CT) volumetry before and after PVE. Tumor growth rate (TGR) was measured by CT volumetry and compared with that of a non-PVE control group with colorectal metastases of whom 30 had 2 CT scans preoperatively. Also, newly diagnosed tumors in the future remnant liver (FRL) after PVE and after resection were analyzed. RESULTS: The median TGR of PVE patients was 0.53 mL/d (interquartile range [IQR], 0.02-1.88) versus 0.09 mL/d (IQR, -0.04 to 0.40; P = 0.03) in non-PVE patients. The TGR was 0.15 (IQR, -0.52 to 0.66) mL/d before PVE and 0.85 (IQR, -0.10 to 1.62) mL/d after PVE in the same patients (P = 0.03). Seven patients (25%) showed new tumor lesions in the FRL after PVE, of whom 3 patients (11%) were not resectable. Patients (8 of 19; 42%) after PVE also showed a higher rate of recurrent metastases in the remnant liver at follow-up than non-PVE patients (1 of 28; 4%). Survival was significantly better for non-PVE patients, with a 3-year survival rate of 77% versus 26% in patients undergoing PVE. CONCLUSIONS: Portal vein embolization is associated with increased TGR and new tumor in the FRL and recurrent tumor after resection. Short intervals and interval chemotherapy between PVE and resection are, therefore, advised.

Bile salts predict liver regeneration in rabbit model of portal vein embolization.

BACKGROUND: Portal vein embolization (PVE) is employed to increase future remnant liver (FRL) volume through induction of hepatocellular regeneration in the nonembolized liver lobe. The regenerative response is commonly determined by CT volumetry after PVE. The aim of the study was to examine plasma bile salts and triglycerides in the prediction of the regenerative response following PVE. METHODS: PVE of the cranial liver lobe was performed in 15 rabbits, divided into three groups: NaCl (control), gelatin sponge (short-term occlusion), and polyvinyl alcohol particles with coils (PVAc, long-term occlusion). In all rabbits CT volumetry and blood sampling were performed prior to PVE and on days 3 and 7. Plasma bile salts and triglycerides were correlated with volume increase of the nonembolized liver lobe. RESULTS: After 3 and 7 d, respectively, FRL volume was increased in both embolized groups, with the largest hypertrophy response observed in the PVAc group. Plasma bile salt levels were increased after PVE, especially in the PVAc group at day 3 (P < 0.01 compared to gelatin sponge). Plasma bile salts at day 3 predicted FRL volume increase at day 7 showing a positive correlation of 0.811 (P < 0.001). Levels of triglycerides were not significantly altered in either of the PVE procedures. CONCLUSIONS: Plasma bile salt levels early after PVE strongly correlated with the regenerative response in a rabbit model of PVE, showing more pronounced elevation with larger volume increase of the nonembolized lobe. Therefore, plasma bile salts, but not triglycerides, can be used in the prediction of the regenerative response after PVE.

Can plasma bile salt, triglycerides, and apoA-V levels predict liver regeneration?

BACKGROUND: Preoperative portal vein embolization (PVE) is used to increase the future remnant liver (FRL) in patients requiring extensive liver resection. Computed tomography (CT) volumetry, performed not earlier than 3-6 weeks after PVE, is commonly employed to assess hypertrophy of the FRL following PVE. Early parameters to predict effective hypertrophy are therefore desirable. The aim of the present study was to assess plasma bile salt levels, triglycerides (TG), and apoA-V in the prediction of the hypertrophy response during liver regeneration. METHODS: Serum bile salt, TG, and apoA-V levels were determined in 20 patients with colorectal metastases before PVE, and 5 h, 1, and 21 days after PVE, as well as prior to and after (day 1-7, and day 21) subsequent liver resection. These parameters were correlated with liver volume as measured by CT volumetry (%FRL-V), and liver function was determined by technetium-labeled mebrofenin hepatobiliary scintigraphy using single photon emission computed tomography. RESULTS: Triglyceride levels at baseline correlate with volume increase of the future remnant liver (FRL-V) post-PVE. Also, bile salts and TG 5 h after PVE positively correlated with the increase in FRL volume (r=0.672, p=0.024; r=0.620, p=0.042, resp.) and liver function after 3 weeks (for bile salts r=0.640, p=0.046). Following liver surgery, TG levels at 5 h and 1 day after resection were associated with liver remnant volume after 3 months (r=0.921, p=0.026 and r=0.981, p=0.019, resp). Plasma apoA-V was increased during liver regeneration. CONCLUSIONS: Bile salt and TG levels at 5 h after PVE/resection are significant early predictors of liver volume and functional increase. It is suggested that these parameters can be used for early timing of volume assessment and resection after PVE.

Posthepatectomy bile leakage: how to manage.

BACKGROUND: Biliary leakage after liver resection continues to be reported. Management of bile leakage has changed in recent years, with nowadays non-surgical procedures as the preferred treatment. METHODS: Biliary leakage and management were assessed in 381 patients who underwent liver resection between January 2005 and April 2011. RESULTS: The overall rate of biliary leakage after liver resection was 5.0%, with a higher incidence in patients who had undergone concomitant hepaticojejunostomy (HJ; 13.6 vs. 3.2%). Hospital stay (p = 0.047), major resections (p = 0.018), operation time (p = 0.011), and relaparotomy (p = 0.002) were risk factors for postoperative bile leakage. Multivariate analysis identified relaparotomy as an independent factor (OR 4.216, p = 0.034). Bile leakage in patients without HJ (n = 10) was managed in 6 patients by percutaneous transhepatic biliary drainage (PTD), and in 3 patients by endoscopic drainage. One patient was treated surgically. All patients with an HJ and postoperative bile leakage (n = 9) underwent PTD. CONCLUSION: The incidence of posthepatectomy biliary leakage has decreased over time, while PTD and endoscopic stenting are effective treatment modalities. PTD is the treatment of choice in bile leakage after resection combined with HJ.

Vascular occlusion or not during liver resection: the continuing story.

BACKGROUND: Vascular occlusion can be applied during liver resection to reduce blood loss. Herein, we provide an update of the current evidence concerning vascular occlusion. METHODS: A systematic literature search was conducted to review the effects of liver in- and outflow occlusion techniques during liver resection, focusing on blood loss and hepatic ischemia-reperfusion injury. RESULTS: The Pringle maneuver (PM) is effective in controlling blood loss; however, there is no indication for routine vascular clamping during hepatic resection in uncomplicated patients. During complex resections and in patients with abnormal liver parenchyma, the intermittent PM is preferred over continuous clamping. Total hepatic vascular exclusion (THVE) is indicated only in resection of tumors involving the inferior caval vein or the caval hepatic junction. THVE can be applied with the preservation of caval vein flow. This mode of selective hepatic vascular exclusion results in less blood loss in combination with the PM. CONCLUSION: If clamping is necessary during complex resections or in abnormal liver parenchyma, intermittent PM is advised. THVE or selective hepatic vascular exclusion may be considered in tumors involving the inferior caval vein or the caval hepatic junction. There is no evidence supporting the use of ischemic preconditioning, maintenance of a low central venous pressure or of pharmacological interventions during liver resection.

Predictors of posthepatectomy ascites with or without previous portal vein embolization.

AIM: To identify predictors of postoperative ascites after liver resection for patients with or without preoperative portal vein embolization (PVE). METHODS: Patients undergoing PVE prior to hepatectomy (PVE group; n = 37) were compared with patients who underwent liver resection without PVE (n = 503). Ascites was defined as postoperative daily drainage of clear ascitic fluid exceeding 200 ml/day. Pre-, intra-, and postoperative variables were retrospectively analyzed using uni- and multivariate analyses. RESULTS: Postoperative ascites was present in 13.5% (5/37) of patients who underwent PVE before hepatectomy, compared to 5.8% (29/503) in the group undergoing liver resection without PVE (p = 0.061). In all patients, cirrhosis (OR 54.505, p < 0.001), operation time (OR 1.004, p = 0.014), and the use of the Pringle maneuver (OR 2.336, p = 0.041) were independent risk predictors for ascites in multivariate analysis. In PVE patients, cirrhosis (OR 0.156, p < 0.001) was the only independent significant predictor of ascites after resection. In patients undergoing liver resection without PVE, independent risk factors with multivariate analysis were operation time (OR 1.005, = 0.001) and cirrhosis (OR 26.609, p < 0.001). CONCLUSION: Operation time and the use of the Pringle maneuver were significant predictors of ascites after hepatectomy. Cirrhosis was a significant risk factor associated with postoperative ascites.

Hyperbaric oxygen treatment for mastectomy flap ischaemia: A case series of 50 breasts.

INTRODUCTION: Hyperbaric oxygen treatment (HBOT) has been suggested as an effective intervention to limit necrosis of ischaemic skin flaps after mastectomy. The purpose of this study was to evaluate outcomes of HBOT in the largest series of patients to date with mastectomy flap ischaemia. METHODS: A retrospective analysis was performed of 50 breasts requiring HBOT for mastectomy flap ischaemia. The severity of the ischaemia or necrosis was evaluated by four independent observers using the skin ischaemia necrosis (SKIN) score. Multivariate logistic regression analyses were used to assess associations between risk factors and re-operation. RESULTS: HBOT was started a median of 3 days (range 1-23) after surgery and continued for a median of 12 sessions (range 6-22). The breast SKIN surface area scores (n = 175 observations by the independent observers) improved in 34% (of observations) and the depth scores deteriorated in 42% (both P < 0.01). Both the surface area and depth scores were associated with the need for re-operation: higher scores, reflecting more severe necrosis of the mastectomy flap, were associated with increased need for re-operation. Twenty-nine breasts (58%) recovered without additional operation. Pre-operative radiotherapy (OR 7.2, 95% CI 1.4-37.3) and postoperative infection (OR 15.4, 95% CI 2.6-89.7) were risk factors for re-operation in multivariate analyses. CONCLUSIONS: In this case series, the surface area of the breast affected by ischaemia decreased during HBOT, and most breasts (58%) did not undergo an additional operation. A randomised control trial is needed to confirm or refute the possibility that HBOT improves outcome in patients with mastectomy flap ischaemia.

Preclinical Experience Using a New Robotic System Created for Microsurgery.

BACKGROUND: Robotic assistance in microsurgery could enhance human precision and dexterity to improve clinical outcomes. Because no robotic device has been designed primarily for microsurgery, the authors developed a dedicated microsurgical robotic system. This preclinical study investigates whether microsurgical anastomosis can be successfully completed on silicone vessels using a prototype of this new robotic system, and compares outcomes of robot-assisted versus conventional microsurgery. METHODS: Three participants at different levels of microsurgical training completed 10 anastomoses by hand and 10 anastomoses with robotic assistance. Four blinded, experienced microsurgeons evaluated the quality of the microsurgical skills using a modified version of the Structured Assessment of Microsurgical Skills. Time to perform the anastomosis and adverse events were recorded. RESULTS: The total time to perform the anastomoses with and without robotic assistance decreased to 35.1 minutes and 12.5 minutes, respectively, during the study. The overall performance and indicative skill of the Structured Assessment of Microsurgical Skills improved with the conventional method (from 2.8 to 3.6 and from 2.6 to 3.7, respectively) and the robot-assisted method (from 2.3 to 3.0 and from 2.3 to 3.1, respectively). CONCLUSIONS: It is feasible to complete anastomotic microsurgery on silicone vessels using the MicroSure robotic system. In comparison with the conventional method, time to perform the anastomosis was longer and quality of microsurgical skills was lower in the robot-assisted group. However, the robot-assisted performance showed steeper learning curves for both surgical time and domains of microsurgical skills. The encouraging results indicate further development of the system and (pre)clinical trials.

[A man with multiple erythematous and hyperpigmented papules]. / Een man met erythemateuze, gehyperpigmenteerde papels.

A 25-year-old male patient developed multiple polycyclic papules after he had been involved in a bombardment in Syria and was hit by metal particles. We recognized the lesions as keloids, a fibroproliferative condition with abundant scar tissue. Our patient was treated with intralesional glucocorticoid injections and pressure therapy.

Management of giant liver hemangiomas: an update.

Liver hemangiomas are the most common benign liver tumors and are usually incidental findings. Liver hemangiomas are readily demonstrated by abdominal ultrasonography, computed tomography or magnetic resonance imaging. Giant liver hemangiomas are defined by a diameter larger than 5 cm. In patients with a giant liver hemangioma, observation is justified in the absence of symptoms. Surgical resection is indicated in patients with abdominal (mechanical) complaints or complications, or when diagnosis remains inconclusive. Enucleation is the preferred surgical method, according to existing literature and our own experience. Spontaneous or traumatic rupture of a giant hepatic hemangioma is rare, however, the mortality rate is high (36-39%). An uncommon complication of a giant hemangioma is disseminated intravascular coagulation (Kasabach-Merritt syndrome); intervention is then required. Herein, the authors provide a literature update of the current evidence concerning the management of giant hepatic hemangiomas. In addition, the authors assessed treatment strategies and outcomes in a series of patients with giant liver hemangiomas managed in our department.

Accurate quantitation of Ki67-positive proliferating hepatocytes in rabbit liver by a multicolor immunohistochemical (IHC) approach analyzed with automated tissue and cell segmentation software.

Determination of hepatocyte proliferation activity is hampered by the presence of Ki67-positive non-parenchymal cells. We validated a multicolor immunohistochemical (IHC) approach using multispectral tissue and cell segmentation software. Portal vein branches to the cranial liver lobes of 10 rabbits were embolized, leading to atrophy of the cranial lobes and hyperplasia of the caudal lobes. Slides from cranial and caudal lobes (n=20) were double-stained (CK8+18 and Ki67) and triple-stained (CK8+18, Ki67, and CD31). The Ki67 proliferation index was calculated using automated tissue and cell segmentation software and compared with manual counting by two independent observers. A substantial variation was seen in the number of Ki67-positive hepatocytes in the different specimens in both double and triple staining (range, 0-50). Correlation coefficients between manual counting and the digital analysis were 0.76 for observer 1 (p<0.001) and 0.78 for observer 2 (p<0.001) with double staining and R(2) = 0.91 for observer 1 and R(2) = 0.89 for observer 2, p<0.001 with triple staining. In conclusion, in rabbit, the hepatocellular proliferation index can be reliably determined using automated tissue and cell segmentation software in combination with IHC multiple staining. Our findings may be useful in clinical practice when Ki67 proliferation index yields prognostic significance.

[Giant haemangioma of the liver: diagnosis and treatment]. / Het reuzenhemangioom in de lever: diagnostiek en behandeling.

A liver haemangioma is a benign, usually small tumour comprised of blood vessels, which is often discovered coincidentally; giant haemangiomas are defined as haemangiomas larger than 5 cm. The differential diagnosis includes other hypervascular tumours, such as hepatocellular adenoma, hepatocellular carcinoma, metastasis of a neuro-endocrine tumour or renal cell carcinoma.- The diagnosis is based on abdominal ultrasonography and can be confirmed by a CT or MR scan. A wait-and-see approach is justified in patients without symptoms or with minimal symptoms, even in the presence of a giant haemangioma. Surgical resection of a giant haemangioma is only necessary when the preoperative diagnosis is inconclusive, or when the haemangioma leads to mechanical symptoms or complications. Extirpation is the only effective form of treatment of the giant haemangioma; enucleation is preferred over partial liver resection. A known complication of a giant haemangioma is the occurrence of disseminated intravascular coagulation, the Kasabach-Merritt syndrome; intervention is then demanded.