Preoperative Portal Vein Embolization Research Articles

Survival and recurrence after hepatic resection of 386 consecutive patients with hepatocellular carcinoma

Background: Although hepatic resection is one of the most effective treatments for hepatocellular carcinoma (HCC), the longterm results of hepatic resection of this malignancy are far from satisfactory. The potential benefits of hepatectomy for patients with HCC have not been fully delineated. This study aimed to identify surgical outcomes of 386 consecutive patients with HCC undergoing hepatic resection.Study Design: The retrospective study looked at records of 293 men and 93 women. The mean age was 63.2 years. Preoperative transarterial chemoembolizaton and portal vein embolization were performed in 138 patients (35.8%) and 8 patients (2.1%), respectively. Sixty-two patients (16.1%) had major hepatectomy and the other 324 (83.9%) had minor hepatectomy. Thirty-seven of 386 patients (9.6%) had a noncurative operation.Results: The 30-day (operative) mortality rate was 4.1%, and there were 11 additional late deaths (2.9%). Two hundred fourteen of 327 patients (65.4%) had recurrence after curative resection. Unfavorable factors for survival and recurrence were resection between 1983 and 1990, Child class B or C, cirrhosis, a high value of indocyanine green retention-15, a large amount of intraoperative blood loss, stage IV disease, positive surgical margin, vascular invasion, and postoperative complications. Preoperative transarterial chemoembolization increased the recurrence rate and showed no contribution to prognosis. Currently, 106 patients (27.5%) are alive: 7 (1.8%) after more than 10 years and 43 (11.1%) after more than 5 years. Mean and median overall survivals after operation were 38 months and 29 months, respectively. The 5-year and 10-year overall or disease-free survival rates after hepatic resection were 34.4% and 10.5% or 23.3% and 7.8%, respectively.Conclusions: The longterm survival rate after operation remains unsatisfactory mainly because of the high recurrence rate. Preoperative transarterial chemoembolization should be avoided because of a high risk of postoperative recurrence. Treatment strategies for recurrent HCC may play an important role in achieving better prognosis after operation, especially in patients with more than Child class B, cirrhosis, high values of indocyanine green retention-15, massive intraoperative blood loss, stage IV disease, positive surgical margin, vascular invasion, and postoperative complica- tions.

Preoperative portal vein embolization improves prognosis after right hepatectomy for hepatocellular carcinoma in patients with impaired hepatic function.

Percutaneous transhepatic portal vein embolization (PTPE) increases the safety of subsequent major hepatectomy. The aim of this study was to determine the effect of PTPE on long-term prognosis after hepatectomy in patients with hepatocellular carcinoma (HCC). Seventy-one patients with HCC underwent right hepatectomy between 1984 and 1998. Preoperative PTPE was performed in 33 patients (group 1) and was not used in 38 patients (group 2). Outcome after operation was compared between the groups. The patients were further divided according to the median tumour diameter (cut-off 6 cm) and indocyanine green retention rate at 15 min (ICGR15) (cut-off 13 per cent). The cumulative survival rate was significantly higher in group 1 than in group 2 in patients with an ICGR15 of at least 13 per cent. Tumour-free survival rates were similar in both groups. Of patients with tumour recurrence after right hepatectomy, those in group 1 were more frequently subjected to further treatment. Preoperative PTPE improves the prognosis after right hepatectomy for HCC in patients with impaired hepatic function, although it does not prevent tumour recurrence.

Standardized measurement of the future liver remnant prior to extended liver resection: Methodology and clinical associations

Background. There is no agreement regarding the preoperative measurement of liver volumes and the minimal safe size of the liver remnant after extended hepatectomy. Methods. In 20 patients with hepatobiliary malignancy and no underlying chronic liver disease, volumetric measurements of the liver remnant (segments 2 and 3 ± 1) were obtained before extended right lobectomy (right trisegmentectomy). The ratios of future liver remnant to total liver volume were calculated by using a formula based on body surface area. In 12 patients, response to preoperative right trisectoral portal vein embolization was evaluated. In 15 patients who underwent the planned resection, preoperative volumes were correlated with biochemical and clinical outcome parameters. Results. The future liver remnants increased after portal vein embolization (26% versus 36%, P <.01). Smaller size liver remnants were associated with an increase in postoperative liver function tests (P <.05) and longer lengths of hospital stay (P <.02). Preliminary data indicates an increase in major complications for liver volumes ≤25% (P =.02). Conclusions. A simple method of measurement provides an assessment of the liver remnant before resection. It is useful in evaluating response to portal vein embolization and in predicating the outcome before extended liver resections. (Surgery 2000;127:512–9.)

Resection of nonresectable liver metastases from colorectal cancer after percutaneous portal vein embolization.

To assess the influence of preoperative portal vein embolization (PVE) on the long-term outcome of liver resection for colorectal metastases. Preoperative PVE of the liver induces hypertrophy of the remnant liver and increases the safety of hepatectomy. Thirty patients underwent preoperative PVE and 88 patients did not before resection of four or more liver segments. PVE was performed when the estimated rate of remnant functional liver parenchyma (ERRFLP) assessed by CT scan volumetry was less than 40%. PVE was feasible in all patients. There were no deaths. The complication rate was 3%. The post-PVE ERRFLP was significantly increased compared with the pre-PVE value. Liver resection was performed after PVE in 19 patients (63%), with surgical death and complication rates of 4% and 7% respectively. PVE increased the number of resections of more than four segments by 19% (17/88). Actuarial survival rates after hepatectomy with or without previous PVE were comparable: 81%, 67%, and 40% versus 88%, 61%, and 38% at 1, 3, and 5 years respectively. PVE allows more patients with previously unresectable liver tumors to benefit from resection. Long-term survival is comparable to that after resection without PVE.

Effect of Preoperative Portal Vein Embolization on Liver Volume and Hepatic Energy Status of the Nonembolized Liver Lobe in Humans

Clinically portal vein embolization (PVE) is presently preferred to extended hepatectomy. Nevertheless, its effect on hepatic adenosine triphosphate (ATP) and energy charge levels, which are essential for organ viability, has been little studied in humans. Fourteen patients with (n = 7) and without (n = 7) preoperative right PVE participated in this study. Changes in hepatic lobar volume and serum liver function tests were examined before and after percutaneous transhepatic right PVE. Liver volume (cm³) was calculated on computed tomograms before and 20 ± 3 days after PVE. At the time of surgery (mean of 25 days after PVE), small liver specimens were obtained from portal vein (PV) nonembolized left lobes immediately after laparotomy without any ischemic procedures. Concentrations of adenine nucleotides were measured by high performance liquid chromatography, and hepatic energy charge levels were calculated. These values were compared with those in control patients who had not undergone preoperative PVE. Serum liver function tests including the indocyanine green retention rate did not differ significantly before and after PVE. The volume of the PV-nonembolized left lobe significantly increased after right PVE (from 473 ± 32 to 624 ± 66 cm³), with a significant increase in the percentage of the left lobe to total liver volume. The concentrations of AMP, ADP, and ATP, and hepatic energy charge levels in the PV-nonembolized left lobe were similar to those of the control liver. These results suggest that preoperative right PVE increases the volume of the nonembolized left lobe, keeping the hepatic engery charge and ATP levels similar to the control liver, thereby increasing the total amount of ATP and hepatic energy reserve of the PV-nonembolized lobe in proportion to its volume increase at the time of surgery.

During liver regeneration following right portal embolization the growth rate of liver metastases is more rapid than that of the liver parenchyma.

The relative growth rates of human liver metastases are not known. The aim of this study was to determine in humans the growth rate of liver parenchyma during regeneration and the growth rate of liver metastases during the same process. Among 556 patients hepatectomized for a malignant lesion, 48 underwent preoperative selective right portal vein embolization to induce hypertrophy of the left lobe. Five cases were selected because a liver metastasis was present inside the regenerating left lobe. The volumes of the liver metastasis and left lobe were measured with a three-dimensional technique on pre-embolization and postembolization computed tomography (CT) or CT arterial portography. The median interval between the two measurements was 34 (range 28-40) days. An increase occurred in the volume of the liver metastasis and the left lobe in the four patients with functionally intact liver parenchyma, but not in the patient with an impaired parenchyma. The volumetric increase of the normal liver varied from 59 to 127 per cent, compared with 60 to 970 per cent for the liver metastases. The ratio between the growth rate of the left lobe and the liver metastasis varied from 1.0 to 15.6. The growth rates of two metastases in the left lobe of a single patient were different. In functionally intact liver parenchyma, during hepatic regeneration or hypertrophy, the growth rate of metastases is more rapid that that of the liver parenchyma. However, a wide variation in growth rate is observed between patients and between metastases.

Preoperative portal vein embolization: an audit of 84 patients.

Preoperative portal vein embolization (PVE) was performed in 84 patients before extensive liver resection for various diseases. By the criteria of liver volumetric determination, some patients were candidates for PVE, whereas others were not, even though the same surgical procedure, such as extended right lobectomy (ERL), was scheduled. PVE using gelatin sponge powder induced hypertrophy in the nonembolized lobe (0%-171%; median, 30%) and proportional atrophy in the embolized lobe in 2 weeks without eliciting any major inflammatory or necrotic reaction, as evidenced histologically and by the minimal elevations in the serum aspartate transaminase (AST) and alanine transaminase (ALT) values. Alterations in the total bilirubin level and prothrombin time were also insignificant and transient, indicating that hepatocyte functions were not impaired by PVE. Not all patients who undergo PVE proceed with the scheduled hepatic resection procedure, so it is a great advantage that gelatin sponge causes minimal damage compared with other embolizing materials such as cyanoacrylate and absolute ethanol, which have been reported to induce an inflammatory reaction or histological alteration. Our multiple regression analysis showed that three factors, diabetes mellitus, a high total bilirubin level at the time of PVE, and being male, each reduced the extent of hypertrophy in the nonembolized lobe (r2 =.30). By contrast, cholestasis appeared to accelerate the process of atrophy in the embolized lobe (r2 =.16). In conclusion, PVE by gelatin sponge powder is a safe and effective preoperative maneuver that induces hypertrophy of the section of the liver that will remain after partial hepatectomy.

Treatment strategy for multiple hepatic metastases of colorectal carcinoma

We describe the treatment strategy for multiple hepatic metastases of colorectal carcinoma based on a review of the literature and our own results. Although a number of studies have suggested that multiplicity or bilobar distribution of metastases is associated with poor outcome, liver resection is thought to be the only potentially curative treatment. The only contraindications to surgery are the presence of extrahepatic metastases (with the exception of resectable lung metastases) and if radical removal of all detectable tumors is not possible. Hepatectomy should be performed with the aim of maintaining a delicate balance between radical removal of tumors and the preservation of as much residual hepatic mass as possible with minimal blood loss. Surgeons should be familiar with the use of intraoperative ultrasonography, a standard adjunct to liver resection. Preoperative portal vein embolization may be indicated in selected patients as a means of inducing hypertrophy in the remaining hepatic parenchyma.

Efficacy of preoperative portal vein embolization prior to major hepatectomy for patients with impaired liver function: A retrospective study

Hepatocellular carcinoma (HCC) is often associated with chronic liver disease, such as hepatitis or cirrhosis, and this association may limit the use of surgery as a therapy, and if surgery is pursued, may give rise to postoperative hepatic failure. We evaluated the outcome in patients with HCC given preoperative portal vein embolization (PVE) before they underwent major hepatectomy. After PVE, portal pressure increased significantly. Two weeks after PVE, both the volume of the non-embolized lobe and the 15-min indocyamine green retention rate (ICG R15) were significantly increased. The prognostic score, calculated on the basis of age, ICG R15, and the resection rate, was significantly decreased. The operative mortality rate was significantly lower in patients who underwent PVE before surgery than in patients who did not receive PVE. The cumulative survival rate of the PVE patients, even those with cirrhosis of the liver, was significantly higher. Prior PVE appears to allow more extensive major hepatectomy and to lessen the risk of this invasive surgery. However, patients in whom the portal pressure immediately after PVE was more than 30cm H2O and/or whose prognostic score exceeded 50 points developed postoperative hepatic failure. These features should be kept in mind when it is decided whether surgery is indicated. Nevertheless, preoperative PVE appears to be a beneficial procedure for patients undergoing major hepatectomy, particularly those with chronic liver disease.

Preoperative percutaneous transhepatic portal embolization with absolute ethanol in patients with hepatocellular carcinoma

Preoperative percutaneous transhepatic portal vein embolization (PTPE) has been used in recent years to decrease the amount of liver resected and to reduce the risk of postoperative liver failure in patients with hepatocellular carcinoma. Various thrombogenic agents have been employed for this purpose. We evaluated the clinical safety and efficacy of absolute ethanol for PTPE and examined the histopathologic changes that follow ethanol embolization of the liver. We studied nine patients with hepatocellular carcinoma who were not originally regarded as surgical candidates because of a high risk of postoperative liver failure. They received preoperative PTPE of the right portal vein, with an average of 22.8 ml of absolute ethanol. The right lobe showed complete obstruction of portal venous branches and massive necrosis of the liver parenchyma. Macroscopically, there was atrophy of the embolized lobes and compensatory hypertrophy of the remaining lobes. The mean volume of the nonembolized lobe increased, from 351 to 585 and 633 ml, 2 and 4 weeks after embolization, respectively. The mean regeneration rate of this lobe was 16.7 cm3/day for the first 2 weeks after embolization and 10.1 cm3/day for the first 4 weeks. Transient dynamic increases in alanine aminotransferase concentrations were seen. All patients subsequently underwent right lobectomy of the liver and survived without severe complications. Portal vein embolization with absolute ethanol makes more extensive hepatectomy possible by reducing the volume necessary to resect, and it preserves the function of the remaining liver.

Preoperative transhepatic portal vein embolization for impaired residual hepatic function in patients with obstructive jaundice

Fifty patients with obstructive jaundice with biliary tract carcinoma who underwent percutaneous transhepatic portal vein embolization (PTPE) were studied to evaluate the clinical utility of PTPE in preparation for extensive liver resection. PTPE was performed 2–3 weeks before surgery, via the standard contralateral approach in the first seven patients and via the ipsilateral approach, devised by the authors, in the last 43 patients. The following portal branches in which embolization was planned were all successfully embolized: the right portal vein in 35 patients; the right portal vein plus the left medial portal branch in 6; the left portal vein and the right anterior portal branch in 3; the left portal vein in 2; the right anterior portal branch in 3; and the right posterior portal branch in 1. There were no procedure-related complications. Helical computed tomography demonstrated compensatory hypertrophy of the non-embolized segments. After PTPE, 35 of the 50 subjects underwent major hepatectomy with or without portal vein resection and/or pancreatoduodenectomy; the remaining 15 were found to have peritoneal dissemination or liver metastasis, and no resection was performed. Of the 35 hepatectomized patients, 3 died of posthepatectomy liver failure, and 1 patient died of pneumonia with pulmonary lymphangitis carcinomatosis; the other 31 patients were discharged in good condition. The hospital death rate was 11.8% (4/35), and mortality directly related to the surgery was 8.6% (3/35). PTPE appears to have the potential to increase the safety of extensive liver resection for patients with obstructive jaundice.

Fate of the human liver after hemihepatic portal vein embolization: Cell kinetic and morphometric study.

The favorable therapeutic effect of preoperative portal vein embolization (PVE) was analyzed by assessing various volumetric, cell kinetic and morphometric parameters and examining histologically the embolized and nonembolized lobes of 15 patients who underwent extended right lobectomy 2 to 3 weeks after PVE. Each lobar volume was calculated from computed tomography (CT) images, hepatocyte proliferation was evaluated by assessing proliferative cell nuclear antigen (PCNA) expression and mitosis, hepatocyte apoptosis was evaluated by the terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and the hepatocyte numerical density as well as the sinusoidal volumetric ratio (Vvs) and the mean hepatocyte volume (Cv) were calculated using morphometric methods. PVE induced hepatocyte apoptosis and atrophy of the embolized lobe (from 798 +/- 213 to 708 +/- 222 cm3; P < .05). The increased sinusoidal volume in this lobe (17.7% +/- 4.5% and 21.7% +/- 5.7%, periportal and pericentral area, respectively) may have been attributable to hepatocyte deletion. Cells in the nonembolized lobe entered a highly active phase of proliferation within 2 weeks after PVE. Further evidence of cellular proliferation was provided by the increased nonembolized lobar volume (from 379 +/- 132 to 545 +/- 130 cm3; P < .01) and numerical density of hepatocyte nuclei (Nv) (5.38 +/- 1.26 vs. 3.11 +/- 0.85 x 105/mm3; P < .01, nonembolized vs. embolized lobe, respectively). In conclusion, these results indicate that the favorable effect of PVE is attributable to a net gain of functional hepatocyte mass and/or early induction of hepatocyte proliferation following hepatectomy. (Hepatology 1997 Nov;26(5):1162-70)

Fate of the human liver after hemihepatic portal vein embolization: Cell kinetic and morphometric study

The favorable therapeutic effect of preoperative portal vein embolization (PVE) was analyzed by assessing various volumetric, cell kinetic and morphometric parameters and examining histologically the embolized and nonembolized lobes of 15 patients who underwent extended right lobectomy 2 to 3 weeks after PVE. Each lobar volume was calculated from computed tomography (CT) images, hepatocyte proliferation was evaluated by assessing proliferative cell nuclear antigen (PCNA) expression and mitosis, hepatocyte apoptosis was evaluated by the terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and the hepatocyte numerical density as well as the sinusoidal volumetric ratio (Vvs) and the mean hepatocyte volume (Cv) were calculated using morphometric methods. PVE induced hepatocyte apoptosis and atrophy of the embolized lobe (from 798 ± 213 to 708 ± 222 cm3; P &lt; .05). The increased sinusoidal volume in this lobe (17.7% ± 4.5% and 21.7% ± 5.7%, periportal and pericentral area, respectively) may have been attributable to hepatocyte deletion. Cells in the nonembolized lobe entered a highly active phase of proliferation within 2 weeks after PVE. Further evidence of cellular proliferation was provided by the increased nonembolized lobar volume (from 379 ± 132 to 545 ± 130 cm3; P &lt; .01) and numerical density of hepatocyte nuclei (Nv) (5.38 ± 1.26 vs. 3.11 ± 0.85 × 105/mm3; P &lt; .01, nonembolized vs. embolized lobe, respectively). In conclusion, these results indicate that the favorable effect of PVE is attributable to a net gain of functional hepatocyte mass and/or early induction of hepatocyte proliferation following hepatectomy.

Effect of preoperative portal vein embolization on major hepatectomy for advanced-stage hepatocellular carcinomas in injured livers: a preliminary report.

With the aim of minimizing postoperative liver dysfunction and promoting increased resectability, we employed portal vein embolization (PVE). In this study, the effect of PVE on major hepatic resection for advanced-stage hepatocellular carcinoma (HCC) in injured livers was evaluated. PVE was performed prior to hepatectomy in 13 patients with stage III and IV HCCs. Following PVE, right trisegmentectomy was performed in 3 patients, extended right lobectomy in 3 and right lobectomy in 7. To evaluate the effect of PVE, the changes in liver functional capacity and estimated remnant liver volume (ERLV), determined by computed tomography, were examined before and after PVE. The operative morbility, mortality, and survival rates after hepatectomy were also assessed. By 2 weeks after PVE, ERLV had increased in all patients, by an average of 28%, and the mean resection rates had decreased from 70.0% to 62.2%. Postoperatively, the 30-day mortality rate was 15.3%, and the 1- and 2-year survival rates were 69% and 46%, respectively. The results of this study indicate that resectability can be increased, and major hepatectomy can be made safer by employing PVE preoperatively, in view of the fact that major hepatectomy was not considered feasible without PVE in these patients.

Preoperative portal vein embolization for extension of hepatectomy indications

To render hepatectomy feasible in patients with an initially deficient volume of the future remnant liver (FRL), we redistributed portal blood flow rich in hepatotrophic substances toward the FRL. Redistribution was achieved with preoperative portal vein embolization (POPE) feeding the future resected liver. POPE was performed in 31 patients, under fluoroscopic guidance, via a percutaneous access. POPE was well tolerated and surgery was practicable in 24 patients without severe postoperative liver failure. Seven operations were cancelled, but only one due to insufficient hypertrophy of the FRL. FRL volume values were 90 to 560 mL (mean 260 mL) before POPE and 160-783 mL (mean 443 mL) after POPE, which represents a median increase of 79% +/- 50%. Hypertrophy of the FRL was 90% +/- 52% after 30 days with cyanoacrylate, 53% +/- 6% after 43 days with Gelfoam, and 44% +/- 30% after 35 days with coils. Slight shrinkage was obtained in the volume of the embolized liver, for which resection was planned. Overall survival was 2-62 months (mean 26 months), disease-free survival was 0-60 months (mean 19 months), and 7 patients are disease-free and alive 14 to 60 months (mean 43 months) after surgery. Although exclusively applicable in a limited subset of patients, POPE widens the possibilities of curative hepatectomies, because it induces sound hypertrophy of unembolized liver segments. Cyanoacrylate seems to ensure better and faster hypertrophy. (Hepatology 1996 Dec;24(6):1386-91)

Preoperative Portal Vein Embolization for Extension of Hepatectomy Indications

To render hepatectomy feasible in patients with an initially deficient volume of the future remnant liver (FRL), we redistributed portal blood flow rich in hepatotrophic substances toward the FRL. Redistribution was achieved with preoperative portal vein embolization (POPE) feeding the future resected liver. POPE was performed in 31 patients, under fluoroscopic guidance, via a percutaneous access. POPE was well tolerated and surgery was practicable in 24 patients without severe postoperative liver failure. Seven operations were cancelled, but only one due to insufficient hypertrophy of the FRL. FRL volume values were 90 to 560 mL (mean 260 mL) before POPE and 160–783 mL (mean 443 mL) after POPE, which represents a median increase of 79% ± 50%. Hypertrophy of the FRL was 90% ± 52% after 30 days with cyanoacrylate, 53% ± 6% after 43 days with Gelfoam, and 44% ± 30% after 35 days with coils. Slight shrinkage was obtained in the volume of the embolized liver, for which resection was planned. Overall survival was 2–62 months (mean 26 months), disease–free survival was 0–60 months (mean 19 months), and 7 patients are disease–free and alive 14 to 60 months (mean 43 months) after surgery. Although exclusively applicable in a limited subset of patients, POPE widens the possibilities of curative hepatectomies, because it induces sound hypertrophy of unembolized liver segments. Cyanoacrylate seems to ensure better and faster hypertrophy.

Selective percutaneous transhepatic embolization of the portal vein in preparation for extensive liver resection: the ipsilateral approach.

The ipsilateral approach was used at preoperative portal vein embolization in 38 patients with hepatobiliary malignancy. The right anterior portal branch was punctured. Two different 5.5-F triple-lumen balloon catheters were used, and fibrin glue and iodized oil were injected. Portal vein embolization was successful in all cases (right lobe, 24 patients; left lobe and right anterior segment, six; right lobe and left medial segment, three; right posterior segment, two; right anterior segment, one; left lobe, one; and right and caudate lobes, one).

Elevated mitochondrial gene expression during rat liver regeneration after portal vein ligation

We explored the molecular basis of mitochondrial energy production during rat liver regeneration after portal vein ligation. Ligation of the left branch of the portal vein induces an increase in the weight of the nonligated lobe, counterbalancing the reduced weight of the ligated lobe. Using this model, we investigated changes in mitochondrial DNA-binding proteins, mitochondrial DNA, and mitochondrial messenger RNA (mRNA) in rat hepatocytes of the nonligated lobes. The amount of mitochondrial DNA-binding protein increased maximally (200% to 300% of the preoperative level) at 12 hours after the operation, before an increase (390%) in mitochondrial DNA content at 24 hours, and parallel to an increase (240%) in mitochondrial mRNA levels at 12 hours. These results suggest that the energy supply for liver regeneration is achieved through enhancement of mitochondrial DNA replication as well as transcription, in which the mitochondrial DNA-binding proteins probably play regulatory roles. We also found that in the nonligated lobes, mRNA levels of hepatocyte growth factor increased to a detectable level only 12 hours after the operation. These molecular biochemical data help explain why preoperative portal vein embolization, which is a modification of portal vein branch ligation, is an effective method to prevent posthepatectomy liver failure.

Elevated mitochondrial gene expression during rat liver regeneration after portal vein ligation

We explored the molecular basis of mitochondrial energy production during rat liver regeneration after portal vein ligation. Ligation of the left branch of the portal vein induces an increase in the weight of the nonligated lobe, counterbalancing the reduced weight of the ligated lobe. Using this model, we investigated changes in mitochondrial DNA-binding proteins, mitochondrial DNA, and mitochondrial messenger RNA (mRNA) in rat hepatocytes of the nonligated lobes. The amount of mitochondrial DNA-binding protein increased maximally (200% to 300% of the preoperative level) at 12 hours after the operation, before an increase (390%) in mitochondrial DNA content at 24 hours, and parallel to an increase (240%) in mitochondrial mRNA levels at 12 hours. These results suggest that the energy supply for liver regeneration is achieved through enhancement of mitochondrial DNA replication as well as transcription, in which the mitochondrial DNA-binding proteins probably play regulatory roles. We also found that in the nonligated lobes, mRNA levels of hepatocyte growth factor increased to a detectable level only 12 hours after the operation. These molecular biochemical data help explain why preoperative portal vein embolization, which is a modification of portal vein branch ligation, is an effective method to prevent posthepatectomy liver failure. (Hepatology 1995; 22:1222-1229.).

Preoperative management of hilar cholangiocarcinoma

From both the therapeutic and diagnostic viewpoints, percutaneous transhepatic biliary drainage (PTBD) is crucial for the preoperative management of hilar cholangiocarcinoma. The direct anterior approach under fluoroscopic guidance is the most advantageous form of PTBD. Despite some advantages, endoscopic retrograde biliary drainage is contraindicated for preoperative biliary decompression. Pertinent multiple catheterizations using PTBD result in an accurate diagnosis of cancer extent, and produce effective relief of jaundice, as well as preventing the development of cholangitis. This, in turn, permits a rational surgical strategy and improved postoperative recovery. Preoperative staging of hilar cholangiocarcinoma is achieved by tube cholangiography through the PTBD catheter and by percutaneous transhepatic cholangioscopy. Angiography and percutaneous transhepatic portography are also recommended to diagneous extramural invasion of cancer. Prevention of posthepatectomy liver failure is the greatest challenge in the treatment of this disease. A multifactorial approach that combines several elements may provide sufficient data for determing the safe limits of surgery and for predicting posthepatectomy liver failure. Preoperative percutaneous transhepatic portal vein embolization (PTPE) is an effective method for preventing this intractable complication.