Patterns of failure following curative resection of colorectal liver metastases

Intraarterial Chemotherapy for Liver Metastases

Colorectal cancer (CRC) is one of the leading cancers globally in terms of both incidence and cancer-related mortality. Liver metastatic disease is the main prognostic driver for patients with CRC. The management options for liver metastatic CRC continue to evolve, particularly with the incorporation of locoregional therapies into the treatment paradigm. Hepatic arterial infusion (HAI) chemotherapy is one such liver directed approach used with the goal of converting patients to liver resection, reducing the risk of recurrence, treating recurrent disease, and most importantly improving overall survival. This article summarizes the role of HAI chemotherapy in the treatment of liver metastatic CRC.

Early Recurrence After Initial Hepatectomy for Colorectal Liver Metastases

Objective

This study investigated the frequency of early recurrence in patients who had undergone hepatectomy for colorectal cancer liver metastasis (CRLM) and assessed the indications for adjuvant chemotherapy in these patients.

Methods

This retrospective analysis included 133 consecutive patients who underwent initial hepatectomy for CRLM between April 2000 and May 2010 and have been followed more than 5 years.

Results

Of the 133 patients, 83 (62%) experienced tumor recurrence, with 14 of the 83 recurrences within 6 months after initial hepatectomy. Overall survival was significantly poorer in patients with recurrences within 6 months than those without any recurrence (P = 0.015). The frequency of adjuvant chemotherapy was significantly lower in patients with recurrences within 6 months than those without recurrences within 6 months. Multivariate analysis showed that H-2 classification was the only independent risk factor for recurrence within 6 months after hepatectomy (P = 0.002). Adjuvant chemotherapy improved prognosis in patients classified as H2.

Conclusions

Patients who experienced tumor recurrence within 6 months after initial hepatectomy for CRLM had a poorer prognosis than patients who experienced recurrence after 6 months. Patients with H2-classification of CRLM should receive preoperative adjuvant chemotherapy.

Hepatic Arterial Infusion Pumps: What the Radiologist Needs to Know

Hepatic arterial infusion (HAI) entails the surgical implantation of a subcutaneous pump to deliver chemotherapeutic agents directly to the liver in the setting of primary or secondary liver cancer. The purpose of HAI chemotherapy is to maximize hepatic drug concentrations while minimizing systemic toxicity, facilitating more effective treatment. HAI is used in combination with systemic chemotherapy and can be considered in several clinical scenarios, including adjuvant therapy, conversion of unresectable disease to resectable disease, and unresectable disease. Radiologists are key members of the multidisciplinary team involved in the selection and management of these patients with complex liver disease. As these devices begin to be used at more sites across the country, radiologists should become familiar with the guiding principles behind pump placement, expected imaging appearances of these devices, and potential associated complications. The authors provide an overview of HAI therapy, with a focus on the key imaging findings associated with this treatment that radiologists may encounter. ^©RSNA, 2021.

Intraarterial Chemotherapy for Liver Metastases

Colorectal cancer (CRC) is one of the leading cancers globally in terms of both incidence and cancer-related mortality. Liver metastatic disease is the main prognostic driver for patients with CRC. The management options for liver metastatic CRC continue to evolve, particularly with the incorporation of locoregional therapies into the treatment paradigm. Hepatic arterial infusion (HAI) chemotherapy is one such liver directed approach used with the goal of converting patients to liver resection, reducing the risk of recurrence, treating recurrent disease, and most importantly improving overall survival. This article summarizes the role of HAI chemotherapy in the treatment of liver metastatic CRC.

Stereotactic radiofrequency ablation (SRFA) for recurrent colorectal liver metastases after hepatic resection

BACKGROUND

To evaluate the efficacy, safety and overall clinical outcome of multiprobe SRFA as a treatment for recurrent colorectal liver metastases after hepatic resection (HR).

METHODS

A retrospective, single center study carried out between 2006 and 2018. 64 consecutive patients with recurrent or new CRLM after previous HR were treated by SRFA for 217 lesions (median size 2.7 cm, 1-7.5) in 103 ablation sessions. Endpoints consisted of i) technical efficacy ii) complication and mortality rates iii) local and distant recurrence, iv) disease free survival (DFS), and v) overall survival (OS).

RESULTS

213/217 tumors were successfully ablated at initial SRFA (97.7% primary technical efficacy rate). Four tumors required repeat ablation, resulting in a secondary technical efficacy rate of 99.5% (216/217). Local recurrence developed in 25/217 lesions (11.5%). Major complication rate was 5.8% (6/103 sessions) and mortality rate was 1.0% (1/103 ablation sessions), respectively.1-, 3-, and 5- year OS rates from date of first SRFA were 90.1%, 46.2%, and 34.8% (median 33.1 months). DFS rates were 54.2%, 17.2%, and 17.2%, at 1-, 3- and 5- years, respectively (median 13.3 months).

CONCLUSION

SRFA is a safe, feasible and effective option for CRLM after HR with low morbidity levels and favorable clinical outcome.

Extrahepatic recurrence rates in patients receiving adjuvant hepatic artery infusion and systemic chemotherapy after complete resection of colorectal liver metastases

BACKGROUND

This study investigated the effect of the reduced dose of systemic chemotherapy (SYS) on recurrence patterns in patients receiving adjuvant hepatic artery infusion (HAI) chemotherapy after complete colorectal liver metastases (CRLM) resection.

METHODS

Patients undergoing complete CRLM resection between 2000 and 2007 were selected from a prospectively maintained database and categorized as receiving SYS or HAI + SYS. Those with pre and/or intraoperative extrahepatic disease, documented death, or recurrence within 30 days of CRLM resection were excluded. Competing risk, Fine and Gray's tests were used to compare SYS versus HAI + SYS for time-to-organ recurrence.

RESULTS

Of 361 study patients, 153 (42.4%) received SYS and 208 (57.6%) received HAI + SYS. The median follow-up for survivors was 100 (range = 12-185) and 156 months (range = 18-217) for SYS and HAI + SYS, respectively. The 5-year cumulative incidence (CI) of any liver recurrence was greater for those receiving SYS (SYS = 41.9% vs. HAI + SYS = 28.6%, p = .005). The 5-year CI of developing any lung or extrahepatic recurrence for SYS patients was 36.2% and 47.9% compared with 44.5% (p = .242) and 51.7% (p = .551), respectively, in patients receiving HAI + SYS.

CONCLUSION

Despite the reduced dose of SYS, adjuvant HAI + SYS after CRLM resection is not associated with a significantly increased risk of extrahepatic recurrence.

Treatment Options in Colorectal Liver Metastases: Hepatic Arterial Infusion

BACKGROUND

The liver is the most common site for metastases from colorectal cancer (CRC) with the majority of these patients having unresectable disease.

METHODS

This is a retrospective review of studies using hepatic arterial infusion (HAI) therapy to treat liver metastasis from CRC. A PubMed search of randomized controlled trials and retrospective studies from 2006 to present was conducted using the search terms 'hepatic arterial infusion (HAI) therapy', 'colorectal cancer', and 'treatment of liver metastases'.

RESULTS

The first randomized studies comparing HAI to systemic therapy with 5-fluorouracil/leucovorin produced significantly higher response rates of 41 versus 14%. Systemic therapy has improved with the addition of irinotecan and oxaliplatin; however, the responses with HAI and these modern agents have also increased, with responses as high as 80%. For patients with wild-type KRAS, HAI and systemic therapy produced a median survival of 68 months. In patients with refractory disease, response rates are in the 30% range with a median survival of 20 months. Adjuvant HAI after liver resection has shown an increase of hepatic disease-free survival and overall disease-free survival when compared to systemic therapy alone in three of four randomized trials. A recent update of the adjuvant trials after liver resection at Memorial Sloan Kettering Cancer Center has shown a 5-year survival of 78%.

CONCLUSION

HAI therapy has a role in treating hepatic metastases from CRC in both the resectable and unresectable setting.

Factors influencing recurrence following initial hepatectomy for colorectal liver metastases

BACKGROUND

Data on recurrence patterns following hepatectomy for colorectal liver metastases (CRLMs) and their impact on long-term outcomes are limited in the setting of modern multimodal management. This study sought to characterize the patterns of, factors associated with, and survival impact of recurrence following initial hepatectomy for CRLMs.

METHODS

A retrospective cohort study of patients undergoing initial hepatectomy for CRLMs at 39 institutions (2006-2013) was conducted. Kaplan-Meier methods were used for survival analyses. Overall survival landmark analysis at 12 months after hepatectomy was performed to compare groups based on recurrence. Multivariable Cox and regression models were used to determine factors associated with recurrence.

RESULTS

Among 2320 patients, tumours recurred in 47·4 per cent at median of 10·1 (range 0-88) months; 89·1 per cent of recurrences developed within 3 years. Recurrence was intrahepatic in 46·2 per cent, extrahepatic in 31·8 per cent and combined intra/extrahepatic in 22·0 per cent. The 5-year overall survival rate decreased from 74·3 (95 per cent c.i. 72·2 to 76·4) per cent without recurrence to 57·5 (55·0 to 60·0) per cent with recurrence (adjusted hazard ratio (HR) 3·08, 95 per cent c.i. 2·31 to 4·09). After adjusting for clinicopathological variables, prehepatectomy factors associated with increased risk of recurrence were node-positive primary tumour (HR 1·27, 1·09 to 1·49), more than three liver metastases (HR 1·27, 1·06 to 1·52) and largest metastasis greater than 4 cm (HR 1·19; 1·01 to 1·43).

CONCLUSION

Recurrence after CRLM resection remains common. Although overall survival is inferior with recurrence, excellent survival rates can still be achieved.

Outcomes after resection and/or radiofrequency ablation for recurrence after treatment of colorectal liver metastases

BACKGROUND

Repeat liver resection for colorectal liver metastases (CRLMs) is possible in a limited number of patients, with radiofrequency ablation (RFA) as an alternative for unresectable CRLMs. The aim of this study was to analyse survival rates with these interventions.

METHODS

This was a database analysis of patients who underwent first and repeat interventions for synchronous and metachronous CRLMs between 2000 and 2013. Descriptive and survival statistics were calculated.

RESULTS

Among 431 patients who underwent resection or RFA for CRLMs, 305 patients developed recurrences for which 160 repeat interventions (resection and/or RFA or ablative radiotherapy) were performed. In total, after 707 first or repeat interventions, 516 recurrences (73·0 per cent) developed, of which 276 were retreated curatively. At the time of first intervention, independent risk factors for death were lymph node-positive primary tumour (hazard ratio (HR) 1·40; P = 0·030), more than one CRLM (HR 1·53; P = 0·007), carcinoembryonic antigen level exceeding 200 ng/ml (HR 1·89; P = 0·020) and size of largest CRLM greater than 5 cm (HR 1·54; P = 0·014). The 5-year overall survival rates for liver resection and percutaneous RFA as first intervention were 51·9 and 53 per cent, with a median overall survival of 65·0 (95 per cent c.i. 47·3 to 82·6) and 62·1 (52·2 to 72·1) months, respectively.

CONCLUSION

RFA had good oncological outcomes in patients with unresectable CRLMs. Radiofrequency ablation is progressively more applied with each additional intervention.

Schisandra sphenanthera Extract Facilitates Liver Regeneration after Partial Hepatectomy in Mice

Liver regeneration after surgical liver resection is crucial for the restoration of liver mass and the recovery of liver function.Schisandra sphenanthera extract (Wuzhi tablet, WZ) is a preparation of an extract from the dried ripe fruit of Schisandra sphenanthera Rehd. et Wils, a traditional hepatoprotective herb. Previously, we found that WZ could induce liver regeneration-related genes against acetaminophen-induced liver injury. However, whether WZ can directly facilitate liver regeneration after liver resection remains unknown. We investigated whether WZ has potential in promoting liver regeneration after a partial hepatectomy (PHX) in mice. Remnant livers were collected 1, 1.5, 2, 3, 5, 7, and 10 days after PHX. Hepatocyte proliferation was assessed using the Ki-67 labeling index. Western blot analysis was performed on proteins known to be involved in liver regeneration. The results demonstrated that WZ significantly increased the liver-to-body weight ratio of mice after PHX but had no effect on that of mice after a sham operation. Additionally, the peak hepatocyte proliferation was observed at 1.5 days in PHX/WZ-treated mice but at 2 days in PHX/saline-treated mice, as evidenced by the Ki-67 positive ratio. Furthermore, WZ significantly increased the protein expression of ligand-induced phosphorylation of epidermal growth factor receptor and up-regulated cyclin D1, cyclin D-dependent kinase 4, phosphorylated retinoblastoma, and proliferating cell nuclear antigen protein expression and down-regulated the expression of cell cycle inhibitors p21 and p27 in the regenerative process after PHX. These results demonstrate that WZ significantly facilitates hepatocyte proliferation and liver regeneration after PHX.

Safety and Efficacy of Ultrasound-Guided Radiofrequency Ablation of Recurrent Colorectal Cancer Liver Metastases after Hepatectomy

INTRODUCTION

To assess the results and outcome of radiofrequency ablation in the treatment of recurrent colorectal liver metastases.

PATIENTS AND METHODS

Between January 2005 and September 2012, we treated 59 patients with recurrent colorectal metastases not amenable to surgery with 77 radiofrequency ablation procedures. Radiofrequency was indicated if oncologic resection was technically not possible or the patient was not fit for major surgery. A total of 91 lesions were treated. The mean number of liver tumors per patient was 1.5, and the mean tumor diameter was 2.3 cm. In 37.5% of the cases, lesions had a subcapsular location, and 34% were close to a vascular structure.

RESULTS

The morbidity rate was 18.7%, and there were no post-procedural deaths. Distant extrahepatic recurrence appeared in 50% of the patients. Local recurrence at the site of ablation appeared in 18% of the lesions. Local recurrence rate was 6% in lesions less than 3 cm and 52% in lesions larger than 3 cm. The size of the lesions (more than 3 cm) was an independent risk factor for local recurrence (p < 0.05). Survival rates at 1, 3, and 5 years were 94.5%, 65.3%, and 21.7%, respectively.

DISCUSSION

Radiofrequency ablation is a safe procedure and allows local tumor control in lesions less than 30 mm (local recurrence of 6%) and provides survival benefits in patients with recurrent colorectal liver metastases.

Colorectal cancer liver metastases: long-term survival and progression-free survival after thermal ablation using magnetic resonance-guided laser-induced interstitial thermotherapy in 594 patients: analysis of prognostic factors

PURPOSE

The purpose of this study was the evaluation of prognostic factors for long-term survival and progression-free survival (PFS) after treatment of colorectal cancer (CRC) liver metastases with magnetic resonance-guided laser-induced interstital thermotherapy (LITT).

PATIENTS AND METHODS

We included 594 patients (mean age, 61.2 years) with CRC liver metastases who were treated with LITT. The statistical analysis of the long-term survival and PFS were based on the Kaplan-Meier method. The Cox regression model tested different parameters that could be of prognostic value. The tested prognostic factors were the following: sex, age, the location of primary tumor, the number of metastases, the maximal diameter and total volume of metastases and necroses, the quotient of total volumes of metastases and necroses, the time of appearance of liver metastases and location in the liver, the TNM classification of CRC, extrahepatic metastases, and neoadjuvant treatments.

RESULTS

The median survival was 25 months starting from the date of the first LITT. The 1-, 2-, 3-, 4-, and 5-year survival rates were 78%, 50.1%, 28%, 16.4%, and 7.8%, respectively. The median PFS was 13 months. The 1-, 2-, 3-, 4-, and 5-year PFS rates were 51.3%, 35.4%, 30.7%, 25.4%, and 22.3%, respectively. The number of metastases and their maximal diameter were the most important prognostic factors for both long-term survival and PFS. Long-term survival was also highly influenced by the initial involvement of the lymph nodes.

CONCLUSIONS

For patients treated with LITT for CRC liver metastases, the number and size of metastases, together with the initial lymph node status, are significant prognostic factors for long-term survival.

Patterns of recurrence after liver transplantation for nonresectable liver metastases from colorectal cancer

Background

Surgical resection is the only curative modality for colorectal liver metastases (CLM), and the pattern of recurrences after resection affects survival. In a prospective study of liver transplantation (Lt) for nonresectable CLM we have shown a 5-year overall survival rate of 60 %, but 19 of 21 experienced recurrence. This study reports the pattern of recurrences after Lt for CLM and the effect on survival.

Methods

Characterization of metastatic lesions in a prospective study for Lt for nonresectable CLM was performed (n = 21). The study included reexamination of chest computed tomographic scans taken before Lt.

Results

At the time of first recurrence, 16 were a single site, and three were multiple sites. Thirteen of the single sites were pulmonary recurrences. The pulmonary recurrences appeared early and were slow growing, and several were accessible to surgical treatment. When chest computed tomographic scans were reexamined, seven patients had pulmonary nodules at the time of Lt without an effect on survival. There was no first single-site hepatic recurrence. Six of the seven patients who developed metastases to the transplanted liver died from metastatic disease.

Conclusions

The pulmonary recurrences after Lt for CLM were of an indolent character, even those that were present at the time of Lt. This contrasts with the finding of metastases to the transplanted liver, which was prognostically adverse. The lack of single hepatic first-site recurrences and hepatic metastases only as part of disseminated disease is different from the pattern of recurrence after liver resection. This suggests two distinct mechanisms for hepatic recurrences after resection for CLM.

Prognostic significance of early recurrence: a conditional survival analysis in patients with resected colorectal liver metastasis

BACKGROUND

For patients undergoing liver resection for colorectal metastases, specific clinico-pathological variables have been shown to be prognostic at baseline. This study analyses how the prognostic capability of these variables changes in a conditional survival model.

METHODS

Retrospective review of a prospectively maintained database of patients who underwent an R0 resection of colorectal liver metastases from 1994 to 2004 at a single institution.

RESULTS

In total, 807 patients were identified, with an 87-month median follow-up for survivors. Five- and 10-year disease-specific survivals (DSS) were 68% and 55%, respectively. The probability of further survival increased as the survival time increased. For 3-year survivors (n = 504), DSS were no longer significantly different between patients with a low (0-2) or high (3-5) clinical risk score (CRS, P = 0.19). On multivariate analysis, independent predictors of DSS for 3-year survivors were recurrence within the first 3 years after a liver resection, a pre-operative carcinoembryonic antigen (CEA) >200 ng/ml and disease-free interval <12 months prior to the diagnosis of liver metastasis. However, for those patients who were recurrence free at 1 year, no clinico-pathological variables retained prognostic significance.

DISCUSSION

After 3 years of DSS and 1 year of recurrence-free survival, baseline clinico-pathological variables have a limited ability to predict future survival. Early post-operative recurrence appears to be the most useful single clinical feature in estimating conditional DSS.

Adjuvant chemotherapy with or without pelvic radiotherapy after simultaneous surgical resection of rectal cancer with liver metastases: analysis of prognosis and patterns of recurrence

PURPOSE

To investigate the outcomes of adjuvant chemotherapy (CT) or chemoradiotherapy (CRT) after simultaneous surgical resection in rectal cancer patients with liver metastases (LM).

MATERIALS AND METHODS

One hundred and eight patients receiving total mesorectal excision for rectal cancer and surgical resection for LM were reviewed. Forty-eight patients received adjuvant CRT, and 60 were administered CT alone. Recurrence patterns and prognosis were analyzed. Disease-free survival (DFS) and overall survival (OS) rates were compared between the CRT and CT groups. The inverse probability of the treatment-weighted (IPTW) method based on the propensity score was used to adjust for selection bias between the two groups.

RESULTS

At a median follow-up period of 47.7 months, 77 (71.3%) patients had developed recurrences. The majority of recurrences (68.8%) occurred in distant organs. By contrast, the local recurrence rate was only 4.7%. Median DFS and OS were not significantly different between the CRT and CT groups. After applying the IPTW method, we observed no significant differences in terms of DFS (hazard ratio [HR], 1.347; 95% confidence interval [CI], 0.759-2.392; p = 0.309) and OS (HR, 1.413; CI, 0.752-2.653; p = 0.282). Multivariate analyses showed that unilobar distribution of LM and normal preoperative carcinoembryonic antigen level (<6 mg/mL) were significantly associated with longer DFS and OS.

CONCLUSIONS

The local recurrence rate after simultaneous resection of rectal cancer with LM was relatively low. DFS and OS rates were not different between the adjuvant CRT and CT groups. Adjuvant CRT may have a limited role in this setting. Further prospective randomized studies are required to evaluate optimal adjuvant treatment in these patients.

Systematic review and meta-analysis of follow-up after hepatectomy for colorectal liver metastases2

Background

The evidence surrounding optimal follow-up after liver resection for colorectal metastases remains unclear. A significant proportion of recurrences occur in the early postoperative period, and some groups advocate more intensive review at this time.

Methods

A systematic review of literature published between January 2003 and May 2010 was performed. Studies that described potentially curative primary resection of colorectal liver metastases that involved a defined follow-up protocol and long-term survival data were included. For meta-analysis, studies were grouped into intensive (more frequent review in the first 5 years after resection) and uniform (same throughout) follow-up.

Results

Thirty-five studies were identified that met the inclusion criteria, involving 7330 patients. Only five specifically addressed follow-up. Patients undergoing intensive early follow-up had a median survival of 39·8 (95 per cent confidence interval 34·3 to 45·3) months with a 5-year overall survival rate of 41·9 (34·4 to 49·4) per cent. Patients undergoing routine follow-up had a median survival of 40·2 (33·4 to 47·0) months, with a 5-year overall survival rate of 38·4 (32·6 to 44·3) months.

Conclusion

Evidence regarding follow-up after liver resection is poor. Meta-analysis failed to identify a survival advantage for intensive early follow-up.

Regulation of signal transduction and role of platelets in liver regeneration

Among all organs, the liver has a unique regeneration capability after sustaining injury or the loss of tissue that occurs mainly due to mitosis in the hepatocytes that are quiescent under normal conditions. Liver regeneration is induced through a cascade of various cytokines and growth factors, such as, tumor necrosis factor alpha, interleukin-6, hepatocyte growth factor, and insulin-like growth factor, which activate nuclear factor κB, signal transducer and activator of transcription 3, and phosphatidyl inositol 3-kinase signaling pathways. We previously reported that platelets can play important roles in liver regeneration through a direct effect on hepatocytes and collaborative effects with the nonparenchymal cells of the liver, including Kupffer cells and liver sinusoidal endothelial cells, which participate in liver regeneration through the production of various growth factors and cytokines. In this paper, the roles of platelets and nonparenchymal cells in liver regeneration, including the associated cytokines, growth factors, and signaling pathways, are described.

The intraportal injection model for liver metastasis: advantages of associated bioluminescence to assess tumor growth and influences on tumor uptake of radiolabeled anti-carcinoembryonic antigen antibody

BACKGROUND

Radioimmunotherapy is emerging as a new tool for adjuvant therapy of colorectal cancer. The liver remains the main site for metastases, carrying a high mortality rate. Many animal models are available but none associates easy, reliable implantation and in-vivo follow-up for experimental therapeutic studies. The aims of this study were to develop a reliable hepatic metastatic colonic cancer model in mice using the intraportal route for injection, with follow-up by bioluminescence (BLI) and to evaluate the impact of tumor location on tumor antigen direct targeting using radiolabeled anti-CEA (carcinoembryonic antigen) antibodies.

METHODS

Ls-174T Luc+ is a colon carcinoma cell line strongly expressing CEA, transfected with the luciferase gene for BLI. Isolated or aggregated cells (1×10(6)) were injected through the portal vein. The tumor burden was investigated using BLI to assess hepatic implantation and growth kinetics. The biodistribution of the 125I anti-CEA antibody fragment (F6) was studied in this model and was compared with subcutaneous implantation.

RESULTS

The tumor implantation rate was 100% using aggregated cells compared with 26.6% of isolated cells. Photons emitted by 1×10(6) cells were detected by BLI immediately after injection and allowed visual confirmation of hepatic distribution. The tumor growth was assessed over time to select homogeneous groups of animals. Radiolabeled anti-CEA antibody biodistributions showed a significantly higher uptake in hepatic than in subcutaneous tumors.

CONCLUSION

The association of hepatic tumor graft through the portal route and BLI provides a reliable animal model and permits sensitive in-vivo detection and follow-up of hepatic metastases. The hepatic model seems to more closely reproduce colon cancer metastases compared with subcutaneous metastasis. The hepatic model is of particular interest for studying radioimmunotherapy.

Risk factors for early recurrence after curative hepatectomy for colorectal liver metastases

PURPOSE

With the broadening indications for hepatectomy to treat colorectal liver metastases (CRLM), early recurrence is a major problem. The aim of this study is to identify risk factors of early recurrence, defined as recurrence within 1 year after surgery.

METHODS

A retrospective analysis was performed on 121 consecutive patients who underwent hepatectomy for CRLM.

RESULTS

Among 121 patients, 52 (43.0%) developed early recurrence. The independent risk factor for early recurrence was "number of liver metastases ≥ 3" (odds ratio 2.65). There were significantly more patients with liver recurrence (51.9%) and recurrence beyond curative surgical resection (63.5%) in those with early recurrence. In addition, patients with three or more liver metastases had significantly more liver recurrence (66.7%; P = 0.02) and recurrence beyond curative surgical resection (70.8%; P = 0.04). The overall survival rates of both patients with early recurrence (5-year survival rate 20%) and those with three or more liver metastases (5-year survival rate 24%) were significantly worse.

CONCLUSIONS

The independent risk factor for early recurrence is the "number of liver metastases ≥ 3." Patients with three or more liver metastases have a significantly higher risk of liver recurrence and a higher rate of recurrence beyond curative surgical resection, and these are correlated with a poor prognosis.

Role of intra-arterial hepatic chemotherapy in the treatment of colorectal cancer metastases

Hepatic metastases are common with colorectal cancer. The primary blood supply to hepatic metastases is the hepatic artery. Regional chemotherapy utilizing the hepatic artery is one treatment option for liver metastases. The advantage of hepatic arterial chemotherapy is that high concentrations of the therapeutic drug are obtained in the liver with minimal systemic toxicity. Recently, systemic chemotherapy regimens have been added to hepatic arterial infusional chemotherapy to treat hepatic metastases. Due to the high response rates in the liver, resection rates are increasing in patients originally thought to have unresectable liver disease. Hepatic arterial chemotherapy has also been used in the adjuvant setting after resection of all liver metastases in order to minimize hepatic recurrences. The role of hepatic arterial infusional therapy in treating hepatic colorectal metastases includes treating patients with both resectable and unresectable metastases in the adjuvant, neoadjuvant, or palliative settings.

Added value of positron emission tomography imaging in the surgical treatment of colorectal liver metastases

OBJECTIVE

[F-18]-Fluorodeoxyglucose-positron emission tomography (FDG-PET) is used increasingly in the work-up to surgery for patients with potentially resectable colorectal liver metastases. This study evaluates the clinical effectiveness, impact on health care resources and cost-effectiveness of adding FDG-PET to the diagnostic algorithm alongside a randomized clinical trial from a health care perspective.

METHODS

In a randomized clinical trial, the net monetary benefit (NMB) of FDG-PET added to conventional diagnostic work-up (CWU) was determined in patients with colorectal liver metastases. Seventy-five patients were included in each arm. Change in clinical management, futile laparotomies, preoperative findings and all relevant health care consumption were prospectively documented during 3 years. To assess health-related quality of life European Quality of Life-5 Dimensions was administered at the time of randomization, 3 and 6 weeks postoperatively, and every 3 months postoperatively for 3 years. Quality-adjusted life years (QALYs) were calculated based on European Quality of Life-5 Dimensions outcomes.

RESULTS

In adding FDG-PET, diagnostic performance increased and futile laparotomies were reduced by 38%. Both health-related quality of life and QALYs showed no significant difference between the CWU and PET groups. For CWU and PET groups costs were euro 92,836 and euro 81,776, respectively, accumulated in 3 years after randomization. NMB ranged from euro 1004 to euro 11,060 depending on the monetary value given to a QALY. When costs for chemotherapy were disregarded, costs amounted to euro 15,874 for CWU and euro 18,664 for PET group.

CONCLUSION

Additional costs of FDG-PET in the diagnostic work-up of patients with potentially resectable colorectal liver metastases were compensated by a reduction in futile laparotomies. The NMB analysis showed savings over a relevant range of willingness to pay for a QALY.

p66(Shc) has a pivotal function in impaired liver regeneration in aged mice by a redox-dependent mechanism

Liver regeneration involves complicated processes and is affected by various patho-physiological conditions. This study was designed to examine the molecular mechanisms underlying the aging-associated impairment of liver regeneration. Male C57BL/6J mice were used as young and aged mice (<10 weeks and >20 months old, respectively). These mice were subjected to 70% partial hepatectomy (PH). Liver regeneration and liver injury/stresses were evaluated chronologically after PH. Post-hepatectomy liver regeneration was markedly impaired in aged mice. Though the extent of hepatocyte proliferation in the regenerating liver was similar in aged and young mice, cell growth was absent in aged mice. Oxidative stress (OS) was observed immediately after hepatectomy, followed by marked apoptosis in aged mice. Signaling molecules regarding cell proliferation (mitogen-activated protein kinase, STAT3, p46/52(Shc)) and anti-oxidation (catalase, superoxide dismutase, Ref-1, glutathione peroxidase) were expressed/activated after hepatectomy in livers of both aged and young mice. Akt was not activated in aged-mouse liver, but its expression was similar to that in young mice. p66(Shc), known as an age-/oxidant-associated protein, was strongly phosphorylated. By knocking down p66(Shc), the impairment of liver regeneration was normalized. OS immediately after hepatectomy induced subsequent liver injury (apoptosis), and deletion of p66(Shc) suppressed both OS and hepatocyte apoptosis in the regenerating liver of aged mice. Though we need additional data in other animal models to fully understand the mechanism, p66(Shc) may have a pivotal function in the impairment of liver regeneration in aged mice by triggering OS and subsequent apoptosis. This data may provide a clue to understanding the mechanism underlying the association between aging and the impairment of liver regeneration.

Effect on outcome of recurrence patterns after hepatectomy for colorectal metastases

BACKGROUND

Despite improvements in surgery and chemotherapy, most patients develop recurrence after hepatectomy for metastatic colorectal cancer. Data are lacking on the effect of these patterns on outcome.

METHODS

A retrospective review of a prospectively maintained hepatobiliary database was performed. Pattern and timing of recurrence and outcome after recurrence were analyzed. Univariate and multivariate analyses of factors associated with outcome after recurrence were carried out.

RESULTS

From January 1997 through May 2003, a total of 733 patients underwent hepatectomy for colorectal metastases. Of these, 637 patients (87%) were included in the analysis, and in 393 patients (62%), recurrence was documented at the time of last follow-up. Initial recurrence patterns included the following: liver only in 120 patients (31%), lung only in 107 (27%), other single sites in 49 (12%), and multiple sites in 117 (30%). Recurrence occurred within 2 years of hepatectomy in 75% of patients and after 3 years in 11%. Margins at hepatectomy, recurrence pattern, resected recurrence, and disease-free interval from time of colectomy to hepatic metastasis and from time of hepatectomy to recurrence were independently associated with survival as measured from the time of recurrence. Recurrence in the lung, resected recurrence, and time to recurrence after hepatectomy were associated with prolonged survival as measured from the time of hepatectomy and the time of recurrence.

CONCLUSIONS

The timing and pattern of recurrence after hepatic resection for metastatic colorectal cancer are important predictors of long-term survival.

Activation of human liver sinusoidal endothelial cell by human platelets induces hepatocyte proliferation

BACKGROUND & AIMS

We previously reported that platelets promote hepatocyte proliferation. In this study, we focused on the role of platelets in liver sinusoidal endothelial cells (LSECs) in addition to their role in hepatocyte in liver regeneration.

METHODS

Immortalized human LSECs (TMNK-1) were used. The LSECs were co-cultured with human platelets, and the proliferation of LSECs and the excretion of growth factors and interleukin-6 (IL-6) were subsequently measured. The main factor from platelets which induced the excretion of IL-6 from LSECs was determined using inhibitors of each component contained in the platelets. The need for direct contact between platelets and LSECs was investigated using cell culture inserts. The proliferation of human primary hepatocytes was measured after the addition of the supernatant of LSECs cultured with or without platelets.

RESULTS

The number of LSECs cocultured with platelets significantly increased. Excretion of IL-6 and vascular endothelial growth factor (VEGF) increased in LSECs with platelets. JTE-013, a specific antagonist for sphingosine 1-phosphate (S1P) 2 receptors, inhibited the excretion of IL-6 from LSECs after the addition of platelets. When the platelets and LSECs were separated by the cell culture insert, the excretion of IL-6 from LSECs was decreased. DNA synthesis was significantly increased in human primary hepatocytes cultured with the supernatant of LSECs with platelets.

CONCLUSIONS

Platelets promote LSEC proliferation and induce IL-6 and VEGF production. Direct contact between the platelets and LSECs and S1P, that are contained in platelets, were involved in the excretion of IL-6 from LSECs. IL-6 from LSECs induced proliferation of parenchymal hepatocytes.

Outcomes of intensive surveillance after resection of hepatic colorectal metastases

BACKGROUND

The impact of computed tomography (CT)-based follow-up for the detection of resectable disease recurrence following surgery for colorectal liver metastases (CRLM) was evaluated.

METHODS

Some 705 patients undergoing resection of CRLM between January 1993 and March 2007 were included. Surveillance comprised 3-monthly CT (thorax, abdomen and pelvis) in the first 2 years after surgery, 6 monthly for 3 years and annually from years 6 to 10. Survival differences following recurrence between patients managed surgically and palliatively were determined, and the cost was calculated.

RESULTS

Five-year disease-free and overall survival rates were 28.3 and 32.3 per cent respectively. Of 402 patients who developed recurrence within 2 years, 88 were treated with liver resection alone and 36 with lung and/or liver resection. Their 5-year overall survival rates were 31 and 30 per cent respectively, compared with 3.9 per cent in 278 patients managed palliatively (P < 0.001). For each 3-month interval during the first year of follow-up, patients with recurrence treated surgically had better overall survival than those treated palliatively. The cost of surveillance that identified 124 patients amenable to further resection was 12,338 pounds per operated recurrence. Assuming that patients with recurrence gained 5 years' survival, the mean survival gain was 4.28 years per resection and the cost per life-year gained was 2883 pounds.

CONCLUSION

Intensive 3-monthly CT surveillance after liver resection for CRLM detects recurrence that is amenable to further resection in a considerable number of patients. These patients have significantly better survival with a reasonable cost per life-year gained.

Regional hepatic chemotherapies in treatment of colorectal cancer metastases to the liver

Colorectal cancer metastases to the liver are primarily supplied by the hepatic artery. Therefore, delivery of regional chemotherapy via the hepatic artery is a viable treatment option. Chemotherapy can be delivered in high concentration to the liver with minimal systemic toxicity. Hepatic artery infusional (HAI) chemotherapy both alone and in combination with systemic chemotherapy in the treatment of isolated hepatic metastases from colorectal cancer has resulted in high response rates and increased resection rates for previously unresectable liver disease. Regional chemotherapy can also be used as adjuvant treatment after complete resection of liver metastases to reduce hepatic recurrences. The combination of HAI therapy with modern systemic chemotherapy has a role in the palliative, adjuvant, and neoadjuvant settings.

Patterns of recurrence after curative-intent radiation for oligometastases confined to one organ

OBJECTIVES

We sought to characterize and describe the patterns of distant recurrence in patients with macroscopic oligometastases, limited in number (<or=5) and confined to one organ, treated with curative-intent stereotactic body radiotherapy (SBRT).

METHODS

Seventy-seven patients enrolled on prospective studies of SBRT for oligometastases are included in the present analysis. All available radiography and records were retrospectively reviewed to determine the timing and location of recurrences.

RESULTS

New metastases occurred in 73% of patients. Among these patients, new metastases developed most frequently in the same organ (occurring in 82% of first new metastases after SBRT and 89% of cumulative new metastases). Metastases to other organs were common as well (occurring cumulatively in 79% of patients). In patients with liver oligometastases, common sites of further progression included the liver, other abdominal organs, and lungs. In patients with lung oligometastases, common sites of further progression included the lungs, thoracic lymph nodes, bones, liver, and brain.

CONCLUSIONS

Patients receiving SBRT for oligometastases confined to one organ are apt to develop new metastases, most frequently occurring in the initially involved organ, but also commonly in other organs. A subset of patients remains disease free after extended follow-up.

Alternating systemic and hepatic artery infusion therapy for resected liver metastases from colorectal cancer: a North Central Cancer Treatment Group (NCCTG)/ National Surgical Adjuvant Breast and Bowel Project (NSABP) phase II intergroup trial, N9945/CI-66

PURPOSE Prior trials have shown that surgery followed by hepatic artery infusion (HAI) of floxuridine (FUDR) alternating with systemic fluorouracil improves survival rates. Oxaliplatin combined with capecitabine has demonstrated activity in advanced colorectal cancer. Based on this observation a trial was conducted to assess the potential benefit of systemic oxaliplatin and capecitabine alternating with HAI of FUDR. The primary end point was 2-year survival. PATIENTS AND METHODS Patients with liver-only metastases from colorectal cancer amenable to resection or cryoablation were eligible. HAI and systemic therapy was initiated after metastasectomy. Alternating courses of HAI consisted of 0.2 mg/m(2)/d FUDR and dexamethasone, day 1 through 14 weeks 1 and 2. Systemic therapy included oxaliplatin 130 mg/m(2) day 1 with capecitabine at 1,000 mg/m(2) twice daily, days 1 through 14, weeks 4 and 5. Two additional 3-week courses of systemic therapy were given. Capecitabine was reduced to 850 mg/m(2) twice daily after interim review of toxicity. Results Fifty-five of 76 eligible patients were able to initiate protocol-directed therapy and completed median of six cycles (range, one to six). Three postoperative or treatment-related deaths were reported. Overall, 88% of evaluable patients were alive at 2 years. With a median follow-up of 4.8 years, a total of 30 patients have had disease recurrence, 11 involving the liver. Median disease-free survival was 32.7 months. CONCLUSION Alternating HAI of FUDR and systemic capecitabine and oxaliplatin met the prespecified end point of higher than 85% survival at 2 years and was clinically tolerable. However, the merits of this approach need to be established with a phase III trial.

Improved selection of patients for hepatic surgery of colorectal liver metastases with (18)F-FDG PET: a randomized study

With the increasing possibilities for surgical treatment of colorectal liver metastases, careful selection of patients who may benefit from surgical treatment becomes critical. The addition of PET to (18)F-FDG may significantly improve conventional staging by CT. Up to now, definitive evidence that the addition of (18)F-FDG PET to conventional staging leads to superior clinical results and improved clinical management in these patients has been lacking. In this randomized controlled trial in patients with colorectal liver metastases, we investigated whether the addition of (18)F-FDG PET is beneficial and reduces the number of futile laparotomies.

METHODS

A total of 150 patients with colorectal liver metastases selected for surgical treatment by imaging with CT were randomly assigned to CT only (n = 75) or CT plus (18)F-FDG PET (n = 75). Patients were followed up for at least 3 y. The primary outcome measure was futile laparotomy, defined as any laparotomy that did not result in complete tumor treatment, that revealed benign disease, or that did not result in a disease-free survival period longer than 6 mo.

RESULTS

Patient and tumor characteristics were similar for both groups. The number of futile laparotomies was 34 (45%) in the control arm without (18)F-FDG PET and 21 (28%) in the experimental arm with (18)F-FDG PET; the relative risk reduction was 38% (95% confidence interval, 4%-60%, P = 0.042).

CONCLUSION

The number of futile laparotomies was reduced from 45% to 28%; thus, the addition of (18)F-FDG PET to the work-up for surgical resection of colorectal liver metastases prevents unnecessary surgery in 1 of 6 patients.

The role of floxuridine in metastatic liver disease

Liver metastases are mainly supplied by the hepatic artery. Sustained high levels of intratumoral drug are achievable with certain drugs given via the hepatic artery. Floxuridine (FUDR) is an ideal drug for hepatic arterial infusion (HAI) due to its short half life, steep dose response curve, high total body clearance, and high hepatic extraction. HAI FUDR has consistently shown higher response rates than systemic chemotherapy alone, and some studies have shown a survival advantage. HAI FUDR in combination with systemic chemotherapy has evolved over the years and may be used in palliative, neoadjuvant, and adjuvant settings. The dramatic responses observed with HAI FUDR plus modern era systemic chemotherapy offer the possibility of resection and cure in selected patients. The high hepatic extraction of FUDR limits systemic side effects. Toxicity includes biliary and gastrointestinal ulcers.

The survival pathways phosphatidylinositol-3 kinase (PI3-K)/phosphoinositide-dependent protein kinase 1 (PDK1)/Akt modulate liver regeneration through hepatocyte size rather than proliferation

Liver regeneration comprises a series of complicated processes. The current study was designed to investigate the roles of phosphoinositide-dependent protein kinase 1 (PDK1)-associated pathways in liver regeneration after partial hepatectomy (PH) using liver-specific Pdk1-knockout (L-Pdk1KO) and Pdk1/STAT3 double KO (L-DKO) mice. There was no liver regeneration, and 70% PH was lethal in L-Pdk1KO mice. Liver regeneration was severely impaired equally in L-Pdk1KO and L-DKO mice, even after nonlethal 30% PH. There was no cell growth (measured as increase of cell size) after hepatectomy in L-Pdk1KO mice, although the post-PH mitotic response was the same as in controls. As expected, hepatectomy did not induce hepatic Akt-phosphorylation (Thr308) in L-Pdk1KO mice, and post-PH phosphorylation of Akt, mammalian target of rapamycin (mTOR), p70 ribosomal S6 kinase (p70(S6K)), and S6 were also reduced. To examine the specific role of PDK1-associated signals, a "pif-pocket" mutant of PDK1, which allows PDK1 only to phosphorylate Akt, was used. Liver regeneration was recovered in L-Pdk1KO mice with a "pif-pocket" mutant of PDK1. This re-activated Akt in L-Pdk1KO mice liver and induced post-PH cell growth, without affecting cell proliferation. Further deletion of STAT3 (L-DKO mice) did not further deteriorate liver regeneration, although this certainly reduced post-PH mitotic response. These findings indicate that PDK1/Akt contribute to liver regeneration by regulating cell size. Regarding phosphatidylinositol-3 kinase (PI3-K), immediate upstream signal of PDK1, activation of PI3-K induced cell proliferation via STAT3 activation in the liver of L-Pdk1KO mice but did not improve impaired liver regeneration. This confirmed the pivotal role of PDK1 in liver regeneration and cell growth.

CONCLUSION

PDK1/Akt-mediated responsive cell growth is essential for normal liver regeneration after PH, especially when cell proliferation is impaired.

Critical questions in the imaging of colorectal hepatic metastases

Aggressive treatment of patients with colorectal liver metastases can improve treatment outcome. In this paper, we review current management of patients with colorectal liver metastases and discuss the critical questions that the radiologist should consider when reviewing the imaging of these patients, so as to provide information that is important for formulating treatment strategies by the multidisciplinary management team.

Autonomic regulation of liver regeneration after partial hepatectomy in mice

BACKGROUND/AIMS

The autonomic vagus nerve is thought to play an essential role in liver regeneration since hepatic vagotomy delays hepatic DNA synthesis. However, how the parasympathetic vagus nerve is involved in liver regeneration remains obscure. Kupffer cells are located in liver sinusoids adjacent to hepatocytes and might regulate liver regeneration by releasing interleukin-6 (IL-6). The present study examines the role of the vagus nerve and how Kupffer cells are involved in parasympathetic nerve-mediated liver regeneration in mice.

METHODS

We performed surgical vagotomy of the hepatic branch and then partial hepatectomy (PH); some mice received acetylcholine (ACh) agonist/antagonist before PH. We then evaluated liver regeneration and signal transducer and activator of transcription-3 (STAT3) activation. We also investigated whether ACh stimulates IL-6 release from Kupffer cells.

RESULTS

Surgical vagotomy impaired liver regeneration. STAT3, which is activated by IL-6 after hepatectomy and plays a pivotal role in liver regeneration, was less activated in vagotomized mice after PH. Post-PH STAT3 activation was recovered by administering vagotomized mice with an ACh agonist. Furthermore, ACh stimulated IL-6 release in Kupffer cells in vitro.

CONCLUSION

The parasympathetic system (vagus nerve) contributes to liver regeneration after hepatectomy by stimulating IL-6 release from Kupffer cells followed by STAT3 activation in hepatocytes.

The role of FDG-PET in the selection of patients with colorectal liver metastases

BACKGROUND

Selection of patients for hepatic resection of colorectal liver metastases is still limited. After conventional work up by computed tomography (CT) scan, 60% of patients will develop recurrent disease in the early years after resection. The aim of the present study was to evaluate whether an additional fluorine-18-deoxyglucose positron emission tomography (FDG-PET) improves patient selection and therefore adds value to select patients for curative liver resection.

METHODS

Data from 203 patients selected for surgical treatment of colorectal liver metastases between 1995 and 2003 were collected in a prospective database. Group A consisted of 100 consecutive patients selected for hepatic surgery by conventional diagnostic imaging (CT chest and abdomen) only. Group B consisted of 103 consecutive patients selected for hepatic surgery by conventional diagnostic methods plus an additional FDG-PET.

RESULTS

The number of patients with futile surgery, in which further treatment was considered inappropriate at laparotomy, was 28.0% in group A and 19.4% in group B. The reason for unresectable disease differed between groups. In group A, 10/100 (10.0%) patients showed extrahepatic abdominal disease versus 2/103 patients (1.9%) in group B (P = .017). In all other cases, resection was not performed because liver disease proved too extensive at laparotomy. For patients ultimately undergoing surgical treatment of the metastases, survival was comparable between groups. Overall survival at 3 years was 57.1% in group A versus 60.1% in group B. Disease-free survival at 3 years was 23.0% in group A and 31.4% in group B.

CONCLUSIONS

In patients with colorectal liver metastases, FDG-PET may reduce the number of negative laparotomies. However, the effect size on the selection of these patients seems not sufficient enough to affect the overall and disease-free survival after treatment.

Surgical approaches of resectable synchronous colorectal liver metastases: Timing considerations

AIM: To compare the safety and efficacy of simultaneous versus two stage resection of primary colorectal tumors and liver metastases.

METHODS: From January 1996 to May 2004, 103 colorectal tumor patients presented with synchronous liver metastases. Twenty five underwent simultaneous colorectal and liver surgery and 78 underwent liver surgery 1-3 mo after primary colorectal tumor resection. Data were retrospectively analyzed to assess and compare the morbidity and mortality between the surgical strategies. The two groups were comparable regarding the age and sex distribution, the types of liver resection and stage of primary tumors, as well as the number and size of liver metastases.

RESULTS: In two-stage procedures more transfusions were required (4 ± 1.5 vs 2 ± 1.8, pRBCs, P < 0.05). Chest infection was increased after the two-stage approach (26% vs 17%, P < 0.05). The two-stage procedure was also associated with longer hospitalization (20 ± 8 vs 12 ± 6 d, P < 0.05). Five year survival in both groups was similar (28% vs 31%). No hospital mortality occurred in our series.

CONCLUSION: Synchronous colorectal liver metastases can be safely treated simultaneously with the primary tumor. Liver resection should be prioritized over colon resection. It is advisable that complex liver resections with marginal liver residual volume should be dealt with at a later stage.

Laparoscopic liver resection using radiofrequency coagulation

BACKGROUND

The use of radiofrequency (RF) energy has been described to perform open liver resection safely and with minimal blood loss. Yet no data are available on the potential contribution of RF energy to the limitation of intraoperative blood loss during laparoscopic liver resection (LLR). The aim of this prospective, nonrandomized study was to investigate the potential contribution of RF energy to the limitation of intraoperative blood loss in patients undergoing LLR.

METHODS

Forty-five patients [male/female ratio 22/23, age 57 years (26-80)] underwent LLR. Eleven benign and 47 malignant lesions (mostly colorectal metastases) were resected. Median number [1 (1-3)] and maximum diameter [40 mm (8-170)] of tumors as well as median tumor free margins [10 mm (1-30)] were comparable in patients undergoing LLR with (20 patients) or without (25 patients) RF-assistance. Thirty-eight minor (< or = 2 segments) and 9 major (> 3 segments) resections were performed. Eighteen patients simultaneously underwent additional surgery.

RESULTS

No mortality occurred. Median intraoperative blood loss was 200 (5-4000) ml and was similar in patients undergoing LLR with or without RF-assistance. The type of surgical procedure was a determinant for the amount of intraoperative blood loss (p = 0.0002). Significant bleeding occurred from large hepatic vessels at major resections. Median operation time was 115 (45-360) minutes. RF-assistance didn't seem to reduce perioperative morbidity.

CONCLUSIONS

LLR can be performed with minimal intraoperative blood loss, which is determined by the type of hepatectomy. Significant intraoperative bleeding occurs from large hepatic vessels during major resections. RF-assisted parenchymal transection in LLR doesn't seem to reduce blood loss, operation time, or perioperative morbidity.

Evolving techniques in the treatment of liver colorectal metastases: role of laparoscopy, radiofrequency ablation, microwave coagulation, hepatic arterial chemotherapy, indications and contraindications for resection, role of transplantation, and timing of chemotherapy

The management of patients who have hepatic metastases from CRC has become increasingly complex as the number of modalities that is available to treat these tumors has increased. Surgical resection remains the mainstay of treatment, when possible, and may become an option in an increasing proportion of patients that has advanced disease and previously were considered unresectable when treated with a combination of neoadjuvant systemic or hepatic arterial chemotherapy. The role of microwave coagulation and RFA can be considered only complementary to surgical resection at this point, but they may represent the best option in highly selected patients, such as those who are at high risk for extrahepatic recurrence or who are poor surgical candidates.

Right portal vein embolization before right hepatectomy for unilobar colorectal liver metastases reduces the intrahepatic recurrence rate

AIM

To assess the effect of portal vein embolization (PVE) on intrahepatic recurrence rate after right hepatectomy for unilobar colorectal liver metastases (CLM).

SUMMARY AND BACKGROUND

Recent research suggests that CLM could spread retrogradely through the portal vein. PVE may reduce tumor shedding by the occlusion of distal portal branches. However, no study reported the clinical effect of PVE on intrahepatic recurrence after CLM resection.

PATIENTS AND METHODS

Between 1995 and 2003, 44 patients requiring a right hepatectomy for unilobar CLM were operated in our institution. Right hepatectomy was performed after PVE in 23 patients (group A) and without PVE in 21 (group B). Surgical outcome and site of recurrence were analyzed.

RESULTS

The postoperative mortality was nil. Overall morbidity and transitory liver failure rates were similar in groups A and B (43.4% and 17.3% vs. 33.3% and 14.2%, respectively). The 3- and 5-year overall survival rates did not differ in group A and B patients (61.2% and 43.7% vs. 49.7% and 35.5%, respectively; P = 0.862). The disease-free survival rate was similar in both groups. Thirty patients (68.2%) developed recurrences. Recurrences were intrahepatic in 22 patients (50%) and extrahepatic in 27 (61.3%). Intrahepatic recurrence rate was significantly lower in group A compared with group B (26.0% vs. 76.1% respectively; P < 0.001). PVE, number of CLM, and administration of neoadjuvant chemotherapy were independent prognostic factors for intrahepatic recurrences.

CONCLUSION

This study showed that PVE reduces intrahepatic recurrence rate after right hepatectomy for unilobar CLM.

Intensive follow-up after liver resection for colorectal liver metastases: results of combined serial tumour marker estimations and computed tomography of the chest and abdomen - a prospective study

The aim of the study was to prospectively evaluate an intensive follow-up programme using serial tumour marker estimations and contrast-enhanced computed tomography (CT) of the chest and abdomen in patients undergoing potentially curative resection of colorectal liver metastases. Seventy-six consecutive patients having undergone potentially curative resections of colorectal liver metastases in a single unit were followed up with a protocol of 3 monthly carcinoembryonic antigen and carbohydrate antigen 19-9 estimations and contrast-enhanced spiral CT of the chest, abdomen and pelvis for the first 2 years following surgery and 6 monthly thereafter. The median period of follow-up was 24 months (range 18-60). Recurrent tumour was classed as early if within 6 months of liver resection. Thirty-seven of the 76 patients (49%) developed recurrence on follow-up. Nineteen recurrences were in the liver alone (51%), 16 liver and extrahepatic (43%) and two extrahepatic alone (6%). Of the 19 patients with isolated liver recurrence, eight developed within 6 months of liver resection none of which were resectable. Of the 11 recurrences after 6 months, five (45%) were resectable. Of the 37 recurrences, CT indicated recurrence despite normal tumour markers in 19 patients. Tumour markers suggested recurrence before imaging in 12 and concurrently with imaging in 6. In the 12 patients who presented with elevated tumour markers before imaging, there was a median lag period of 3 months (range 1-21) in recurrence being detected on further serial imaging. Seventeen patients who developed recurrence had normal tumour markers before initial resection of their liver metastases. Of these 17, 10 (58%) had an elevation of tumour markers associated with recurrence. Over a median follow-up of 2 years following liver resection, the use of CT or tumour markers alone would have failed to demonstrate early recurrence in 12 and 18 patients respectively. A combination of tumour markers and CT detected significantly more (P < 0.05) recurrence than either modality alone. Tumour markers and CT should be used in combination in the follow-up of patients with resected colorectal liver metatases, including patients whose markers are normal at the time of initial liver resection.

Compensatory recovery of liver mass by Akt-mediated hepatocellular hypertrophy in liver-specific STAT3-deficient mice

BACKGROUND/AIMS

Liver regeneration following hepatectomy is complicated and involves a variety of interacting factors. The present study was designed to study the roles of proliferation and hypertrophy of hepatocytes in liver regeneration following hepatectomy in liver-specific STAT3-knockout (LS3-KO) mice lacking mitogenic activity.

METHODS

Partial hepatectomy was performed in LS3-KO and control mice. Liver regeneration was estimated by the liver weight, cell proliferation and cell size, and the related cellular signals were analyzed.

RESULTS

Proliferation of hepatocytes following PH was markedly suppressed in LS3-KO mice with reduced cyclinD1 transcript. However, liver mass recovered sufficiently following PH in LS3-KO mice almost equal to that of control mice. Analysis of hepatocellular growth revealed that cell size following hepatectomy was significantly larger in LS3-KO mice than in control mice. Hepatectomy induced immediate but transient phosphorylation of Akt, p70S6K, mTOR and GSK-3beta in LS3-KO mice much more than in control mice. Additionally, adenoviral transfection of dominant negative mutant of Akt to control and LS3-KO mice led to insufficient liver regeneration following hepatectomy.

CONCLUSIONS

PI3-K/Akt-mediated responsive hepatocellular hypertrophy may be essential for liver regeneration following hepatectomy and sufficiently compensated liver regeneration even in STAT3-deficient liver, in which cell proliferation is impaired.

Phase II trial of carcinoembryonic antigen radioimmunotherapy with 131I-labetuzumab after salvage resection of colorectal metastases in the liver: five-year safety and efficacy results

PURPOSE

Although complete resection (R0) of liver metastases (LM) remains the treatment of choice for colorectal cancer (CRC) patients amenable to curative therapy, only approximately one third survive for 5 years. The objective of this phase II study was to evaluate the safety and efficacy of radioimmunotherapy (RAIT) after salvage resection of LM.

PATIENTS AND METHODS

Twenty-three patients who underwent surgery for LM of CRC received a dose of 40 to 60 mCi/m2 of 131I-labetuzumab, which is a humanized monoclonal antibody against carcinoembryonic antigen. Safety (n = 23), disease-free survival (DFS; n = 19), and overall survival (OS; n = 19) were determined.

RESULTS

With a median follow-up of 64 months, the median OS time from the first liver resection for RAIT patients was 68.0 months (95% CI, 46.0 months to infinity), and the median DFS time was 18.0 months (95% CI, 11.0 to 31.0 months). The 5-year survival rate was 51.3%. RAIT benefited patients independently of bilobar involvement, size and number of LM, and resection margins. The major adverse effect was transient myelosuppression, resulting mostly in grade < or = 3 neutropenia and/or thrombocytopenia.

CONCLUSION

Because both the median OS and 5-year survival rates seem to be improved with adjuvant RAIT after complete LM resection in CRC, compared with historical and contemporaneous controls not receiving RAIT, these results justify further evaluation of this modality in a multicenter, randomized trial.

Cancer cell dissemination during curative surgery for colorectal liver metastases

AIM

The amount of cancer cells disseminated during curative surgery for colorectal liver metastases (CRLM) may be responsible for recurrence. Haematogenous and intrahepatic cancer cell dissemination was evaluated, and its impact on cancer recurrence was assessed.

METHOD

Twenty patients with resectable CRLM were included in a prospective study. Twelve patients underwent curative resection for 21 metastases. Ten selected metastases in eight patients were treated with radiofrequency ablation (RFA) followed by resection at the same operative session. Cancer cell dissemination was determined before, during and after surgery using 'real time' quantitative RT-PCR assay, based on detection and quantification of CEA and CK20 mRNA transcripts.

RESULTS

Circulating cancer cells were detected in 80% and intrahepatic cancer cells in 37% of the patients, though without impact on cancer recurrence. The amounts of disseminated cancer cells were significantly increased after surgery. This increase was similar in patients treated with and without RFA. RFA caused complete tumour destruction.

CONCLUSION

Curative surgery for CRLM significantly increases the amount of disseminated cancer cells. Radiofrequency ablation can completely destroy selected resectable CRLM without excessive cancer cell dissemination. Neither haematogenous nor intrahepatic cancer cell dissemination were related to cancer recurrence in this small patient series.

Current preventive treatment for recurrence after curative hepatectomy for liver metastases of colorectal carcinoma: A literature review of randomized control trials

To review the preventive approaches for recurrence after curative resection of hepatic metastases from colorectal carcinoma, we have summarized all available publications reporting randomized control trials (RCTs) covered in PubMed. The treatment approaches presented above include adjuvant intrahepatic arterial infusion chemotherapy, systemic chemotherapy, neoadjuvant chemotherapy, and immunotherapy. Although no standard treatment has been established, several approaches present promising results, which are both effective and tolerable in post-hepatectomy patients. Intrahepatic arterial infusion chemotherapy should be regarded as effective and tolerable and it increases overall survival (OS) and disease-free survival (DFS) of patients, while 5-fluorouracil-based systemic chemotherapy has not shown any significant survival benefit. Fortunately chemotherapy combined with hepatic arterial infusion and intravenous infusion has shown OS and DFS benefit in many researches. Few neoadjuvant RCT studies have been conducted to evaluate its effect on prolonging survivals although many retrospective studies and case reports are published in which unresectable colorectal liver metastases are downstaged and made resectable with neoadjuvant chemotherapy. Liver resection supplemented with immunotherapy is associated with optimal results; however, it is also questioned by others. In conclusion, several adjuvant approaches have been studied for their efficacy on recurrence after hepatectomy for liver metastases from colorectal cancer (CRC), but multi-centric RCT is still needed for further evaluation on their efficacy and systemic or local toxicities. In addition, new adjuvant treatment should be investigated to provide more effective and tolerable methods for the patients with resectable hepatic metastases from CRC.

Radiofrequency ablation of colorectal liver metastases

BACKGROUND

Untreated patients with colorectal liver metastases rarely survive 3 years, and the 3-year survival rate for patients treated with chemotherapy is 3%. The best survival rates are for the small subgroup that has operable disease, i.e., 39% at 5 years. Radiofrequency ablation (RFA) offers a new opportunity to destroy liver metastases in patients who are not surgical candidates because of disease distribution or comorbidity.

METHODS

Acceptance criteria were a maximum of four or five liver lesions with a maximum diameter of 4 or 5 cm and no evidence of active extrahepatic disease. Nearly all treatments were performed percutaneously using ultrasound, computed tomography, or magnetic resonance imaging (or some combination) for guidance and monitoring. RFA is a minimally invasive procedure that can be readily repeated. General anesthesia facilitates the procedure but is not essential. Multiple overlapping ablations are required to ensure optimal treatment in all but the smallest tumors.

RESULTS

In our cohort of 167 patients with colorectal liver metastases, 73 fulfilled the optimal acceptance criteria (5 or fewer tumors that were </=5 cm). The median survival periods were 38 months, with a 5-year survival rate of 30%, after the diagnosis of liver metastases and 31 months, with a 5-year survival rate of 25%, after the first ablation.

CONCLUSION

RFA increases the therapeutic options for patients with colorectal metastases. Until controlled trials can better define the role of RFA, there are several groups of patients who are not surgical candidates and can be considered for RFA.

Radio-frequency ablation of colorectal liver metastases in 167 patients

The objective of this paper is to report our results from a prospective study of 167 patients with colorectal liver metastases treated with radio-frequency ablation (RFA). Three hundred fifty-four treatments were performed in 167 patients, 99 males, mean age 57 years (34-87). The mean number of metastases was 4.1 (1-27). The mean maximum diameter was 3.9 cm (1-12). Fifty-one (31%) had stable/treated extra-hepatic disease. Treatments were performed under general anaesthesia using US and CT guidance and single or cluster water-cooled electrodes (Valleylab, Boulder, CO). All patients had been rejected for or had refused surgical resection. Eighty percent received chemotherapy. Survival data were stratified by tumour burden at the time of first RFA. The mean number of RFA treatments was 2.1 (1-7). During a mean follow-up of 17 months (0-89), 72 developed new liver metastases and 71 developed progressive extra-hepatic disease. There were 14/354 (4%) major local complications and 22/354 (6%) minor local complications. For patients with < or =5 metastases, maximum diameter < or =5 cm and no extra-hepatic disease, the 5-year survival from the time of diagnosis was 30% and from the time of first thermal ablation was 26%. Given that the 5-year survival for operable patients is a median of 32%, our 5-year survival of 30% is promising.