Inoperable colorectal liver metastases: a declining entity?

Prospective diagnostic test accuracy comparison of computed tomography during arterial portography and Primovist magnetic resonance imaging in the pre-operative assessment of colorectal cancer liver metastases

OBJECTIVES

To assess and compare the accuracy and inter-observer agreement for the detection of liver lesions using Primovist magnetic resonance imaging (pMRI) and computed tomography during arterial portography (CTAP).

METHODS

Patients evaluated at St George Hospital Liver Unit for colorectal liver metastases (CRCLM) underwent CTAP as part of standard staging. pMRI was added to the pre-operative assessment. Two radiologists reported CTAP and two reported pMRI. The sensitivity and specificity of CTAP and pMRI were calculated using histopathology as the gold standard.

RESULTS

Complete data were available for 62 patients corresponding to 219 lesions confirmed on histopathology. Agreement on the detection of lesions between the two radiologists that reported pMRI was higher than for CTAP (Kappa = 0.80 versus 0.74). Specificity of lesion detection for pMRI was 0.88 and 0.83 for CTAP (P = 0.112). Sensitivity for pMRI was 0.83 and 0.81 for CTAP. For patients who had chemotherapy before evaluation, pMRI had a significantly higher specificity than CTAP (0.79 versus 0.63, P = 0.011).

CONCLUSIONS

pMRI is less invasive, has a good inter-observer agreement, has comparable sensitivity and specificity to CTAP in the pre-chemotherapy population and demonstrates better specificity in patients assessed post-chemotherapy. pMRI is a valid alternative to CTAP in the assessment of CRCLM.

Thermal ablation of liver metastases from colorectal cancer: radiofrequency, microwave and laser ablation therapies

Surgery is currently considered the treatment of choice for patients with colorectal cancer liver metastases (CRLM) when resectable. The majority of these patients can also benefit from systemic chemotherapy. Recently, local or regional therapies such as thermal ablations have been used with acceptable outcomes. We searched the medical literature to identify studies and reviews relevant to radiofrequency (RF) ablation, microwave (MW) ablation and laser-induced thermotherapy (LITT) in terms of local progression, survival indexes and major complications in patients with CRLM. Reviewed literature showed a local progression rate between 2.8 and 29.7 % of RF-ablated liver lesions at 12-49 months follow-up, 2.7-12.5 % of MW ablated lesions at 5-19 months follow-up and 5.2 % of lesions treated with LITT at 6-month follow-up. Major complications were observed in 4-33 % of patients treated with RF ablation, 0-19 % of patients treated with MW ablation and 0.1-3.5 % of lesions treated with LITT. Although not significantly different, the mean of 1-, 3- and 5-year survival rates for RF-, MW- and laser ablated lesions was (92.6, 44.7, 31.1 %), (79, 38.6, 21 %) and (94.2, 61.5, 29.2 %), respectively. The median survival in these methods was 33.2, 29.5 and 33.7 months, respectively. Thermal ablation may be an appropriate alternative in patients with CRLM who have inoperable liver lesions or have operable lesions as an adjunct to resection. However, further competitive evaluation should clarify the efficacy and priority of these therapies in patients with colorectal cancer liver metastases.

Changing trends in the presentation of colorectal liver metastases in a single hepatobiliary tertiary referral centre over fourteen years

AIM

National Institute for Clinical Excellence guidelines suggest that patients who have undergone potentially curative treatment for colorectal cancer (CRC) should be followed up for 3 years. The aim of this study was to investigate whether the time to presentation with colorectal liver metastases (CRLM) has changed over time. This information, which is currently unknown, may inform future decisions regarding follow-up.

METHODS

Patients presenting with metachronous isolated liver metastases between 1997 and 2011 were included. Timings of presentation with CRLM, rates of liver resection, survival data and factors associated with delayed presentation were investigated.

RESULTS

269 patients were included in the study. Those having their primary CRC resection between 1997 and 2007 presented earlier with liver metastases over time (r = -0.33, 95% CI -0.45 to -0.20). However, 26% of patients who developed CRLM did so beyond 3 years. There was no significant difference in rates of liver resections for those presenting within, or beyond, 3 years (p = 0.21). There was no significant difference in survival for those presenting with resectable CRLM within, or beyond, 3 years (Exp(b) = 0.60, 95% CI 0.28-1.28). No factors associated with late presentation were identified.

CONCLUSIONS

These results suggest that CRC follow-up should be extended to 5 years. Follow-up interventions should be more frequent in the early stages reflecting the trend towards earlier presentation with CRLM. The economic implications of extending follow-up compare favourably to other NHS funded initiatives.

Analysis of prognostic factors in patients with colorectal cancer with liver metastases

AIM: To explore prognostic factors in patients with colorectal cancer with liver metastases.

METHODS: The survival and prognostic factors in 138 patients with liver metastases from colorectal cancer, who had complete follow-up data, were retrospectively assessed by Kaplan-Meier analysis and multivariate regression analysis.

RESULTS: The median survival time of the 138 patients was 18.3 months. Univariate analysis demonstrated that age (P = 0.460), primary tumor site (P = 0.568), primary tumor size (P = 0.250), and histological grade of primary tumor (P = 0.589) had no significant correlation with the overall survival. However, gender (P = 0.048), pretreatment serum CEA level (P = 0.023), number (P = 0.000) and size (P = 0.001) of liver metastases, lymphatic invasion (P = 0.001), and resection of liver metastases (P = 0.002) were all independently related with the prognosis of patients. Multivariate regression analysis showed that pretreatment serum CEA level (P = 0.028), number (P = 0.001) and size (P = 0.001) of liver metastases, lymphatic invasion (P = 0.049), and resection of liver metastases (P = 0.003) were key factors affecting the prognosis of patients with liver metastases from colorectal cancer.

CONCLUSION: Pretreatment serum CEA level, number and size of liver metastases, lymphatic invasion, and resection of liver metastases are independent prognostic factors for colorectal cancer with liver metastases.

Ablative therapies for colorectal liver metastases: a systematic review

AIM

The standard treatment for colorectal liver metastases (CRLM) is surgical resection. Only 20-30% of patients are deemed suitable for surgery. Recently, much attention has focused on ablative therapies either to treat unresectable CRLM or to extend the margins of resectability. This review aims to assess the long-term outcome and complication rates of various ablative therapies used in the management of CRLM.

METHOD

A literature search was performed of electronic databases including Medline, Cochrane Collaboration Library and the National Library of Medicine's ClinicalTrials.gov. Inclusion criteria were ablation for CRLM with minimum 1 year follow-up and >10 patients, published between January 1994 and January 2010.

RESULTS

In all, 226 potentially relevant studies were identified, of which 75 met the inclusion criteria. Cryotherapy (26 studies) had local recurrence rates of 12-39%, with mean 1-, 3- and 5-year survival rates of 84%, 37% and 17%. The major complication rate ranged from 7% to 66%. Microwave ablation (13 studies) had a local recurrence rate of 5-13%, with a mean 1-, 3- and 5-year survival of 73%, 30% and 16%, and a major complication rate ranging from 3% to 16%. Radiofrequency ablation (36 studies) had a local recurrence rate of 10-31%, with a mean 1-, 3- and 5-year survival of 85%, 36% and 24%, with major complication rate ranging from 0% to 33%.

CONCLUSION

Ablative therapies offer significantly improved survival compared with palliative chemotherapy alone with 5-year survival rates of 17-24%. Complication rates amongst commonly used techniques are low.

Hepatic tumor ablation

Ablation of liver tumors is part of a multimodality liver-directed strategy in the treatment of various tumors. The goal of ablation is complete tumor destruction, and ultimately improvement of quality and quantity of life for the patient. Technology is evolving rapidly, with important improvements in efficacy. The current state of ablation technology and indications for ablation are described in this review.

Systematic review of randomized and nonrandomized trials of the clinical response and outcomes of neoadjuvant systemic chemotherapy for resectable colorectal liver metastases

BACKGROUND

Neoadjuvant chemotherapy prior to hepatectomy in patients with resectable colorectal liver metastases (CLM) may facilitate the resectability of the liver lesions and treat occult metastasis but may also lead to hepatic parenchyma damage. There is argument over the oncologic benefit of this practice in patients who would already be suitable for a curative hepatectomy.

METHODS

Extensive literature search of databases (MEDLINE and PubMed) to identify published studies of preoperative systemic chemotherapy for resectable CLM was undertaken with clinical response to treatment and survival outcomes as the endpoints.

RESULTS

Twenty-three studies were reviewed: 1 phase III randomized control trial, 3 phase II studies, and 19 observational studies, comprising 3,278 patients. Objective (complete/partial) radiological response was observed in 64% (range 44-100%) [complete 4% (range 0-38%), partial 52% (range 10-90%)] of patients after neoadjuvant chemotherapy. Pathologically, a median of 9% (range 2-24%) and 36% (range 20-60%) had complete and partial response, respectively. Of patients, 41% (range 0-65%) had stable or progressive disease whilst on neoadjuvant chemotherapy. Median disease-free survival (DFS) was 21 (range 11-40) months. Median overall survival (OS) was 46 (range 20-67) months.

CONCLUSION

Current evidence suggests that objective response to neoadjuvant chemotherapy may be achieved with improvement in DFS in patients with resectable CLM. A prospective randomized trial of neoadjuvant therapy versus adjuvant therapy after liver resection is required to determine the optimal perisurgical treatment regimen.