Microwave ablation of liver metastases guided by contrast-enhanced ultrasound: experience with 125 metastases in 39 patients

Survival outcomes and quality of life after percutaneous cryoablation for liver metastasis: A systematic review and meta-analysis

BACKGROUND

Liver metastasis is present in a wide range of malignancies, with colorectal cancer as the most common site. Several minimally invasive treatments have been suggested for managing hepatic metastases, and cryoablation is among them, yet not widely used. In this systematic review, we aimed to assess the effectiveness of percutaneous cryoablation in all types of liver metastases.

METHODS

A systematic search was performed in international databases, including PubMed, Scopus, Embase, and Web of Science, to find relevant studies reporting outcomes for percutaneous cryoablation in liver metastasis patients. In addition to baseline features such as mean age, gender, metastasis origin, and procedure details, procedure outcomes, including overall survival, local recurrence, quality of life (QoL), and complications, were extracted from the studies. Random-effect meta-analysis was performed to calculate the mean difference (MD) and 95% confidence interval for comparison of QoL.

RESULTS

We screened 2131 articles. Fifteen studies on 692 patients were included. Mean overall survival ranged from 14.5-29 months. The rate of local recurrence in the included studies ranged from 9.4% to 78%, and local control progression-free survival ranged from 1 to 31 months. The total QoL decreased one week after the cryoablation procedure (-3.08 [95% Confidence interval: -4.65, -1.50], p-value <0.01) but increased one month (5.69 [3.99, 7.39], p-value <0.01) and three months (3.75 [2.25, 5.24], p-value <0.01) after the procedure.

CONCLUSION

Cryoablation is an effective procedure for the treatment of liver metastases, especially in cases that are poor candidates for liver resection. It could significantly improve QoL with favorable local recurrence.

Long-term outcomes following percutaneous microwave ablation for colorectal cancer liver metastases

PURPOSE

To evaluate the overall survival (OS), local progression-free survival (PFS) and prognostic factors of patients with colorectal cancer liver metastases (CRLM) undergoing microwave ablation (MWA).

METHOD

A total of 132 patients were retrospectively enrolled who had been treated between 2010 and 2018. For the evaluation of survival rates, all patients were divided according to their indications (curative n = 57 and debulking (patients with additional non-target extrahepatic metastases) n = 75). In total, 257 ablations were evaluated for prognostic factors: number of liver metastases, primary tumor origin (PTO), diameter and volume of metastases, duration and energy of ablation.

RESULTS

The OS was 32.1 months with 93.2% of patients free from recurrence at 28.3 months (median follow-up time). The one- year and three-year OS were 82.72% and 41.66%, respectively. The OS and recurrence-free survival of the curative group were statistically significantly higher than the debulking group (p < .001). Statistically significant prognostic factors for OS included the location of the primary tumor (p < .038) and the number of metastases (all p < .017). Metastasis diameter and volume and ablation duration and energy had no significant correlation with survival (p > .05).

CONCLUSIONS

Satisfactory OS and local tumor PFS can be achieved in patients with CRLM using MWA with the number of metastases and the location of the primary tumor influencing the outcome of patients. The metastasis's size and the duration and energy used for ablation were not of significant prognostic value.

CalliSpheres drug-eluting beads transarterial-chemoembolization in the treatment of liver metastases from breast cancer: Initial experience in 14 patients

Breast cancer patients with liver metastases are associated with high mortality. However, no standardized treatment approach is available for these patients who have undergone chemotherapy and hormonal therapy. We aimed to assess the clinical outcomes of patients with breast cancer liver metastases (BCLM) who underwent drug-eluting beads used for transarterial-chemoembolization (DEB-TACE).We retrospectively enrolled 14 patients with 39 lesions who underwent DEB-TACE for liver metastases following mastectomy for primary breast cancer. The incidence of complications, overall survival (OS), and local tumor progression-free survival (PFS) were assessed.A total of 14 patients with 39 liver metastases were treated with DEB-TACE from July 2017 to July 2020. The objective response rates (ORR) and disease control rates (DCR) were 71.4% and 92.8% at the 3-month period and 50% and 71.4% at the 6-month period, respectively. During the follow-up period the local tumor PFS was 8.0 months. The median OS was 20.0 months (range, 8-40 months) and the 1-, 2-year OS rates were 84.4% and 47.4%, respectively. No severe complications caused by this technique were detected.DEB-TACE for BCLM was characterized as a low trauma technique, with a limited number of complications. The results indicated that this method was safe and effective for patients with BCLM and could be widely adopted as a palliative treatment in clinical practice.

Thermal ablation versus hepatic resection for the treatment of liver metastases from gastrointestinal stromal tumors: a retrospective study

Objective: The study aimed to compare effectiveness and safety of thermal ablation and hepatic resection in patients with liver metastases of gastrointestinal stromal tumors (GISTs).Method: A total of 55 patients (27 in the ablation group and 28 in the surgery group) with liver metastases were included. Overall survival (OS) and progression-free survival (PFS) were assessed with Kaplan-Meier's survival estimate curves. Univariate and multivariate regression analyses were carried out to identify potential prognostic factors.Results: The median OS was 102.0 months in the ablation group and 117.0 months in the surgery group (p = .875). The 1-, 3- and 5-year OS rates were 100%, 88.9% and 74.1% in the ablation group and 92.8%, 82.1% and 78.6% in the surgery group, respectively. The 1-, 3- and 5-year PFS rates were 48.1%, 25.9% and 18.5% in the ablation group and 67.8%, 64.3% and 64.3% in the surgery group, respectively. Multivariate analysis showed that preoperative tyrosine kinase inhibitor (TKI) treatment (progressive disease, PD) (HR, 13.985; 95% CI, 1.791-109.187; p = .012) was the only significant independent prognostic factor for OS. Tumor number (HR, 1.318; 95% CI, 1.021-1.702; p = .034) was identified as an independent predictor for PFS in multivariate analysis. There were fewer postoperative complications (18.5% vs. 78.6%, p = .001) and shorter lengths of hospital stay (8.0 vs. 16.5 days, p = .001) in the ablation group.Conclusion: Compared with resection, thermal ablation offered comparable OS for liver metastases of GISTs. Furthermore, thermal ablation had the advantages of fewer complications and shorter lengths of hospital stay.

Contrast-Enhanced Ultrasound Guidance for Interventional Procedures

Since its introduction, contrast-enhanced ultrasound (CEUS) has gained an important role in the diagnosis and management of abdominal and pelvic diseases. Contrast-enhanced ultrasound can improve lesion detection rates as well as success rates of interventional procedures when compared to conventional ultrasound alone. Additionally, CEUS enables the interventionalist to assess the dynamic enhancement of different tissues and lesions, without the adverse effects of contrast-enhanced computed tomography, such as exposure to ionizing radiation and nephrotoxicity from iodinated contrast material. This review article describes the various applications and advantages of the use of CEUS to enhance performance of ultrasound-guided interventions in the abdomen and pelvis.

The local efficacy and influencing factors of ultrasound-guided percutaneous microwave ablation in colorectal liver metastases: a review of a 4-year experience at a single center

PURPOSE

To investigate the clinical effectiveness and safety of ultrasound (US)-guided percutaneous microwave ablation (MWA) for colorectal liver metastasis (CRLM) and evaluate the influencing factors of local efficacy.

METHODS

From January 2013 to January 2017, 137 CRLM patients accepting US-guided percutaneous MWA were included. The 2450-MHz microwave ablation system and a cooled-shaft antenna were used. All patients were regularly followed up for at least 6 months. Technical success, complete ablation, local tumor progression (LTP), complications and side effects were assessed. Logistic regression analysis was used to identify the independent prognostic factors for LTP.

RESULTS

In total, 411 lesions (mean diameter 15.4 ± 7.2 mm, range 5-67 mm) were treated. Complete ablation was achieved in 99.27% (408/411) of lesions and 97.81% (134/137) of patients. LTP occurred in 5.35% (22/411) of lesions and 16.06% (22/137) of patients. LTP was more likely to occur in lesions larger than 3 cm in diameter (OR: 14.71; p < .001; 95% CI: 3.7 3-57.92), near a large vascular structure (OR: 7.04; p < .001; 95% CI: 2.41-20.60), near the diaphragm (OR: 4.02; p = .049; 95% CI: 1.05-16.11) and in patients with no response to chemotherapy before MWA (OR: 3.25; p = .032; 95% CI: 1.14-15.30). MWA was well tolerated, with a major complication rate of 3.65%, a minor complication rate of 8.03% and a mortality rate of 0%. Fever and pain were the most common side effects after MWA.

CONCLUSIONS

US-guided percutaneous MWA of CRLM is a safe and effective method that is expected to become a routine treatment for local tumor control of CRLM.

Use of Ultrasound Contrast Agents in Relation to Percutaneous Interventional Procedures: A Systematic Review and Pictorial Essay

The aim of this article is to provide an inventory of the use of contrast-enhanced ultrasound (CEUS) in relation to percutaneous interventional procedures. The article is structured into a systematic literature review followed by a clinical part relating to percutaneous CEUS-guided procedures. A literature search identified 3109 records. After abstract screening, 55 articles were analyzed and supplemented with pictorial material to explain the techniques. In conclusion, the best-evidenced indications for CEUS-guided interventions are biopsy and ablation of inconspicuous or B-mode-invisible tumors, intraprocedural ablation control and follow-up, as well as percutaneous transhepatic cholangiography and drainage procedures.

Microwave ablation combined with hepatic artery embolization for treatment of liver metastasis after surgery for colorectal cancer : Efficacy and effect on liver function

AIM

To compare the therapeutic effects and prognosis in patients with liver metastasis of colorectal cancer treated by transcatheter arterial chemoembolization (TACE) alone and those treated by TACE combined with microwave ablation (MWA).

METHODS

The clinical data of 84 patients with primary colorectal cancer treated at our hospital from January 2013 to January 2015 were retrospectively analyzed. The patients were divided into either a combination group (TACE combined with MWA; n = 40) or a TACE alone group (n = 44) according to different treatment plans. The therapeutic effect and adverse reactions were compared between the two groups, and the changes of liver function, quality of life, and survival were also compared.

RESULTS

At one month after treatment, the effective rate and disease control rate were significantly higher in the combination group than in the TACE alone group (77.5% vs 38.6%, 85.0% vs 56.8%, P < 0.05). After 1 wk of treatment, there was no significant difference in serum total bilirubin, ALT, or albumin levels in the two groups (t = 3.662, 2.816, 2.578, P > 0.05). During the treatment period, there was no significant difference in the incidence of nausea, vomiting, thrombocytopenia, leukocyte reduction, hemoglobin reduction, mucositis, cholinergic syndrome, or delayed diarrhea between the two groups (χ² = 1.056, 0.784, 1.022, 2.103, 0.668, P > 0.05). After 6 mo of treatment, the physiological status, emotional status, functional status, family and social status, and quality of life scores were significantly higher in the combination group than in the TACE group alone (t = 5.139, 6.052, 4.331, 4.508, 4.417, P < 0.05). There was no significant difference in the survival rates at six months and 1 year (χ² = 0.216, 1.492, P > 0.05), but the 2- and 3- year survival rates were significantly higher than those in the TACE alone group(χ² = 3.894, 4.017, P < 0.05).

CONCLUSION

Microwave ablation combined with TACE is effective in the treatment of liver metastases from colorectal cancer. Compared with TACE alone, microwave ablation combined with TACE can further improve the quality of life and prolong the survival time, without increasing the incidence of adverse reactions.

Locoregional Therapies for the Treatment of Hepatic Metastases from Breast and Gynecologic Cancers

Breast cancer is the most common women's malignancy in the United States and is the second leading cause of cancer death. More than half of patients with breast cancer will develop hepatic metastases; this portends a poorer prognosis. In the appropriately selected patient, there does appear to be a role for curative (surgery, ablation) or palliative (intra-arterial treatments) locoregional therapy. Gynecologic malignancies are less common and metastases to the liver are most often seen in the setting of disseminated disease. The role of locoregional therapies in these patients is not well reported. The purpose of this article is to review the outcomes data of locoregional therapies in the treatment of hepatic metastases from breast and gynecologic malignancies.

A preoperative mathematic model for computed tomographic guided microwave ablation treatment of hepatic dome tumors

Purpose

This study sought to prospectively evaluate the feasibility and safety of a preoperative mathematic model for computed tomographic(CT) guided microwave(MW) ablation treatment of hepatic dome tumors.

Methods

This mathematic model was a regular cylinder quantifying appropriate puncture routes from the bottom up. A total of 103 patients with hepatic dome tumors were enrolled and randomly divided into 2 groups based on whether this model was used or not: Group A (using the model; n = 43) versus Group B (not using the model; n = 60). All tumors were treated by CT-guided MW ablation and follow-up contrast CT were reviewed.

Results

The average number of times for successful puncture, average ablation time, and incidence of right shoulder pain were less in Group A than Group B (1.4 vs. 2.5, P = 0.001; 8.8 vs. 11.1 minutes, P = 0.003; and 4.7% vs. 20%, P = 0.039). The technical success rate was higher in Group A than Group B (97.7% vs. 85.0%, P = 0.032). There were no significant differences between the two groups in primary and secondary technique efficacy rates (97.7% vs. 88.3%, P = 0.081; 90.0% vs. 72.7%, P = 0.314). No major complications occurred in both groups.

Conclusion

The mathematic model of regular cylinder is feasible and safe for CT-guided MW ablation in treating hepatic dome tumors.

Local Ablation for Solid Tumor Liver Metastases: Techniques and Treatment Efficacy

BACKGROUND

Treatment options for liver metastases from solid tumors, such as colon cancer, breast cancer, neuroendocrine tumors, and sarcomas, have expanded in recent years and now include nonresection methods.

METHODS

The literature focused on the treatment of liver metastases was reviewed for technique, perioperative, and long-term outcomes specifically related to local ablation techniques for liver metastases.

RESULTS

Ablation modalities have become popular as therapies for patients who are not appropriate candidates for surgical resection. Use of these techniques, alone or in combination with other liver-directed therapies (and often systemic therapy), has extended the rate of survival for patients with liver metastases and, at times, offers nearly equivalent disease-free survival rates to surgical resection.

CONCLUSIONS

Although surgical resection remains the optimal treatment for liver metastasis, local options, including microwave ablation and radiofrequency ablation, can offer similar long-term local control in appropriately selected patients.

Microwave ablation in primary and secondary liver tumours: technical and clinical approaches

Thermal ablation is increasingly being utilised in the treatment of primary and metastatic liver tumours, both as curative therapy and as a bridge to transplantation. Recent advances in high-powered microwave ablation systems have allowed physicians to realise the theoretical heating advantages of microwave energy compared to other ablation modalities. As a result there is a growing body of literature detailing the effects of microwave energy on tissue heating, as well as its effect on clinical outcomes. This article will discuss the relevant physics, review current clinical outcomes and then describe the current techniques used to optimise patient care when using microwave ablation systems.

International guidelines for contrast-enhanced ultrasonography: ultrasound imaging in the new millennium

The intent of this review is to discuss and comment on common clinical scenarios in which contrast-enhanced ultrasonography (CEUS) may play a decisive role and to illustrate important points with typical cases. With the advent of CEUS, the scope of indications for ultrasonography has been dramatically extended, and now includes functional imaging and tissue characterization, which in many cases enable tumor diagnosis without a biopsy. It is virtually impossible to imagine the practice of modern medicine as we know it in high-income countries without the use of imaging, and yet, an estimated two thirds of the global population may receive no such care. Ultrasound imaging with CEUS has the potential to correct this inequity.

CT imaging during microwave ablation: analysis of spatial and temporal tissue contraction

PURPOSE

To analyze the spatial distribution and temporal development of liver tissue contraction during high-temperature ablation by using intraprocedural computed tomography (CT) imaging.

METHODS

A total of 46 aluminum fiducial markers were positioned in a 60 × 45 mm grid, in a single plane, around a microwave ablation antenna in each of six ex vivo bovine liver samples. Ablations were performed for 10 min at 100 W. CT data of the liver sample were acquired every 30 s during ablation. Fiducial motion between acquisitions was tracked in postprocessing and used to calculate measures of tissue contraction and contraction rates. The spatial distribution and temporal evolution of contraction were analyzed.

RESULTS

Fiducial displacement indicated that the zone measured postablation was 8.2 ± 1.8 mm (∼20%) smaller in the radial direction and 7.1 ± 1.0 mm (∼10%) shorter in the longitudinal direction than the preablation tissue dimension. Therefore, the total ablation volume was reduced from its preablation value by approximately 45%. Very little longitudinal contraction was noted in the distal portion of the ablation zone. Central tissues contracted more than 60%, which was near an estimated limit of ∼70% based on initial water content. More peripheral tissues contracted only 15% in any direction. Contraction rates peaked during the first 60 s of heating with a roughly exponential decay over time.

CONCLUSIONS

Ablation zones measured posttreatment are significantly smaller than the pretreatment tissue dimensions. Tissue contraction is spatially dependent, with the greatest effect occurring in the central ablation zone. Contraction rate peaks early and decays over time.

Local tumour progression after ultrasound-guided microwave ablation of liver malignancies: risk factors analysis of 2529 tumours

OBJECTIVES

To identify the incidence and risk factors that predict local tumour progression (LTP) after ultrasound-guided percutaneous microwave ablation (MWA) of liver malignancies.

MATERIALS AND METHODS

One thousand two hundred and nine patients with 2,529 malignant nodules (mean size 2.8 ± 1.4 cm, range 0.9-8.0 cm) were treated by MWA between July 2005 and December 2012. The influence of 11 factors on the risk of LTP was assessed. Univariate Kaplan-Meier and Cox proportional hazard models were used for statistical analysis.

RESULTS

The overall LTP was 4.2 % per tumour and 8.6 % per patient with a median follow-up of 20.3 months. LTP per tumour was 4.3 % for primary liver cancer and 4.1 % for metastases (p = 0.32). The survival of LTP and free-LTP patients at 1, 3, and 5 years was 92.4 %, 71.6 %, and 45.1 %, respectively, and 92.9 %, 70.1 %, and 52.4 %, respectively (p = 0.93). By univariate analysis, tumour location, size and ablation time were significant risk factors of LTP. Multivariate analysis identified tumour size (>3.0 cm) to be the only independent predictor of LTP.

CONCLUSIONS

MWA of liver malignancies achieves a relatively low-incidence LTP, although LTP risk significantly increases if tumour size >3.0 cm. The technique seems to be appropriate even for patients with a tumour at a risk location.

KEY POINTS

• Microwave ablation of liver malignancies achieves a low incidence local tumour progression. • LTP risk significantly increases if the tumour size is >3.0 cm. • MWA seems to be appropriate even for patients with a tumour at a risk location.

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.

Percutaneous microwave ablation of hepatic tumors: prospective evaluation of postablation syndrome and postprocedural pain

PURPOSE

To prospectively investigate the frequency and severity of postablation syndrome (PAS) and postprocedural pain in a cohort of patients undergoing hepatic microwave ablation.

MATERIALS AND METHODS

From March 2009 to November 2011, 54 consecutive patients undergoing microwave ablation for liver tumors were enrolled. A questionnaire was administered to investigate PAS and pain at 1, 7, and 40 days after ablation. Four patients did not complete all three questionnaires and were excluded from the analysis. Additionally, laboratory tests with results known to significantly increase or decrease after ablation were performed, and ablation parameters were recorded. Potential predictors of PAS and pain at 1 and 7 days were evaluated by a logistic regression model.

RESULTS

Fifty patients underwent a single microwave ablation session, 33 for hepatocellular carcinoma (HCC) and 17 for liver metastasis. Median ablation volumes on computed tomography were 31 cm(3) for HCC and 42 cm(3) for metastasis. Sixty percent of patients experienced PAS in the first week. Aspartate aminotransferase (AST) levels after ablation were significantly associated with PAS during postprocedure days 1-7. Median visual analog scale scores for pain at the puncture site were 1 and 0.24 at 1 and 7 days, respectively. The risk of having at least moderate pain in the first week was significantly related to ablation volume and time and postablation increase in AST level.

CONCLUSIONS

The incidence and severity of PAS with hepatic microwave ablation is similar to that reported for radiofrequency ablation, with the best predictive factor being postablation AST level elevation. Postablation pain was best predicted by total ablation volume and AST level.

Percutaneous cryoablation of liver metastases from breast cancer: initial experience in 17 patients

AIM

To assess the feasibility, safety, and effectiveness of percutaneous cryoablation for the treatment of liver metastases from breast cancer.

MATERIALS AND METHODS

This study included 39 liver metastases in 17 female breast cancer patients who underwent computed tomography (CT)-guided percutaneous cryoablation. The mean age of the cohort was 55 years (range 30-66 years). The tumour response was evaluated by CT performed before treatment, 1 month after treatment, and every 3 months thereafter. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC QLQ-C30) was used to assess the patients' quality of life before, 1 week, 1 month, and 3 months after cryoablation. The primary endpoints were technique effectiveness, quality of life, and complications.

RESULTS

The technical success rate was 92% with no major complication reported. At the 1-month follow-up, the primary technique effectiveness was 87.1% (34 of 39 tumours). At the 3-months follow-up, local tumour progression was observed in six of 39 lesions (15.4%). The 1-year survival from the time of cryoablation was 70.6%. The quality of life symptoms and functioning scales were preserved in patients alive at 3 months after cryoablation. The global quality of life, mean value of "pain" and "fatigue" between 3 months after cryoablation and prior to treatment showed statistically significant differences, but no clinical significance.

CONCLUSIONS

Cryoablation is a safe and effective ablative therapy, providing a high rate of local tumour control in breast cancer liver metastases.

Microwave ablation of liver metastases to overcome the limitations of radiofrequency ablation

PURPOSE

The purpose of our study was to evaluate technical success, effectiveness and safety of microwave ablation (MWA) in patients with unresectable liver metastases, where radiofrequency ablation (RFA) presents some limits.

MATERIALS AND METHODS

Twenty-five patients (17 men, 8 women) with 31 liver metastases >3 cm or located near vessels (>3 mm) were treated in a total of 29 sessions. Tumours were subdivided as follows: colorectal metastases (n=21) and no colorectal metastases (n=10). All procedures were performed percutaneously under ultrasound (US) guidance. Follow-up was performed with computed tomography (CT) scan at 1, 3, 6 and 12 months after treatment; mean follow-up period was 12.04 (range, 3-36) months. Technical success, mean disease-free survival, effectiveness and safety were evaluated.

RESULTS

Technical success was obtained in all cases. Mean disease-free survival was of 20.5 months. Local recurrence was recorded in 12.9% of metastases treated (4/31). No major complications were recorded. The rate of minor complications was 44.8% (13/29 sessions). Mortality at 30 days was 0%.

CONCLUSIONS

Percutaneous MWA of liver metastases >3 cm or located near vessels (>3 mm) can be considered a valid and safe option, probably preferable to RFA. Further studies are required to confirm these encouraging initial results.

Designing liver resections and pushing the envelope with resections for hepatic colorectal metastases

Current concepts in the management of hepatic metastases have changed dramatically over the past two decades. Multidisciplinary therapies including chemotherapy, surgery, and regional therapy have alone and in combination significantly improved the survival of patients with metastatic colorectal cancer. Conditions that were previously considered hopeless and treated merely for palliation can now be approached with curative intent. In this paper, we review the surgical treatment for colorectal cancer liver metastasis (CRLM) and describe a paradigm-shift in the management of complex heretofore-considered unresectable CRLM. Utilizing advanced multidisciplinary treatment strategies has improved the prognosis of patients with stage IV colorectal cancer to the point where we may question whether CRLM are now a chronic disease.

Efficacy and safety of thermal ablation in patients with liver metastases

OBJECTIVE

Thermal ablation is safe and effective for the treatment of hepatocellular carcinoma. However, it remains problematic with respect to liver metastases. Here, we aimed to evaluate the efficacy and safety of thermal ablation in patients with liver metastases.

METHODS

Eighty-nine patients with 132 liver metastases measuring 0.8-5.0 cm were treated with microwave ablation (MWA) or radiofrequency ablation (RFA). The primary lesions were colorectal cancer in 38 cases and others in 51, respectively. Local tumor control, complications, and long-term survival were analyzed.

RESULTS

Complete ablation was achieved in 117 of 132 (88.6%) nodules. Seventeen of the 117 (14.5%) successfully treated nodules developed local recurrence. In a univariate analysis, a significant trend toward a lower local recurrence rate with MWA was observed (8.6% for MWA vs. 20.3% for RFA, P=0.072). Multivariate analysis showed that number of cycles of chemotherapy was the significant prognostic factor for overall recurrence (P=0.015), whereas disease-free interval was the significant prognostic factor for distant recurrence (P=0.030). Ablation modality showed potential prognostic significance for local recurrence (P=0.053). Major complications occurred in 1.1% of patients. No procedure-related mortalities were observed. The 1, 2, 3, and 5-year overall survival rates after the initial ablation were 84.9, 59.6, 48.8, and 36.3%, respectively.

CONCLUSION

Thermal ablation is a safe and effective treatment for patients with liver metastases. MWA has the potential to result in less local recurrence than RFA.

Small liver colorectal metastases treated with percutaneous radiofrequency ablation: local response rate and long-term survival with up to 10-year follow-up

PURPOSE

To determine the long-term (10-year) survival of patients with colorectal liver metastases treated with radiofrequency (RF) ablation and systemic chemotherapy with intention to treat.

MATERIALS AND METHODS

Institutional review board approval was obtained for this study. From 1997 to 2006, 99 consecutive patients with 202 small (0.8-4.0 cm; mean: 2.2 cm ± 1.1) metachronous colorectal liver metastases underwent ultrasonography-guided percutaneous RF ablation with internally-cooled electrodes in association with systemic chemotherapy. Patients ineligible for surgery (n = 80) or whose lesions were potentially resectable and who refused surgery (n = 19) were included. Patients were followed up with contrast agent-enhanced computed tomography and/or magnetic resonance imaging for a minimum of 3 years to more than 10 years after RF ablation (n = 99, 67, 49, and 25 for 3, 5, 7, and 10 or more years, respectively). Overall local response rates and long-term survival rates were assessed. For each of these primary endpoints, Kaplan-Meier curves were generated and log-rank tests were used to assess for statistically significant differences.

RESULTS

Primary and secondary technical success rates were 93.1% (188 of 202) and 100% (14 of 14), respectively. Local tumor progression occurred in 11.9% (24 of 202) metastases, and 54.2% (13 of 24) of these were re-treated. Patient survival rates increased with re-treatment versus no re-treatment (P < .001). At follow-up, 125 new liver metastases were found, and of these 32.8% (41 of 125) were treated with RF ablation. Overall survival rates were 98.0%, 69.3%, 47.8%, 25.0%, and 18.0% (median: 53.2 months) at 1, 3, 5, 7, and 10 years, respectively. The major complication rate was 1.3% (two of 156), and there were no procedure-related deaths. At the time this article was written, 32.3% (32 of 99) of the patients were alive, and 67.7% (67 of 99) were deceased, with a median follow-up of 72 months.

CONCLUSION

Adding RF ablation to systemic chemotherapy achieved local control in a large majority of metachronous colorectal liver metastases. The 3- to 10-year survival rates of this relatively large series of patients were essentially equivalent to those of most surgical series reported in the literature.

Thermal ablation therapies in patients with breast cancer liver metastases: a review

BACKGROUND

The liver is involved in about half of patients with metastatic breast cancer. Unfortunately systemic chemotherapy as the treatment of choice is limited. Due to multifocality and/or insufficient remnant liver volume, the majority of liver metastases are also unresectable. Currently, thermal ablations are used in these patients with acceptable impact.

METHODS

We reviewed studies on radiofrequency ablation (RFA), laser-induced thermotherapy (LITT) and microwave ablation (MWA) regarding local tumour response, progression and survival indexes in patients with breast cancer liver metastases (BCLM).

RESULTS

The reviewed literature showed positive response rates of 63 % to 97 % in RF-ablated lesions, 98.2 % in LITT-treated lesions and 34.5-62.5 % in MW-ablated lesions. Median survival was 10.9-60 months using RFA, 51-54 months after LITT and 41.8 months using MWA. Five-year survival rates were 27-30 %, 35 % and 29 %, respectively. Local tumour progression ranged from 13.5 % to 58 % using RFA, 2.9 % with LITT and 9.6 % with MWA.

CONCLUSION

The reviewed literature demonstrated that ablation therapies either as single therapy or combined with other locoregional therapies are a good alternative as an adjunction to resection in patients with resectable lesions or with positive response using chemotherapy. However, multicentre randomised studies should be conducted to obtain further evidence of the benefits of these treatments in patients with BCLM.