[Radiofrequency ablation of malignant hepatic tumors. Preliminary experience apropos of 25 cases]

Complications of intraoperative radiofrequency ablation of liver metastases

BACKGROUND

Intraoperative radiofrequency ablation (IRFA) of liver metastases can be used to treat patients with complex tumours that are unsuitable for parenchymal resection alone. This systematic review assesses the frequency, patterns and severity of complications associated with this procedure.

METHODS

We carried out a bibliographic search on MEDLINE focused on IRFA for liver metastases, excluding hepatocarcinomas, and on intraoperative use, excluding percutaneous application.

RESULTS

Thirty papers published between 1999 and 2007 were analysed. They covered a total of 2822 patients and 1755 IRFA procedures. The indications and techniques for IRFA differ from those for percutaneous treatment, as do associated results and complications. Specific complications associated with IRFA, such as liver abscesses, biliary stenoses and vascular thromboses, are directly correlated with the indications and associated procedures. Published results should be interpreted with caution as IRFA can be used alone or combined with parenchymal resection.

CONCLUSIONS

Specific complications related to IRFA are rare, especially for lesions of <35 mm in size located far from a main biliary duct, when additional septic procedures are not used. A lesion-by-lesion approach based on the benefit : risk ratio should therefore be used in the process of making surgical decisions. Combining resection with IRFA leads to higher morbidity, especially in difficult patients with numerous bilateral lesions, but may be necessary to achieve R0 (microscopically negative margins) outcomes.

Influence de la proximité des gros vaisseaux sur les résultats du traitement des carcinomes hépato-cellulaires par radiofréquence : une étude contrôlée

PURPOSE

To evaluate the risk of radiofrequency ablation treatment failure for hepatocellular carcinomas (HCC) next to large vessels.

MATERIALS AND METHODS

Between May 2000 and October 2002, from a total of 83 patients treated by radiofrequency ablation for HCC in a single center, 13 patients with tumor<or=3.5 cm contacting a vessel >or=3 mm in diameter (Group A) were matched with 13 patients with similar size tumors located away from large vessels (Group B). Immediate response and recurrence rate were evaluated on CT.

RESULTS

After mean follow-up interval of 39+/-16.5 months for Group A and 39+/-14 months for Group B, local recurrence rates were 7/12 versus 1/12 respectively (p=0.03). For Group A, 6/7 local recurrences clearly contacted a large vessel.

CONCLUSION

The cooling effect from flowing blood in large vessels markedly increases the rate of local failure of radiofrequency ablation for small HCC located near large vessels.

Practical questions in liver metastases of colorectal cancer: general principles of treatment

Liver metastases of colorectal cancer are currently treated by multidisciplinary teams using strategies that combine chemotherapy, surgery and ablative techniques. Many patients classically considered non-resectable can now be rescued by neoadjuvant chemotherapy followed by liver resection, with similar results to those obtained in initial resections. While many of those patients will recur, repeat resection is a feasible and safe approach if the recurrence is confined to the liver. Several factors that until recently were considered contraindications are now recognized only as adverse prognostic factors and no longer as contraindications for surgery. The current evaluation process to select patients for surgery is no longer focused on what is to be removed but rather on what will remain. The single most important objective is to achieve a complete (R0) resection within the limits of safety in terms of quantity and quality of the remaining liver. An increasing number of patients with synchronous liver metastases are treated by simultaneous resection of the primary and the liver metastatic tumours. Multilobar disease can also be approached by staged procedures that combine neoadjuvant chemotherapy, limited resections in one lobe, embolization or ligation of the contralateral portal vein and a major resection in a second procedure. Extrahepatic disease is no longer a contraindication for surgery provided that an R0 resection can be achieved. A reverse surgical staged approach (liver metastases first, primary second) is another strategy that has appeared recently. Provided that a careful selection is made, elderly patients can also benefit from surgical treatment of liver metastases.

Local recurrence after hepatic radiofrequency coagulation: multivariate meta-analysis and review of contributing factors

OBJECTIVE

The purpose of this study was to analyze the factors that influence local recurrence after radiofrequency coagulation of liver tumors.

SUMMARY BACKGROUND DATA

Local recurrence rate varies widely between 2% and 60%. Apart from tumor size as an important risk factor for local recurrence, little is known about the impact of other factors.

METHODS

An exhaustive literature search was carried out for the period from January 1, 1990 to January 1, 2004. Only series with a minimal follow-up of 6 months and/or mean follow-up of 12 months were included. Univariate and multivariate meta-analyses were carried out.

RESULTS

Ninety-five independent series were included, allowing the analysis of the local recurrence rate of 5224 treated liver tumors. In a univariate analysis, tumor-dependent factors with significantly less local recurrences were: smaller size, neuroendocrine metastases, nonsubcapsular location, and location away from large vessels. Physician-dependent favorable factors were: surgical (open or laparoscopic) approach, vascular occlusion, general anesthesia, a 1-cm intentional margin, and a greater physician experience. In a multivariate analysis, significantly less local recurrences were observed for small size (P < 0.001) and a surgical (versus percutaneous) approach (P < 0.001).

CONCLUSIONS

Radiofrequency coagulation by laparoscopy or laparotomy results in superior local control, independent of tumor size. The percutaneous route should mainly be reserved for patients who cannot tolerate a laparoscopy or laparotomy. The short-term benefits of less invasiveness for the percutaneous route do not outweigh the longer-term higher risk of local recurrence.

Management of colorectal liver metastases

Hepatic metastases occur in 60% of patients following resection for colorectal cancer. Liver resection is the only curative option, with one third of resected patients alive at five years. In those developing recurrence in the liver following resection, further liver surgery may be curative, with similar 5 years survival rates of about 30%. Until recently surgery was feasible in only 15-25% of patients with colorectal liver metastases. New strategies, such as downstaging chemotherapy, portal vein embolization and two-stage hepatectomy, may increase the resectability rate by 15%. Earlier detection of liver metastases would increase resectability, although good follow-up trials are lacking. Once suspected, colorectal liver metastases are staged by spiral CT, CT portography and MRI, which have similar overall accuracies. Mortality following liver resection is less than 5% in major centres, with a morbidity rate of 20% to 50%. Prognostic scoring systems can be used to predict the likely cure rate with resection. Pulmonary metastases occur in 10-25% of patients with resected colorectal cancer, but are limited to the lung in only 2% of cases. In these selected cases surgery provides long-term survival in 20-40%, and repeat lung resection has shown similar rates. For patients with unresectable disease, chemotherapy and ablation techniques have been demonstrated to prolong survival, although chemotherapy alone has been shown to improve quality of life.

Complications of radiofrequency coagulation of liver tumours

BACKGROUND

Radiofrequency coagulation (RFC) is being promoted as a novel technique with a low morbidity rate in the treatment of liver tumours. The purpose of this study was to assess critically the complication rates of RFC in centres with both large and limited initial experience, and to establish causes and possible means of prevention and treatment.

METHODS

This is an exhaustive review of the world literature (articles and abstracts) up to 31 December 2001; 82 independent reports of RFC of liver tumours were analysed.

RESULTS

In total, 3670 patients were treated with percutaneous, laparoscopic or open RFC. The mortality rate was 0.5 per cent. Complications occurred in 8.9 per cent: abdominal bleeding in 1.6 per cent, abdominal infection in 1.1 per cent, biliary tract damage in 1.0 per cent, liver failure in 0.8 per cent, pulmonary complications in 0.8 per cent, dispersive pad skin burn in 0.6 per cent, hepatic vascular damage in 0.6 per cent, visceral damage in 0.5 per cent, cardiac complications in 0.4 per cent, myoglobinaemia or myoglobinuria in 0.2 per cent, renal failure in 0.1 per cent, tumour seeding in 0.2 per cent, coagulopathy in 0.2 per cent, and hormonal complications in 0.1 per cent. The complication rate was 7.2, 9.5, 9.9 and 31.8 per cent after a percutaneous, laparoscopic, simple open and combined open approach respectively. The mortality rate was 0.5, 0, 0 and 4.5 per cent respectively.

CONCLUSION

The morbidity and mortality of RFC, while low, is higher than previously assumed. With adequate knowledge, many complications are preventable.