Recurrence-free Survival of Patients with Liver Metastases from Colorectal Cancer who Underwent Radiofrequency Treatment of Surgical Margins

Background: Liver resection remains the gold standard for the treatment of both primary and metastatic liver tumors. The goal of liver resection is to remove all macroscopic disease with negative resection margins and leave sufficient functioning liver. In patients with colorectal liver metastases several factors have found to be independent predictors of survival, such as intraoperative blood transfusion requirement, nodal status of the primary tumor, presence of multiple satellite nodules, and cancer involved surgical resection margin. In some studies a subcentimeter resection margin is linked to a greater liver recurrence even though it should not preclude resection, and it has been shown that repeat hepatectomy for recurrent colorectal metastases can prolong survival in selected patients and has low operative risk.Moreover, good survival rates have been described in some groups of patients with less than 1 cm clearance. Several investigations have demonstrated that the risk of recurrence increases significantly with the size of liver metastases, especially when the size is >5 cm. This risk is attributed to the increased invasiveness of larger masses, as shown by a higher incidence of intrahepatic metastasis and portal venous invasion for large metastases. The aim of the study was to evaluate the recurrence-free survival in patients with positive margins after hepatic resection of liver metastases (LM) from colorectal cancer, followed by radiofrequency ablation (RFA) of surgical margins. Patients and Methods: Data regarding a group of six patients (4 men and 2 women, aged 67.7±18.2 years), with positive margins at final pathology of resected LM were retrospectively analyzed. Surgery included 2 wedge resections, 2 segmentectomies and 2 pluri-segmentectomies. All patients were treated with RFA of surgical margins, and all of them received adjuvant chemotherapy. Final pathology found positive margins in all patients. Results: All patients are alive at the follow-up of 24.2±2.6 months. None of them had liver recurrence, but a distant recurrence was found in two (lung and lymph nodes) after 11 and 6 months, respectively. Thus, local recurrence-free survival was 24.2±2.6 months, while systemic recurrence-free survival was 18±16.4 months. Main biochemical findings on day 0, 1, and 5 were: (1) haemoglobin 12,7±0.9, 10.1±0.9, 10±0.6 g/dL, (2) alanine-aminotransferase 33.3±30.8, 212±125.4, 51.7±36.2 U/L, (3) albumin 4±0.3, 2.8±0.4, 3.0±0.2 g/dL, (4) international normalized ratio (INR) 1.2±0.1, 1.3±0.1, 1.1±0.1. Conclusions: The role of surgical margin after liver resection for LM is controversial. It has been suggested that margin status is an independent predictor of long-term outcome after hepatic resection for LM. Thus, in patients undergoing hepatic resection for LM a >1 cm margin should be attempted, whenever possible. The use of ultrasonic surgical aspirator achieves an additional resection margin of approximately 5 mm, while with RFA more liver parenchyma could be preserved, adding approximately 10 mm of clear margin. Interestingly, RFA treatment seems to influence only the local recurrence. These preliminary data suggest that the technique is safe, and may be considered after liver resection for LM.