To investigate the clinical efficacy of laparoscopic ultrasound-guided microwave ablation for the concurrent treatment of colorectal liver metastasis (CLM).

Clinical data of 66 patients with CLM who were admitted to Guangdong Provincial Hospital of Traditional Chinese Medicine between March 2012 and August 2016 were retrospectively analyzed. Among them, 39 cases were males and 27 were females, aged 38-81 years old with a median age of 56 years old. Primary diseases: 26 cases with rectal cancer, 18 with sigmoid colon cancer, 10 with ascending colon cancer, 7 with descending colon cancer and 5 with transverse colon cancer. The diameter of liver metastatic lesions was ≤3 cm and the quantity was ≤3, and no other distant metastasis was observed. The informed consents of all patients were obtained and the local ethical committee approval was received. All patients underwent laparoscopic ultrasound-guided microwave ablation for the treatment of liver metastases, and were transferred to concurrent laparoscopic resection of the primary lesions after no bleeding or bile leakage was confirmed. The clinical efficacy was observed during the postoperative follow-up.

The single ablation time was 5-10 min. The single complete ablation rate was 97%(64/66). One case of pleural effusion was observed after microwave ablation, and no ablation-related complications such as hepatic insufficiency, puncture point bleeding, bile leakage or bile duct stenosis were observed. The postoperative tumor recurrence rate was 44%(29/66) and the local recurrence rate of the ablation lesions was 9%(6/66). Eight patients respectively died at postoperative 11, 14, 15, 18, 22, 25, 28 and 33 months due to systemic metastasis with the mortality of 12%(8/66). Fifty-eight patients survived including 37 with tumor-free survival until the paper submission date.

Laparoscopic ultrasound-guided concurrent microwave ablation is a safe and efficacious treatment for CLM with the metastatic lesions ≤3 cm in diameter and ≤3 in quantity.