Microwave ablation for colorectal cancer metastasis to the liver: a single-center retrospective analysis

Abstract

The purpose of this study is to evaluate the safety and intermediate-term efficacy of percutaneous microwave (MW) ablation for the treatment of colorectal liver metastases (CRLM) at a single institution. Methods:A retrospective review was performed of all CRLM treated with MW ablation from 3/2011 to 7/2020 (102 tumors; 72 procedures; 57 patients). Mean age was 60 years (range, 36-88) and mean tumor size was 1.8 cm (range, 0.5-5.0 cm). The patient population included 19 patients with extra-hepatic disease. Chemotherapy (pre-and/or post-ablation) was given in 98% of patients. Forty-five sessions were preceded by other focal CRLM treatments including resection, ablation, radiation, and radioembolization. Kaplan-Meier curves were used to estimate local tumor progression-free survival (LTPFS), disease-free survival (DFS), and overall survival (OS) and multivariate analysis (Cox Proportional Hazards model) was used to test predictors of OS. Results:Technical success (complete ablation) was 100% and median follow-up was 42 months (range, 1-112). There was a 4% major complication rate and an overall complication rate of 8%. Local tumor progression (LTP) rate during the entire study period was 4/98 (4%), in which 2 were retreated with MW ablation for a secondary LTP-rate of 2%. LTP-free survival at 1, 3, and 5 years was 93%, 58%, and 39% and median LTP-free survival was 48 months. OS at 1, 3, and 5 years was 96%, 66%, 47% and median OS was 52 months. There were no statistically significant predictors of OS. Conclusions:MW ablation of hepatic colorectal liver metastases appears safe with excellent local tumor control and prolonged survival compared to historical controls in selected patients. Further comparative studies with other local treatment strategies appear indicated.

Evidence on percutaneous radiofrequency and microwave ablation for liver metastases over the last decade

“…of patients No. of tumors Size of Tumors [mm] Follow-up [months] Local tumor control [%] Overall survival [months] Overall survival [%] (Disease- or Progression-free survival [%]) 1-year 2-year 3-year 4-year 5-year Cheng et al [ 11 ] 2021 RFA 68 – 29 (median) 59.8 (median) 47.1 53.4 (median) 88.1 – 66.9 – 64.5 Knott et al [ 12 ] 2021 MWA 57 102 18 (mean) 42 (median) 96 52 (median) 96 (93) – 66 (58) – 47 (39) Fan et al [ 13 ] 2021 RFA 199 402 16 (mean) 23 (median) 62.9 Subcapsular 46 (median) 96.1 – 66 – 44.2 non-subcapsular 60 (median) Kurilova et al [ …”

“…Cheng et al reported the outcome of RFA using a multielectrode radiofrequency switching controller for resectable metachronous CRLM; the 5-year survival and median OS were 50.7% and 53.4 months, respectively [11]. Table 2 presents the outcomes of RFA and MWA for CRLM including the 5-year OS rates [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27]. In the listed studies, 5-year OS following ablation ranged from 21 to 65%.…”

Surgical and Interventional Management of Liver Metastasis

“…26 A systematic review of the literature on RFA for CRC liver metastases reported a wide range of 5-year survival (14–55%) and local recurrence rates (3.6–60%). 27…”

Percutaneous microwave ablation‑induced hepatic artery‑pulmonary artery fistula: A rare case report

“…Microwave ablation (MWA) is a promising non-vascular interventional technique, with clear efficacy in local control. For the treatment of small primary and secondary hepatic tumors (<3 cm), MWA may be comparable to surgical resection (1)(2)(3)(4). Furthermore, numerous clinical trials have indicated that trans-arterial chemoembolization (TACE) combined with MWA may significantly improve the rate of complete necrosis of tumors and prolong the survival of patients (5,6).…”