The value of KRAS gene status in predicting local tumor progression of colorectal liver metastases following radiofrequency ablation

Abstract

Purpose: We investigated the relationships between KRAS gene status and local tumor progression (LTP) of colorectal liver metastases (CLMs) after treatment with percutaneous ultrasound-guided radiofrequency ablation (RFA). Materials and methods: Clinical and imaging data from 76 patients (154 lesions) with CLM who underwent percutaneous ultrasound-guided RFA and had KRAS gene test results between January 2012 and June 2016 were analyzed. The average lesion size was 2.3 ± 1.0 cm (range 0.9-5.7 cm); 38 cases (82 lesions) had wild-type KRAS, and 38 cases (72 lesions) had KRAS mutations. Results: The technique effectiveness was 98.1% (151/154), and the LTP rate was 18.2% (28/154) after RFA, which was performed between January 2012 and November 2017. The mean and median followup were 32.7 ± 2.5 and 32.0 ± 2.6 months (range 1-70 months), respectively. Cumulative LTP rates at 6 months and 1, 2 and 3 years post-RFA for all patients were 7.4, 14.5, 17.8 and 19.2%, respectively. The LTP rate for patients with mutant KRAS (27.8% [20/72]) was significantly higher than that in patients with wild-type KRAS (9.8% [8/82]; p ¼ .004). The cumulative LTP rates at 6 months and 1, 2 and 3 years post-RFA were 4.0, 11.1, 11.1 and 11.1%, respectively, for patients with wild-type KRAS and 11.2, 18.4, 25.2 and 36.2%, respectively, for patient with mutant KRAS (p ¼ .011). Univariate (p ¼ .011) and multivariate analyses (p ¼ .005) showed that KRAS genotype in liver metastases was predictive of LTP. Multivariate analysis also showed that ablation margin size (p< .001) and modified clinical risk score (CRS; p ¼ .033) were independent prognostic factors for LTP. Conclusions: KRAS gene status of liver metastatic lesions was associated with LTP rates after RFA of CLM. Ablation margin size and modified CRS were also independent prognostic factors for LTP.

Nomogram including chemotherapy response for prediction of intrahepatic progression-free survival in patients with colorectal liver metastasis through chemotherapy followed by radiofrequency ablation

“…mutation predicts positive resection margins and narrower resection margins in CRLM patients undergoing resection, suggesting different pathological and phenotypic features in patients with mutant and wild-type RAS [41]. Notably, the minimal ablation margin and RAS mutation status may interact as independent predictors of local tumor progression (LTP) following CRLM ablation [19][20][21].…”

“…And the relevant reports analyzed the factors affecting oncological outcomes after RFA of CRLM, such as RAS gene, ablation margin and modified clinical risk score (CRS), embryonic origin of the primary lesion, etc. [14][15][16][17][18][19][20][21][22][23][24][25]. Moreover, the previous studies also documented the favorable local control and long-term survival benefit for CRLM patients receiving RFA in addition to systemic chemotherapy [26][27][28].…”

Ten-Year Outcomes of Percutaneous Radiofrequency Ablation for Colorectal Cancer Liver Metastases in Perivascular vs. Non-Perivascular Locations: A Propensity-Score Matched Study

“…Real-time ultrasound systems, Aloka ultrasound systems (Alokaα-10, Tokyo, Japan) or GE systems (E9, GE, United States), were used for scanning the lesion with 3.5–5.0 MHz convex probes and needle-guide devices for RFA procedures. As previously described ( 20 ), one physician located and guided the lesions in real time, while another inserted the electrode needle into the tumor. Most RFA devices can create an ablation sphere with a maximum diameter of 5 cm in the liver, but when the tumor diameter exceeds 3 cm, a strategy involving multiple overlapping ablations is employed ( 21 ).…”

Genomics and Interventional Oncology in Metastatic Liver Cancer

“…43 Jiang et al also looked at KRAS status and determined that mutant status was associated with increased local tumor progression (mut 27.8% vs. wt 9.8%) after treatment with radiofrequency ablation of liver metastases. 44 Odisio et al demonstrated in a retrospective study of 92 patients with colorectal liver metastases that those patients with KRAS mutations treated with ablation had worse local tumor progression-free survival at 3-year posttreatment than the wild-type cohort (35% vs. 71%, p ¼ 0.001). 45 Calandri and Odisio also showed that RAS mutation status and ablation margins (> 10 mm) are indicative of local tumor progression-free survival.…”