Percutaneous radiofrequency ablation (RFA) or robotic radiosurgery (RRS) for salvage treatment of colorectal liver metastases

Figures & data

Table I. Baseline characteristics.

	RRS (n = 30)	RFA (n = 30)	p
Gender - male - female	21 9	17 13	0.42*
Age, median (years) - range (years)	67.6 33–84	64.5 39–80	0.82^+
Total number of lesions evaluated (n)	35	35
Number of lesions per patient treated (n) - 1 - 2 - > 2	26 3 1	26 3 1	0.38^#
Number of treatments - second treatment of the same lesion	30 0	38 8	0.005*
Mean maximum diameter of lesions (mm) (range)	34 (7–53)	33 (8–53)	0.64^+
Palliative chemotherapy prior to local therapy n (%)	20 (67)	23 (77)	0.57*
Previous local therapy for liver metastases (other than RFA or RRS) n (%) - no - yes surgery SIRT/embolization/LITT	10 (33) 20 (67) 20 (67) 1 (3)	14 (47) 16 (53) 14 (47) 3 (10)	0.19* 0.61*
Median Time Since	35.0	24.8	0.88°
Diagnosis (Months, Range)	(6–96)	(2–138)

*Fisher's exact test; ⁺Mann-Whitney U-test; ^#χ²-test;°log-rank test significant p-values are bold typed.

Table II. Toxicity per treatment.

	RRS (n = 30)	RFA (n = 38)	p*
Bleeding (liver capsule)^# Blood bilirubin increased - due to procedure^$ - due to tumor progression^§ Nausea (any) - required treatment^§ Pain (required i.v. pain medication) Treatment required - analgesic sedation - general anaesthesia	1 (3) 1 (3) 1 (3) 2 (6.5) 0 0 0 0	2 (5) 2 (5) 1 (2.5) 1 (2.5) 5 (13) 3 (7.5) 2 (5) 34 (89) 4 (11)	0.84 0.84 0.99 0.45

All toxicities were graded according to the NCI CTCEA criteria version 3.0.

*Fisher's exact test; ^#all bleedings were minor bleedings to the liver capsule (NCI CTCAE 3.0 grade 1) requiring no further treatment; ^$grade 1; ^§grade 2.

Figure 1. Median local disease free survival (DFS) since treatment of liver metastases.

Figure 2. Median freedom from distant recurrence (FFDR) since treatment of liver metastases.

Table III. Treatment efficacy and survival times.

Lesions	RRS (n = 35)	RFA (n = 35)	p*
12-month local control rate (actuary)	85%	65%	0.09
24-month local control rate (actuary)	80%	61%	0.20
Patients	RRS (n = 30)	RFA (n = 30)	p*
Recurrence rate n (%)	20 (67)	19 (63)	0.99*
Local PFS months 95% CI	34.4 3.4–65.4	6.0 1.9–10.0	< 0.001°
FFDR months 95% CI	11.4 7.9–14.9	7.1 1.8–12.4	0.25°
OS 95% CI	34.4 19.9–48.9	52.3 31.1–73.6	0.06*

°log-rank test; *Fisher's exact test. FFDR, freedom from distant recurrence significant p-values are bold typed.