Clinical outcomes of percutaneous thermal ablation for pulmonary metastases from hepatocellular carcinoma: a retrospective study

Figures & data

Figure 1. (A) Chest CT image before ablation therapy shows a tumor with the maximum diameter of 15 mm. (B) CT image during MWA shows the antenna inserted into the tumor. (C) Follow-up CT scan after 1 month shows air inside the tumor and is evaluated as complete ablation. (D) Contrast enhanced MRI scan after 2 month shows marked involution of the tumor without contrast enhancement.

Table 1. Demographic and clinical characteristics of included patients.

Characteristics	Patients (n)	%
Total	39	100
Sex
Male	33	84.6
Female	6	15.4
Age [median (range)], years	59 (31–78)
Smoking
No	27	69.2
Yes	12	30.8
Alcohol
No	30	76.9
Yes	9	23.1
Diabetes
No	32	82.1
Yes	7	17.9
Liver cirrhosis
No	13	33.3
Yes	26	66.7
Treatment for primary HCC
Ablation	23	59
Resection	2	5.1
Liver transplantation	2	5.1
Other	12	30.8
Extent of PM
Unilateral	20	51.3
Bilateral	19	48.7
Number of PM [median (range)]	2 (1–5)
The maximum diameter of PM [median (range)], mm	15 (6.00–52.00)
Ablation modality for PM
RFA	22	56.4
MWA	8	20.5
Others	9	23
RFA + MWA	2	5.1
Cryoablation	7	17.9
Ablation session
1	23	59.0
2	11	28.2
3	5	12.8

PM: pulmonary metastases; RFA: radiofrequency ablation; MWA: microwave ablation.

Table 2. Tumor response at 1 month after ablation therapies.

	Number (%)	Unilateral PM, n (%)	Bilateral PM, n (%)	p Value
Local tumor response at 1month				0.49
Complete ablation	32 (84.2)	17 (89.5)	15 (78.9)
Incomplete ablation	1 (2.6)	0 (0.0)	1 (5.3)
Local progression	5 (13.2)	2 (10.5)	3 (15.8)

PM: pulmonary metastases.

Figure 2. The Kaplan–Meier estimates of survival for all included patients. (A) The OS rates of all patients with pulmonary metastases (PM) from hepatocellular carcinoma (HCC) treated with thermal ablation. (B) The local progression-free survival rates of all patients with PM from HCC treated with thermal ablation.

Figure 3. The Kaplan–Meier estimates of survival for patients in different subgroups. (A) and (C): The overall survival (OS) rates and local progression-free survival (LTPFS) rates of patients with ≤2 or >2 PMs. (B) and (D): the OS rates and LTPFS rates of patients with unilateral or bilateral PM.

Table 3. Subgroup analysis for overall survival rate, local tumor progression-free survival rate and complete response rate.

Subgroup	Number	3-year OS,%	5-year OS,%	p Value	3-year LTPFS,%	5-year LTPFS,%	p Value	CR (1 month), %	p Value
ALL		58.0	30.9		34.2	22.8		84.2
Number of lesions				0.098			0.185		0.682
≤2	23	35.2	35.2		21.2	NA		86.4
>2	16	85.6	32.1		57.0	28.5		81.3
Extent of lung metastases				0.298			0.401		0.660
Unilateral	20	65.8	65.8		39.7	NA		89.5
Bilateral	19	50.8	19.1		29.3	14.6		78.9
Ablation technique				0.630			0.068		0.156
RFA	22	49.9	NA		31.	NA		90.9
MWA	8	NA	NA		NA	NA		87.5
Other
RFA + MWA	2	100	NA		NA	NA		66.7
Cryoablation	7	75.0	50		50.0	33.3		50.0

NA: not available; RFA: radiofrequency ablation; MWA: microwave ablation; CR: complete ablation.

Table 4. Univariate and multivariate analysis of all included patients for overall survival in Cox proportional hazard model.

Variation	Univariate		Multivariate
	HR (95%CI)	p Value	HR (95%CI)	p Value
Categorical variables
Gender	1.274 (0.272–5.963)	0.758
Diabetes	1.042 (0.312–3.476)	0.947
Hypertension	0.855 (0.185–3.966)	0.842
Alcohol	0.570 (0.124–2.616)	0.470	2.277 (0.465–11.148)	0.310
Smoking	0.814 (0.239–2.766)	0.741
Treatment for primary HCC	0.751 (0.510–1.106)	0.147	0.923 (0.590–1.445)	0.727
Ablation modality for PM	0.740 (0.375–1.461)	0.386	0.769 (0.349–1.695)	0.515
Extend of PM	1.893 (0.559–6.409)	0.305	0.197 (0.043–0.890)	0.035
Liver cirrhosis	1.042 (0.312–3.476)	0.947
Age	0.996 (0.946–1.049)	0.890
Preoperative AFP	1.00006 (0.99997–1.0001)	0.223	1.00007 (0.99995–1.0002)	0.233
Ablation session	0.892 (0.434–1.833)	0.755
Number of PM	0.802 (0.533–1.209)	0.292	0.555 (0.311–0.991)	0.047
Maximum diameter of PM	0.962 (0.883–1.047)	0.367	0.979 (0.891–1.075)	0.659
Ablation margin	0.524 (0.110–2.494)	0.417	0.838 (0.142–4.928)	0.845

HCC: hepatocellular carcinoma; AFP: alpha-fetoprotein; PM: pulmonary metastases.