Quantitative dynamic contrast-enhanced ultrasound to predict intrahepatic recurrence of hepatocellular carcinoma after radiofrequency ablation: a cohort study

Figures & data

Figure 1. Flow chart of study participants.

Table 1. Characteristics of patients and HCC lesions.

Characteristics	All patients (n = 125)
Patient
Age,years (mean ± SD)	56.9 ± 9.6
Sex (n, %)
Female	26 (20.8%)
Male	99 (79.2%)
Etiology (n, %)
Hepatitis B virus	100 (80.0%)
Hepatitis C virus	23 (18.4%)
others	2 (1.6%)
Serum α-fetoprotein level, ng/mL (mean ± SD)	347.9 ± 871.7
Child–Pugh class (n, %)
Class A	111 (88.8%)
Class B	14 (11.2%)
HCC
No. of HCC lesions per patient (n, %)
1	113 (90.4%)
2	12 (9.6%)
Tumor size, mm (mean ± SD)	26.6 ± 8.7
Tumor location (n, %)
Left	22 (17.6%)
Right	99 (79.2%)
Left and right	4 (3.2%)
Proximity to important structures (n, %)
No	62 (49.6%)
Subcapsular	25 (20.0%)
Subphrenic	7 (5.6%)
Large vessel	22 (17.6%)
Gallbladder	9 (7.2%)
Diagnosis of HCC(n, %)
Imaging diagnosis	37 (29.6%)
Pathologic result	88 (70.4%)
Tumor stage(n, %)
Ia	63 (50.4%)
Ib	62 (49.6%)
Portal phase enhancement pattern
Hypoenhancement	60 (48.0%)
Isoenhancement	54 (43.2%)
Hyperenhancement	11 (8.8%)
AUC, %s (mean ± SD)	4561.1 ± 1716.2
MTT, s (mean ± SD)	61.1 ± 17.1
TTP, s (mean ± SD)	38.4 ± 8.9
PI, % (mean ± SD)	60.2 ± 11.6

Table 2. Potential risk factors affecting HCC recurrence after RFA.

Risk Factor	Univariate analysis			Multivariate analysis
	HR	95% CI	p Value	HR	95% CI	p value
Sex
Female	Ref
Male	0.6	0.3–1.1	0.104
Age	1.0	1.0–1.0	0.337
Etiology
Others	Ref
Hepatitis B virus	Inf	0.0–Inf	0.997
Hepatitis C virus	6238592.4	0.0–Inf	0.997
Serum α-fetoprotein level	1.0	1.0–1.0	0.328
Patient clinical stage
Ib	Ref
Ia	0.9	0.5–1.7	0.837
Child–Pugh class
B	Ref
A	1.6	0.6–4.5	0.362
No. of HCC lesions per patient
1	Ref
2	1.0	0.4–2.8	0.995
Tumor size(mm)	1.0	1.0–1.0	0.527
At-risk localization
No	Ref			Ref
Subcapsular	0.5	0.2–1.3	0.169	0.6	0.2–1.4	0.231
Subphrenic	1.5	0.5–5.0	0.508	0.8	0.2–3.0	0.774
Large vessel	0.3	0.1–0.9	0.040	0.5	0.2–1.4	0.181
Gallbladder	0.6	0.1–2.5	0.487	0.6	0.2–2.8	0.560
Tumor location
Left	Ref
Right	1.3	0.5–3.4	0.542
Left and right	4.1	0.8–21.2	0.093
Portal phase enhancement pattern
Hypoenhancement	Ref			Ref
Isoenhancement	0.5	0.3–1.0	0.048	0.9	0.4–1.9	0.747
Hyperenhancement	0.5	0.2–1.8	0.320	0.8	0.2–3.2	0.775
PI (%)	0.9	0.9–1.0	<0.001	0.9	0.9–1.0	0.009
TTP (s)	1.0	1.0–1.0	0.465
MTT (s)	1.0	1.0–1.0	0.177
AUC (%s)	1.0	1.0–1.0	0.006	1.0	1.0–1.0	0.335

Figure 2. ROC for PI measured by CEUS. The areas under the curve were 0.72 with a 95%CI for the area between 0.63 and 0.81.

Figure 3. Recurrence-free survival (RFS) of HCC patients according to different levels of PI. Patients with a PI 58.8% or lower had significantly poorer RFS than those with higher. (p < 0.0001).

Figure 4. The association between tumor size and risk for HCC Recurrence.

Table 3. Relationship between TTP and HCC recurrence after RFA in subgroup of tumor size.

Subgroup	n	Crude model			Model I			Model II
		HR	95%CI	p Value	HR	95%CI	p Value	HR	95%CI	p Value
Tumor size < 31	89	0.9827	0.9333–1.0037	0.0741	0.9848	0.9386–1.0124	0.1608	0.9726	0.9027–0.9999	0.0497
Tumor size ≥ 31	36	1.143	0.9865–1.1670	0.1003	1.1429	0.9827–1.1559	0.1237	1.1417	0.9748–1.1436	0.1973
p interaction		0.0195			0.0438			0.0316

Model 1 was a Cox proportional hazards model that was adjusted for sex and age. Model 2 was a Cox proportional hazards model that was adjusted for sex, age, etiology, number of lesions, tumor location, proximity to important structures, and serum α-fetoprotein level.

Figure 5. The hypothesis of overlapping ablation temperature conduction along the vessel to the residual tumor.