The safety and efficacy of microwave ablation for the treatment of CRC pulmonary metastases

Figures & data

Table 1. Patients characteristics.

Characteristic	n	%
Gender
Male	21	66
Female	11	34
Age
≤60	11	34
>60	21	66
Tumour size
≤3 cm	34	71
3–4 cm	8	17
4–5 cm	3	6
5–6 cm	3	6
DFI
≤12 m	14	44
>12 m	18	56
Index tumour site
Right upper lobe	9	19
Right middle lobe	12	25
Right lower lobe	7	15
Left upper lobe	14	29
Left lower lobe	6	12
Number of tumours
1 lesion	17	53
2 lesion	14	44
3 lesion	1	3
Primary tumour site
Rectum	19	59
Colon	13	41

Figure 1. Axial CT images of a 71-year-old man with a 2.2-cm metastatic tumour in right lung from primary colorectal cancer. (A) Image obtained immediately before MWA, (B) image obtained during MWA, (C) image obtained 3 months after ablation, (D) image obtained 1 year after MWA and (E) image obtained 3 years after MWA.

Table 2. Complications of percutaneous microwave ablations (48 sessions).

Complications	N (%)
Pneumothorax, asymptomatic (CTCAE Grade 1)	5 (10.4)
Pneumothorax, requiring drainage (CTCAE Grade 2)	1 (2.1)
Chest pain (CTCAE Grade 3)	3 (6.3)
Pleural effusion (CTCAE Grade 1)	1 (2.1)
Low fevers (CTCAE Grade 1)	4 (8.3)
Intrapulmonary bleeding (CTCAE Grade 1)	4 (8.3)

Figure 2. Kaplan–Meier estimates of the overall survival (OS) for 32 patients. The median survival time was 31 months (95% CI: 15.4–46.6).

Figure 3. Kaplan–Meier estimates of the overall survival (OS) for 32 patients divided into two subgroups according to tumour size (p = .007). Continuous line: patients with tumour ≤3 cm; dotted line, patients with tumour >3 cm.

Figure 4. Kaplan–Meier estimates of the overall survival (OS) for 32 patients divided into two subgroups according to DFI (p = .022). Continuous line: patients with DFI >12 months; dotted line, patients with DFI ≤12 months.

Figure 5. Kaplan–Meier estimates of the overall survival (OS) for 32 patients divided into two subgroups according to tumour number (p = .030). Continuous line: patients with one lesion; dotted line, patients with >1 lesions.

Table 3. Univariate and multivariate analyses of overall survival in patients.

		Univariate analysis		Multivariate analysis
Clinicopathological parameters	Comparison reference	Hazard ratio (95%CI)	p Value	Hazard ratio (95%CI)	p Value
Gender	Female/male	1.182 (0.390–3.584)	.768	0.360 (0.076–1.708)	.198
Age	≤60/>60	1.179 (0.424–3.277)	.752	1.300 (0.426–3.961)	.645
Tumour size	≤3 cm/>3 cm	0.164 (0.044–0.612)	.007	0.117 (0.020–0.682)	.017
Tumour-free interval	≤12 months/>12 months	3.718 (1.204–11.484)	.022	3.119 (0.779–12.479)	.108
Number of tumours	1 lesion/>1 lesion	0.291 (0.096–0.884)	.030	0.312 (0.081–1.199)	.090
Primary tumour site	Rectum/colon	0.688 (0.249–1.900)	.470	1.604 (0.396–6.494)	.508