Ultrasound-guided hydrodissection for assisting percutaneous microwave ablation of renal cell carcinomas adjacent to intestinal tracts: a preliminary clinical study

Figures & data

Table 1. Clinical features of the patients and tumours.

Variables	Data
Patient analysis
No. of patients	24
Gender (male/female)	18/6
Mean age ± SD (range, years)	68.3 ± 9.8 (51–85)
No. of patients with one ablated tumour (%)	23 (95.8%)
No. of patients with two ablated tumours (%)	1 (4.2%)
Tumor analysis
No. of tumours	25
Mean diameter ± SD (range) (cm)	3.80 ± 1.60 (0.9–7.5)
No. of clear cell carcinomas (%)	24 (96.0%)
No. of papillary cell carcinomas (%)	1 (4.0%)
Mean follow-up ± SD (range) (months)	14.9 ± 10.1 (1–30)

Table 2. Parameters of the hydrodissection and ablation procedure.

Variables	Means ± SD (range)
Volume of saline injection	631.1 ± 384.7 (150–1570)
Ablation time (s)	1189.6 ± 661.0 (300–2680)
Ablation power (W)	52.4 ± 4.4 (50–60)
Ablation energy (kJ)	62.8 ± 36.1 (15–158)
Ablation session	1.1 ± 0.3 (1–2)
Antenna insertion	3.1 ± 1.6 (1–7)

Figure 1. A 67-year-old man with histopathologically a proven clear cell carcinoma renal tumour on the right side. (A) Transverse contrast enhanced MRI reveals a 1.3-cm hypoenhancement tumour (arrow) located on the ventral side of the right kidney adjacent to the colon (curve arrow) before the MWA. (B) After the saline injection hydrodissection (solid triangle), the colon (curve arrow) is successfully separated from the renal tumour (arrow) on US imaging. (C) Transverse contrast-enhanced MRI 3 months after the MWA reveals that the tumour adjacent to the colon (curved arrow) is completely ablated (arrow). (D) Transverse contrast-enhanced MRI 6 months after the MWA reveals the completely ablated tumour (arrow) adjacent to the colon (curved arrow) shrinkage.

Table 3. Complications and side effects.

Variables	No. (% of patients)
Major complications
Hydrothorax with catheter drainage	1 (4.2%)
Minor complications
Hemoglobinuria	1 (4.2%)
Gross haematuria	1 (4.2%)
Microscopic haematuria	3 (12.5%)
Side effects
Abdominal distention	3 (12.5%)
Post-ablation syndrome (fever)	7 (29.2%)
Mild pain	2 (8.3%)

Figure 2. The changes in renal function. (A) There was no significant difference in the mean serum creatinine level 1 day after the MWA (p = 0.384) and at the last follow-up (p = 0.500) compared with that prior to the MWA. (B) No significant differences in the mean blood urea nitrogen were observed 1 day after the MWA (p = 0.075) and at the last follow-up (p = 0.650) compared with that before the MWA.