Survival
Median survival was 72 weeks,
with 1,
2,
and 3-year survival 90.3%,
72.3% and 65% respectively.
Patients with tumours >30mm had a mean survival of 96 weeks,
compared to 180 weeks in smaller lesions (p=0.009) (figure 1).
Patients who received pre-RFA chemotherapy had mean survival of 180 weeks,
compared to 101 weeks in those who had not (p=0.033) (figure 2).
Patients with maximum tumour diameter less than 30mm in whom lesions were located distant to both hepatic vessels and biliary structures had a mean survival of 177 weeks compared to 114 weeks in patients with a maximum tumour diameter greater than 30mm or lesions located close to vascular (p = 0.015) (figure 3).
The following variables were not statistically significant: initial number of tumours ablated; total number of tumours ablated; liver resection; total number of RFA procedures performed; the presence of additional site metastases; the primary tumour site (table 1).
Tumour Recurrence
47% of lesions developed recurrence,
with mean and median time to recurrence 24 and 21 weeks respectively (Images 1a-d).
17% of recurrences occurred when the lesion was abutting a major blood vessel; a further 8% were close to biliary structures.
Five (21%) of the recurring lesions were large.
As a result,
the aim of RFA was to achieve de-bulking only.
29% of recurring lesions underwent repeat RFA with secondary effectiveness rate of 58.8% (30 of 51 lesions without tumour progression at the end of follow-up with the remaining demonstrating evidence of relapse).
Complications
The significant complication rate was 11%.
Three patients developed bleeding with formation of a sub-capsular collection.
One patient developed a sub-phrenic collection with associated portal vein thrombosis
Another patient sustained significant thermal damage to the right hemi-diaphragm with resultant right lower lobe consolidation (Image 2).
The thirty day mortality following RFA was 0%.