Technical and clinical outcomes of microwave ablation for HCC: a single-center retrospective analysis of percutaneous ultrasound-guided, intraoperative ultrasound-guided and CT hepatic arteriography-guided approaches.

[OBJECTIVES] To compare technical/clinical outcomes of microwave ablations (MWA) for hepatocellular carcinoma (HCC) performed with percutaneous ultrasound (US)-guidance, intraoperative ultrasound (IOUS)-guidance or CT hepatic arteriography (CTHA)-guidance.

[MATERIALS & METHODS] This single-center retrospective study included 111 non-randomized patients (M:F = 91:20, median age 66y, range 51-86) with 200 HCCs (BCLC 0-A-B), treated with 136 MWA procedures (66 US-guided, 36 IOUS-guided, 34 CTHA-guided) between July 1, 2017, and January 31, 2025, with at least 6 months of clinical and CT/MRI follow-up. We evaluated patients' and nodules' characteristics, radicality (absent residual tumor at follow-up), local tumor progression, additional treatments, adverse events (CIRSE classification) and mortality. For patients undergoing multiple ablations, clinical outcomes were analyzed in relation to the first treatment.

[RESULTS] One nodule was ablated in 94/136 (69.1%) procedures, 2 nodules in 25/136 (18.4%), > 3 in 17/136 (12.5%). We encountered 13 adverse events, with the highest severity in IOUS-guided MWAs (1 grade 3, 2 grade 6). Fifty-eight patients (52.3%) progressed in other segments, subsequent treatments were performed in 57/111 (51.3%) patients and 28/111 (25.2%) died during follow-up. IOUS-guided MWA was associated with the highest radicality rate (56/60, 93.3%, p = 0.04) compared to CTHA-guided (45/51, 88.2%) and US-guided (72/89, 80.9%) ablations. Treating multiple nodules increased complication risk (p = 0.003), impacting on radicality (p = 0.032). No differences were found for overall survival (p = 0.07) or progression-free survival (p = 0.584) among the techniques.

[CONCLUSIONS] IOUS-guidance for HCC ablation provided a higher radicality rate compared to CTHA- and ultrasound-guidance techniques, but carried a higher risk of severe complications.