Long-term outcome of percutaneous radiofrequency ablation for periportal hepatocellular carcinoma: tumor recurrence or progression, survival and clinical significance

Abstract

Background/aim: Recent studies have suggested that periportal location of percutaneous radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) is considered as one of the independent risk factors for local tumor progression (LTP). However, the long-term therapeutic outcomes of percutaneous RFA as the first-line therapy for single periportal HCCand corresponding impacts on tumor recurrence or progression are still unclear.

Materials and methods: From February 2011 to October 2020, a total of 233 patients with single nodular HCC ≤ 5 cm who underwent RFA ± transarterial chemoembolization (TACE) as first-line therapy was enrolled and analyzed, including 56 patients in the periportal group and 177 patients in the nonperiportal group. The long-term therapeutic outcomes between the two groups were compared, risk factors of tumor recurrence or progression were evaluated.

Results: The LTP rates at 1, 3, and 5 years were significantly higher in the periportal group than those in the nonperiportal group (15.7, 33.7, and 46.9% vs 6.0, 15.7, and 28.7%, respectively, P = 0.0067). The 1-, 3- and 5-year overall survival (OS) rates in the periportal group were significantly worse than those in the nonperiportal group (81.3, 65.1 and 42.9% vs 99.3, 90.4 and 78.1%, respectively, P<0.0001). In the subgroup of single HCC ≤ 3 cm, patients with periportal HCC showed significantly worse LTP P = 0.0006) and OS (P<0.0001) after RFA than patients with single nonperiportal HCC; The univariate and multivariate analyses revealed that tumor size, periportal HCC and AFP ≥ 400ug/ml were independent prognostic factors for tumor progression after RFA. Furthermore, patients with single periportal HCC had significantly higher risk for IDR(P = 0.0012), PVTT(P<0.0001) and extrahepatic recurrence(P = 0.0010) after RFA than those patients with single nonperiportal HCC. .

Conclusion: The long-term therapeutic outcomes of RFA as the first-line therapy for single periportal HCC were worse than those for single nonperiportal HCC, an increased higher risk of tumor recurrence or progression after RFA was significantly associated with periportal HCC.

Keywords: Hepatocellular carcinoma (HCC); Periportal; Radiofrequency ablation (RFA); Therapeutic outcomes; Tumor progression; Tumor recurrence.

Fig. 1

The flow diagram showing exclusion criteria in patients with hepatocellular carcinoma (HCC) who underwent radiofrequency ablation (RFA) or transarterial chemoembolization (TACE) combined with RFA (TACE+RFA)

Fig. 2

Kaplan–Meier curve demonstrating local tumor progression and overall survival of HCCs after RFA in the periportal and nonperiportal groups

Fig. 3

Local tumor progression (LTP) after RFA for periportal HCC in a 57-year-old man. (A) Dynamic contrast-enhanced axial magnetic resonance (DCE-MRI) scan obtained showing a small HCC (arrow) in periportal location before RFA. (B) CT scan obtained during RFA showing a multitip expandable electrode adjacent to the portal vein (arrow). (C) CT scan obtained during portal venous phase 1 months after RFA showing the complete ablation zone (arrow) adjacent to the portal vein. (D) CT scan obtained during hepatic arterial phase and portal venous phase (not shown) 53 months after RFA showing the LTP, a small arterial enhancing nodule (arrows), with washout at portal venous phase. (E) CT scan obtained during portal venous phase 1 months after TACE+RFA showing the complete ablation zone (arrow) adjacent to the portal vein, “intratumoral lipiodol deposition” can be seen in the ablation zone. (F) CT scan obtained during portal venous phase 4 months after TACE+RFA showing the complete ablation zone (arrow) adjacent to the portal vein

Fig. 4

IDR with aggressive progression after RFA for periportal HCC in a 65-year-old man. (A) CT scan obtained during RFA showing a periportal HCC mass treated with TACE, and gasification (green arrowhead) was observed in the ablation zone during RFA. (B-C) CT scan obtained during the portal venous phase 1 month after RFA showing the complete ablation zone (arrow) adjacent to the portal vein (green arrowhead). (D) CT scan obtained during the portal venous phase 3 months after RFA showing multiple newly occurring small HCCs of similar size (arrow) surrounding the complete ablation zone (*)

Fig. 5

Extrahepatic recurrence with rapid progression after TACE+RFA for periportal HCC in a 61-year-old man. (A-B) DCE-MRI: hepatic arterial phase (A) and DWI (B) showing a small HCC (arrow) in the periportal location before TACE+RFA. (C-D) CT scan obtained during the portal venous phase 3 months after TACE+RFA showing the complete ablation zone (arrow) adjacent to the portal vein (arrowhead). (E) DWI scan obtained 6 months after TACE+RFA shows bone metastasis (arrow). (F) CT scan obtained 6 months after TACE+RFA showing thoracic wall metastases and multiple lung metastases (arrow). (G-I) CT scan obtained during the portal venous phase 12 months after TACE+RFA showing the complete ablation zone (arrow) adjacent to the portal vein accompanied by thoracic wall and lung metastases

Fig. 6

Residual tumor with rapid progression was observed in a 57-year-old man with periportal HCC, which showed direct invasion of the portal vein by residual tumor after RFA. (A) Dynamic contrast-enhanced axial magnetic resonance (DCE-MRI) scan obtained showing a small HCC (arrow) directly connected to the portal vein (arrowhead). (B) CT scan obtained during the portal venous phase 4 months after RFA showing the insufficient ablation margin (arrow) connected to the portal vein (arrowhead). (C)-(D) CT scan obtained during the hepatic arterial phase and portal venous phase 9 months after RFA showing local tumor progression accompanied by portal vein invasion (arrowhead)