Original Article Dig Dis 2014;32:670–677 DOI: 10.1159/000367999
Radiofrequency Ablation for Hepatocellular Carcinoma Measuring 2 cm or Smaller: Results and Risk Factors for Local Recurrence Masashi Kono a Tatsuo Inoue a Masatoshi Kudo a Hirokazu Chishina a Tadaaki Arizumi a Masahiro Takita a Satoshi Kitai a Norihisa Yada a Satoru Hagiwara a Yasunori Minami a Kazuomi Ueshima a Naoshi Nishida a Takamichi Murakami b a
Division of Gastroenterology and Hepatology, Department of Internal Medicine, and b Department of Radiology, Kinki University School of Medicine, Osaka-Sayama, Japan
Abstract Objective: The purpose of this study was to evaluate the risk factors for local recurrence with radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) measuring ≤2 cm. Methods: This study involved 234 patients with 274 HCCs measuring ≤2 cm who had undergone RFA as the initial treatment. The mean tumor diameter was 1.478 cm. The median follow-up period was 829 days. We evaluated the postRFA cumulative local recurrence rate and analyzed the risk factors contributing to clinical outcomes. Results: Cumulative local recurrence rates were 9, 19 and 19% at 1, 2 and 3 years, respectively. Among the 145 cases with a complete safety margin (SM) after RFA, only 4 developed local tumor recurrence and the cumulative rates of local tumor recurrence at 1, 2 and 3 years were 2, 3 and 3%, respectively. Among the 129 cases with incomplete SM, local tumor recurrence developed in 34 and the cumulative rates of local tumor progression at 1, 2 and 3 years were 14, 36 and 36%,
© 2014 S. Karger AG, Basel 0257–2753/14/0326–0670$39.50/0 E-Mail [email protected] www.karger.com/ddi
respectively. In multivariate analysis, significant risk factors were tumor location (liver surface), irregular gross type and SM 2 cm in diameter (n = 151, 126 patients)
Multiple HCCs (n = 71, 31 patients)
Fig. 1. Study design.
In addition, RFA is much less invasive and associated with lower mortality and shorter hospital stays than liver resection [7]. Small solitary HCC lesions 2 cm; thus, we investigated 234 patients with 274 HCCs measuring ≤2 cm (fig. 1). Of these 274 HCCs, 227 received RFA alone, 41 received transcatheter arterial chemoembolization (TACE) and 6 received transcatheter arterial infusion before RFA.
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Patients and Methods
a
b
c
d
e
f
g
h
i
68-year-old woman diagnosed as SN type HCC by CECT. HCC location S8, not in the liver surface area (arrow). b After RFA, we assessed the treatment effect as SM-negative on CECT. Severe pain and high fever continued after RFA, so additional RFA was not performed. c Arterial phase of CECT, 9 months after RFA, showed local recurrence at the periphery of the ablation zone (arrow). d A 70-year-old man diagnosed as non-SN type HCC, not located in the liver surface area, on CECT (arrow). e Two days after ablation,
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Dig Dis 2014;32:670–677 DOI: 10.1159/000367999
we assessed the treatment effect as SM-negative on CECT. As the vessel was situated near the ablation area, we decided it would be too difficult to perform additional RFA. f Arterial phase of CECT, 11 months after RFA, showed local recurrence at the periphery of the ablation zone (arrow). g A 69-year-old man diagnosed as SN type HCC by CECT located on S7 liver surface area (arrow). h After ablation, we assessed the treatment effect as SM-positive on CECT. i Arterial phase of CECT, 7 months after RFA, showed local recurrence at the peripheral ablation zone (arrow).
Kono et al.
Downloaded by: Siriraj Medical Library, Mahidol University 202.28.191.34 - 1/25/2015 6:31:37 PM
Fig. 2. Representative cases of local recurrence after RFA. a A
Definition of Safety Ablative Margin, Gross Type and HCC Location Complete response was defined as the absence of enhanced tumoral areas reflecting complete tissue necrosis as assessed by follow-up imaging modalities within 1 week after RFA. We judged that a safety margin (SM) was positive if there was a complete circumferential ablative margin of ≥5 mm, based on a comparison of CT or MRI images obtained before and after RFA in a side-by-side manner. Conversely, a negative SM was a circumferential ablative margin of
Radiofrequency Ablation for Hepatocellular Carcinoma Measuring 2 cm or Smaller: Results and Risk Factors for Local Recurrence Masashi Kono a Tatsuo Inoue a Masatoshi Kudo a Hirokazu Chishina a Tadaaki Arizumi a Masahiro Takita a Satoshi Kitai a Norihisa Yada a Satoru Hagiwara a Yasunori Minami a Kazuomi Ueshima a Naoshi Nishida a Takamichi Murakami b a
Division of Gastroenterology and Hepatology, Department of Internal Medicine, and b Department of Radiology, Kinki University School of Medicine, Osaka-Sayama, Japan
Abstract Objective: The purpose of this study was to evaluate the risk factors for local recurrence with radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) measuring ≤2 cm. Methods: This study involved 234 patients with 274 HCCs measuring ≤2 cm who had undergone RFA as the initial treatment. The mean tumor diameter was 1.478 cm. The median follow-up period was 829 days. We evaluated the postRFA cumulative local recurrence rate and analyzed the risk factors contributing to clinical outcomes. Results: Cumulative local recurrence rates were 9, 19 and 19% at 1, 2 and 3 years, respectively. Among the 145 cases with a complete safety margin (SM) after RFA, only 4 developed local tumor recurrence and the cumulative rates of local tumor recurrence at 1, 2 and 3 years were 2, 3 and 3%, respectively. Among the 129 cases with incomplete SM, local tumor recurrence developed in 34 and the cumulative rates of local tumor progression at 1, 2 and 3 years were 14, 36 and 36%,
© 2014 S. Karger AG, Basel 0257–2753/14/0326–0670$39.50/0 E-Mail [email protected] www.karger.com/ddi
respectively. In multivariate analysis, significant risk factors were tumor location (liver surface), irregular gross type and SM 2 cm in diameter (n = 151, 126 patients)
Multiple HCCs (n = 71, 31 patients)
Fig. 1. Study design.
In addition, RFA is much less invasive and associated with lower mortality and shorter hospital stays than liver resection [7]. Small solitary HCC lesions 2 cm; thus, we investigated 234 patients with 274 HCCs measuring ≤2 cm (fig. 1). Of these 274 HCCs, 227 received RFA alone, 41 received transcatheter arterial chemoembolization (TACE) and 6 received transcatheter arterial infusion before RFA.
671
Downloaded by: Siriraj Medical Library, Mahidol University 202.28.191.34 - 1/25/2015 6:31:37 PM
Patients and Methods
a
b
c
d
e
f
g
h
i
68-year-old woman diagnosed as SN type HCC by CECT. HCC location S8, not in the liver surface area (arrow). b After RFA, we assessed the treatment effect as SM-negative on CECT. Severe pain and high fever continued after RFA, so additional RFA was not performed. c Arterial phase of CECT, 9 months after RFA, showed local recurrence at the periphery of the ablation zone (arrow). d A 70-year-old man diagnosed as non-SN type HCC, not located in the liver surface area, on CECT (arrow). e Two days after ablation,
672
Dig Dis 2014;32:670–677 DOI: 10.1159/000367999
we assessed the treatment effect as SM-negative on CECT. As the vessel was situated near the ablation area, we decided it would be too difficult to perform additional RFA. f Arterial phase of CECT, 11 months after RFA, showed local recurrence at the periphery of the ablation zone (arrow). g A 69-year-old man diagnosed as SN type HCC by CECT located on S7 liver surface area (arrow). h After ablation, we assessed the treatment effect as SM-positive on CECT. i Arterial phase of CECT, 7 months after RFA, showed local recurrence at the peripheral ablation zone (arrow).
Kono et al.
Downloaded by: Siriraj Medical Library, Mahidol University 202.28.191.34 - 1/25/2015 6:31:37 PM
Fig. 2. Representative cases of local recurrence after RFA. a A
Definition of Safety Ablative Margin, Gross Type and HCC Location Complete response was defined as the absence of enhanced tumoral areas reflecting complete tissue necrosis as assessed by follow-up imaging modalities within 1 week after RFA. We judged that a safety margin (SM) was positive if there was a complete circumferential ablative margin of ≥5 mm, based on a comparison of CT or MRI images obtained before and after RFA in a side-by-side manner. Conversely, a negative SM was a circumferential ablative margin of
