Prognostic value of 18F-fluorodeoxyglucose positron emission tomography in patients with small hepatocellular carcinoma treated by radiofrequency ablation
Yoshiyuki Ida, Hideyuki Tamai, Naoki Shingaki, Ryo Shimizu, Shuya Maeshima, Takao Maekita, Mikitaka Iguchi, Masaki Terada, Masayuki Kitano
Abstract
Abstract Background 18 F-fluorodeoxyglucose ( 18 F-FDG) uptake in hepatocellular carcinoma (HCC) is significantly associated with early recurrence and survival after curative surgical resection. However, there are no reports regarding the relationship between 18 F-FDG uptake and outcomes after radiofrequency ablation (RFA). A prospective cohort study was conducted to evaluate the prognostic value of 18 F-FDG positron emission tomography (PET) in HCC patients after RFA. Methods A total of 121 consecutive patients with primary HCC (≤3 tumors, of diameter ≤ 3 cm) without vascular invasion on imaging were examined by 18 F-FDG-PET computed tomography prior to RFA. An HCC with a component of 18 F-FDG uptake visibly stronger than that of surrounding liver was defined as 18 F-FDG-PET positive. Results The median follow-up period was 1267 days. There were 110 18 F-FDG-PET negative and 11 positive tumors. The cumulative 1-year recurrence rates in the 18 F-FDG negative and positive groups were 30 and 64% ( P = 0.017), respectively, and cumulative 1-year metastatic recurrence rates were 6 and 36% ( P < 0.001), respectively. The cumulative 5-year survival rates were 88 and 22% ( P < 0.001), respectively. Multivariate analysis revealed 18 F-FDG-PET positivity and tumor size as independent factors related to metastatic recurrence and survival after RFA. Conclusions 18 F-FDG-PET positivity was significantly associated with outcomes after RFA. RFA should not be readily selected as the first-line treatment for small HCC that includes a component of visually strong 18 F-FDG uptake.