Adjuvant iodine-131-labeled lipiodol for prevention of intrahepatic recurrence of hepatocellular carcinoma: Which is the best treatment schedule?
Authors: Marco Tabone, Luca Vigano, Cristiana Laudi, Alessandro Ferrero, Riccardo Pellerito, Lorenzo Capussotti
Journal: Hepatology (2005)

We read with interest the paper by Boucher et al.1 on the improvement of disease-free survival (DFS) rate in patients with cirrhosis treated with adjuvant intra-arterial injection of iodine-131-labeled lipiodol (131-I-Lip) after resection for hepatocellular carcinoma (HCC). Since January 2002, we have treated with this adjuvant treatment 10 consecutive male patients with hepatitis C virus–related cirrhosis after radical liver resection for primary HCC. In contrast to other centers, according to the Italian radioprotection regulations, our protocol involved injection of a single dose of 1100 MBq, which allowed us to discharge patients after 5 days, when their radioactivity fell below 600 MBq. 131-I-Lip was injected into the hepatic artery within the sixth postoperative month. Patients' ages were 67 ± 8 years, 30% of them had a major liver resection, tumor size was 5.4 ± 1.8 cm, and microscopic vascular invasion was present in 50% and capsular invasion in 60%. The DFS rate of our 10 patients was compared with that of 20 patients who underwent liver resection before 2002 and were matched for sex, age, tumor size, and presence of vascular or capsular invasion. The Kaplan-Meier DFS rate was plotted and compared using the log-rank test. Figure 1 shows that our DFS rate is similar to that reported by Boucher et al., confirming the efficacy of this adjuvant therapy. Two-year disease-free survival rates in the two groups: treated versus controls When our experience is compared with other published data, we believe there are some unclear aspects which should be further investigated; the timing and dose of the injected radioactivity are still empirical and probably not yet optimal. In the pilot study by Lau et al.,2 1,850 MBq were injected within 6 weeks; in the study by Boucher et al., 2,400 MBq were injected within 3 months, and a third study by Partensky et al.,3 1,100 MBq were injected within 6 months and then repeated after 2 years in disease-free patients. Despite these differences in study protocols, it seems that the results of DFS are similar, suggesting the existence of a variable that has not been taken into account. It is conceivable this similarity may be due to the target volume of the remnant liver. It is likely the volume differed greatly between the various series of patients. Lau et al. report that 50% of patients underwent a major liver resection; such was the case in only 21% of the patients treated by Boucher et al., who used the highest injected activity, and conversely 75% of major resections were performed by Partensky et al., who used the lowest injected radioactivity. The delivered radiation dose (Gy) is known to be directly associated with the administered activity and inversely related to the volume of the target organ. Boucher et al. suggest that 2,400 MBq injected into the liver correspond to an estimated radiation dose of 5,000 cGy, but it is possible that the tumoricidal dose may be lower than this value. Thus, we suggest that the measure of the volume of the remnant liver targeted by the I-131-Lip should be included as a variable for results, tailoring the optimal dose for such an adjuvant therapy. We wish to thank Livia Ruffini for her assistance in allowing us to gain experience and thus making us comfortable with this technique. Marco Tabone*, Luca Vigano , Cristiana Laudi*, Alessandro Ferrero , Riccardo Pellerito , Lorenzo Capussotti , * Gastroenterology Division, Ospedale Mauriziano Umberto I, Turin, Italy, Surgical Oncology, I.R.C.C. Candiolo, Turin, Italy, Nuclear Medicine, Ospedale Mauriziano Umberto I, Turin, Italy.