Effect of a 188 Re-SSS lipiodol/131I-lipiodol mixture, 188 Re-SSS lipiodol alone or 131I-lipiodol alone on the survival of rats with hepatocellular carcinoma.
OBJECTIVE
It has been shown that the use of a cocktail of isotopes of different ranges of action leads to an increase in the effectiveness of metabolic radiotherapy. The purpose of the present study was to compare with a control group the effectiveness of three different treatments in rats bearing hepatocellular carcinoma (HCC), using (1) a mixture of lipiodol labelled with both I and Re, (2) lipiodol labelled with I alone and (3) lipiodol labelled with Re alone.


METHODS
Four groups were made up, each containing 14 rats with the N1-S1 tumour cell line. Group 1 received a mixture composed of 22 MBq of Re-SSS lipiodol and 7 MBq I-lipiodol. Group 2 received 14 MBq I-lipiodol. Group 3 received 44 MBq of Re-SSS lipiodol and group 4 acted as the control. The survival of the various groups was compared by a non-parametric test of log-rank, after a follow-up of 60, 180 and 273 days.


RESULTS
Compared with the controls, the rats treated with a mixture of Re-SSS lipiodol and I-lipiodol show an increase in survival, but only from day 60 onwards (P=0.05 at day 60 and 0.13 at days 180 and 273). For the rats treated with I-lipiodol, there was a highly significant increase in survival compared with the controls at day 60, day 180 and day 273 (P=0.03, 0.04 and 0.04, respectively). There is no significant increase in survival for the rats treated with Re-SSS lipiodol, irrespective of the follow-up duration (P=0.53 at day 60, 0.48 at day 180, and 0.59 at day 273).


CONCLUSIONS
In this study, I-lipiodol is the most effective treatment in HCC-bearing rats, because this is the only method that leads to a prolonged improvement of survival. These results cannot necessarily be extrapolated to humans because of the relatively small size and unifocal nature of the lesions in this study. It appears necessary to carry out a study in humans with larger tumours in order to compare these three treatments, particularly with a view to replacing I-labelled lipiodol by Re-labelled lipiodol. However, this study clearly demonstrated that, for small tumours, as in an adjuvant setting for example, I-labelled lipiodol should be a better option than Re-labelled lipiodol.
UPRES EA 3890/Service de Médecine Nucléaire, Centre Eugène Marquis, Rennes, France. etienne.garin@univ-rennes1.fr
Elienne
E
Garin
Hervé
H
Rakotonirina
Florence
F
Lejeune
Benoit
B
Denizot
Jerome
J
Roux
Nicolas
N
Noiret
Habiba
H
Mesbah
Jean-Yues
JY
Herry
Patrick
P
Bourguet
Jean-Jacques
JJ
Lejeune
D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000532:radiotherapy*; D004338:Drug Combinations; D005260:Female; D007457:Iodine Radioisotopes / Q000008:administration & dosage*; D007459:Iodized Oil / Q000008:administration & dosage*; D008113:Liver Neoplasms / Q000532:radiotherapy*; D009942:Organometallic Compounds / Q000008:administration & dosage*; D011379:Prognosis; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D051381:Rats; D017207:Rats, Sprague-Dawley; D016019:Survival Analysis; D015996:Survival Rate; D016896:Treatment Outcome
D004338:Drug Combinations; D007457:Iodine Radioisotopes; D009942:Organometallic Compounds; D019275:Radiopharmaceuticals; C494618:rhenium-SSS-lipiodol; D007459:Iodized Oil