The invention relates to a stable water-in-oil emulsion composition containing: 20% to 40% (v/v) aqueous phase in the form of droplets and containing an anti-cancer agent； and 60% to 80% (v/v) lipid phase containing an iodized oil and at least one surfactant, having Formula (I), in a proportion, of surfactant mass relative to the total volume of the composition, of 0.3% to 5%, formula (I) for said surfactant being the following in which: s has a value of 0 or 1； m is a whole number from 2 to 30； R
