12563 878Disclosed is an antitumor agent which uses a compound represented by formula (I) or a pharmacologically acceptable salt thereof in combination with a compound represented by formula (II) or a pharmacologically acceptable salt thereof. The antitumor agent exhibits remarkable antitumor effect in comparison to the cases where each one of the above mentioned compounds is used alone. In addition the antitumor agent exhibits antitumor effect on various kinds of cancer. (In the formulae R represents an azetidinyl group or the like R to R each represents a hydrogen atom or a halogen atom R represents a C cycloalkyl group or the like R represents a hydrogen atom or the like and R represents a halogen atom or the like.)
