The present invention provides an agent useful for the prevention of transition to surgical therapy for benign prostatic hyperplasia and the like. The present invention relates to a pharmaceutical composition for the prevention of transition to surgical therapy for benign prostatic hyperplasia, which comprises an indoline derivative represented by the following general formula (I) or a pharmaceutically acceptable salt thereof (in the formula, R represents an optionally substituted aliphatic acyl group, a hydroxyalkyl group, an aliphatic acyloxyalkyl group, a substituted lower alkyl group, an optionally substituted aromatic acyl group, a furoyl group, a pyridylcarbonyl group or the like； R1 represents a cyano group or a carbamoyl group； and R2 represents an optionally substituted lower alkyl group). [Chem.1] (See formula I)
