A method for determining the location, shape and orientation of a tumor in a medical image includes finding a plurality of spatial extrema .mu. of a D-dimensional spatial signal f for a set of bandwidths H by performing mean shift-based gradient-ascent iterations for a set of bandwidths H and then determining a D-dimensional spread and orientation of the signal about each extrema .mu. by estimating a covariance .SIGMA. of the signal f for each extrema .mu.. The optimal estimate of .mu. and .SIGMA. is determined by performing a Jensen-Shannon divergence on the full set of .mu. and .SIGMA..