This paper studies the use of total curvature for shape discrimination of objects via profiles of their planar sections (not assumed star shaped). Methods of estimating total curvature from observation of a finite number of points on the boundary of the object are investigated, including a simple discrete approximation method and various interpolation methods. Total curvature is capable of revealing shape differences on a local scale, as demonstrated by the analysis of two data sets of malignant and normal or benign tumor cell nuclear profiles.