A system and method are provided to automatically categorize biological and medical images. The new system and method can incorporate a machine learning classifier in which novel ideas are provided to guide the classifier to focus on regions of interest (ROI) within medical images for categorizing or classifying the images. The system and method can ignore regions when misleading structures exist. The detection and classification of one or more features of interest within a discriminative region of interest within an image are rendered invariant to differences in translation, orientation and/or scaling of the one or more features of interest within the medical image(s). The system and method allow a processor to more quickly, efficiently and accurately process and categorize medical images.