Accuracy of lobule detection and PR nuclear positivity in a test case. A Accuracy of lobule detection is best at intermediate distance to the tumor (Tu). Note the false positive structures (circled in red, manually excluded from analysis), initially misclassified as lobules within a zone of inflammatory tumor microenvironment. B Detail showing the effect of inaccuracies in tumor classification. Most of the tumor borders are correctly detected (*), but in a small stretch the algorithm has classified too much of the surrounding stroma as tumor area (**). As a consequence, the distance to tumor borders may be slightly underestimated in such regions. C Upsampling of lobule areas as individual regions of interest within the workflow reduces the areas subjected to subcellular analysis of nuclei at high resolution.