Figure 3 depicts two instances in which stromal cells and immune cells were picked erroneously during tissue segmentation. Depending on the level of expression of the biomarker in non-tumor cells, this might lead to either overestimated or underestimated scores of PRMT6 in cancer cells. The second example is that some portions of the tumor tissues are not annotated as malignant epithelial cells because they have certain cell characteristics and a resemblance to stomal cells that were excluded during the training of the algorithm, as shown in Figure 4. The gene discussed is PRMT6; the disease is cancer.