Furthermore, we wish to examine the possible biological insights revealed by CeiTEA hierarchical clusters, for which we considered two datasets from cancerous tissues: a HER2‐positive breast cancer (BC) dataset comprising eight samples[42] and a pancreatic ductal adenocarcinoma (PDAC) dataset consisting of one sample.[18] Here, we demonstrate the robustness of CeiTEA in delineating tumor and tumor microenvironment (TME) regions, identifying subregions at the tumor‐TME boundary, and characterizing heterogeneity within both tumor and TME regions. The gene discussed is ERBB2; the disease is pancreatic ductal adenocarcinoma.