In the high PCDI score group, we observed a conspicuous immunosuppressive microenvironment characterized by enhanced immunosuppressive cell infiltration, including M2 macrophages, Treg cells, and neutrophils, along with impaired antitumor immune functions such as IFN response and T-cell co-stimulation, resembling the immunological features of cluster A. In addition, we discerned a significant positive correlation between stemness score and PCDI score, aligning with a previous study associating tumor stem cell status with immunological characteristics in solid tumors. The gene discussed is IFNA1; the disease is neoplasm.