CD68 and neoplasm: Therefore, biomarkers enabling the early identification of chemorefractory patients (such as CD68 expression on macrophages,41 PD-1/PD-L1 expression on Hodgkin Reed-Sternberg cells or microenvironment cells,42 etc.), novel agents specifically targeting tumor cells along with the tumor microenvironment at the genetic or epigenetic level, as well as innovative therapeutic strategies are urgently needed for chemorefractory patients.