Méhes G, et al. - In this study, researchers assessed the impact of hypoxia related carbonic anhydrase IX and XII isoenzyme expression as a basic adaptive mechanism to neutralize intracellular acidosis in classical Hodgkin's lymphoma (cHL). For necrosis, CAIX and CAXII expression and cell proliferation, 81 primary biopsies and 15 relapsed tissue samples diagnosed with cHL were analyzed to compare histological and functional data related to hypoxia with survival characteristics. Findings suggested a strong association of the CAIX+ phenotype with lymphocyte depletion and nodular sclerosis subtypes. According to outcomes, hypoxic adaptation related to stress, highlighted by CAIX expression, results in cellular quiescence in Hodgkin-Reed-Sternberg (HRS) cells, potentially contributing to the short term failure of standard chemotherapy in cHL.