The role of chemotherapy, X-irradiation and a combination of both on the phenomenon of adherence of yeast to buccal epithelial cells (BEC) was investigated in vitro. Growth of three Candida spp. in the presence of eight of eleven antineoplastic agents led to reduction of adherence of the isolates tested (reduction between 30% and 61% of the control value), and this effect was observed whether exponential or stationary phase Candida cells were used. Exposure of C. albicans to various doses of radiation also led to a reduction in adherence of this yeast to BEC between 31% and 53% of the control value. This reduction was shown to be dose related. Similar results were obtained when BEC were exposed to radiation, and the effects of radiation treatment was accentuated when both yeast and BEC were irradiated simultaneously. Furthermore, treating C. albicans with a combination of chemotherapy and radiation led to the greatest reduction in adherence of yeast to BEC compared to when the yeast was treated with either chemotherapy or radiation alone (reduction between 63% to 74% as compared with control). The possible mechanism/s involved in reduction of adherence of yeast to BEC are discussed.