For treatment of patients with inoperable cervical cancer (FIGO III) a randomized trial has been initiated. Patients were randomized to receive either conventional irradiation therapy together with vitamin A palmitate (1.5 mill. IU/day; total dose 30 mill. IU), applied orally, or irradiation alone. 42 patients have been included in this study. Patients were monitored by several immunological tests. Delayed cutaneous hypersensitivity reaction to a battery of recall antigens did not reveal any changes, neither within nor between the treatment groups. A challenge reaction to DNCB could be evoked after treatment in 50% of the patients in both treatment groups. No significant changes of immunoglobulin levels have been observed after termination of therapy in each treatment group. When lymphocyte reactivity to PHA (maximum response during therapy) was compared within the groups, it was found, that 66% of the patients who received an irradiation combined with vitamin A palmitate, showed an increase in their blastogenic response, while in irradiated patients without vitamin A palmitate a response was only in 33%. This difference being statistically significant in comparison to pretreatment values. From immunological data it can be concluded that vitamin A has an effect on functional response of T-cells. Concerning the clinical outcome, after an observation period of 12 months relapse rates were lower in the vitamin A group, but not significantly reduced. Therefore further follow up is warranted.