Cell death after treatment with chemotherapy is exerted by activation of apoptosis, and the p53 protein has been shown to actively participate in this process. This recent focus on TP53 status as a possible determinant of cancer therapy response has raised the question of whether or not mutations in the TP53 gene have an influence on paclitaxel therapy. The TP53 status has been analysed at the DNA level in tumours from 45 ovarian cancer patients randomized to treatment with paclitaxel and cisplatin or cyclophosphamide and cisplatin. Therapy response was obtained for 38 patients with clinically evaluable disease after initial surgery. The positive response rate to the paclitaxel/cisplatin therapy was 85% vs 61% for the patients who received the cyclophosphamide/cisplatin regimen. A significant difference in relapse-free survival in favour of paclitaxel/cisplatin chemotherapy was found (P = 0.001). A total of 33 tumour samples (73%) had detectable sequence alterations in the TP53 gene. When relapse-free survival was estimated for all patients with TP53 alterations in their tumours, a significant better outcome for the paclitaxel/cisplatin group was found compared with the patient group receiving cyclophosphamide and cisplatin therapy (P = 0.002). We did not observe an association between TP53 tumour status and prognosis for patients who received paclitaxel/cisplatin combination treatment, indicating that the effect of this therapy is not influenced by this parameter.