['Mutant p53 protein may become the target of a tumor-specific humoral and cellular immune response.', 'We used a specific qualitative p53 antibody ELISA to investigate serum samples of 33 patients with ovarian cancer taken prior to therapy. Additionally, we sought to evaluate whether p53 antibodies are also present in the sera of 17 patients with benign ovarian tumors.', 'p53 antibodies were detected in 36% of serum samples. There was a statistically significant association between p53 serum antibody response and poor overall survival (p < 0.006). No significant associations were found between p53 antibody status and histological type, histological grade, and tumor stage. In 81% of serum samples, no changes from p53 antibody negativity to positivity or vice versa during follow-up were observed. p53 antibodies were also detected in the sera of 18% of patients with benign ovarian tumors.'] Is humoral p53 antibody response a prognostic parameter in ovarian cancer?