Although the role of androgens in prostate cancer has been extensively investigated, the possible involvement of estrogens, such as estradiol and estrone, in the localized and metastatic stages of this disease remains little explored. The aim of this study was to analyze the association between plasma estradiol and estrone levels and different indicators of geriatric assessment in men diagnosed with prostate cancer, both in localized and metastatic stages. Methods: We included 67 men with a confirmed diagnosis of prostate cancer, divided into two groups: 34 with localized disease and 33 with metastatic disease. Comprehensive geriatric assessment included evaluation of sleep quality (Athens Insomnia Scale), depressive symptoms (Yesavage Geriatric Depression Scale), cognitive function (Mini-Mental State Examination, MMSE) and perception of general health status. Results: In the metastatic group, statistically significant correlations were observed between estradiol levels and Gleason index (Rho = 0.49, p = 0.03), Charlson comorbidity index (Rho = 0.51, p = 0.01) and the subscale of the Athens Scale assessing difficulty sleeping through the night (Rho = -0.62, p = 0.003).No significant correlations were found between estrone levels and any of the parameters evaluated.In the group with localized disease, a significant correlation was found between estradiol levels and the Charlson index (Rho = -0.46; p = 0.02), with no associations observed with the other geriatric variables or with estrone levels. Conclusion: Estradiol shows relevant correlations with indicators of tumor progression, comorbidity and sleep quality in prostate cancer patients, particularly in the metastatic stage. These results suggest the need to deepen the potential role of estrogens in the clinical and geriatric context of this disease.