To evaluate the relationship of hormone (estrogen receptor α, estrogen receptor β, progesterone receptor) and growth factor receptor (insulin-like growth factor receptor, human epidermal growth factor receptor 2) expression with disease progression in uterine carcinosarcoma.Immunohistochemistry was performed on tissue arrays using standard methodology. Differences between groups were evaluated by the Wilcoxon rank-sum test. Interactions between tumor stage and receptor expression were determined by linear trend analysis.Compared with normal endometrium, carcinosarcomas exhibited low estrogen receptor α and progesterone receptor expression (all P < .01), but overexpressed estrogen receptor β (P = .02). Estrogen receptor β expression increased in advanced stage disease (P = .02). Insulin-like growth factor receptor expression was lower in carcinosarcoma compared with normal endometrium (P = .01). Human epidermal growth factor receptor 2 expression was elevated and increased with disease progression (P < .01).In uterine carcinosarcoma, estrogen receptor β expression is elevated and increases with disease progression, whereas estrogen receptor α and progesterone receptor are suppressed. Human epidermal growth factor receptor 2 expression is increased, whereas insulin-like growth factor receptor is lower than in normal endometrium. These data support a potential role for estrogen receptor β in disease progression via crosstalk with human epidermal growth factor receptor 2.