Hepatobiliary cystadenomas with mesenchymal stroma are rare neoplasms, which occur only in females; they have a strong tendency to recur and a potential for malignant transformation. Microscopic features are characteristic but clinical findings are highly variable and laboratory data non specific. We report 5 cases with immunohistochemical study, showing the characteristics of mesenchymal stromal cells: myofibroblastic phenotype and expression of progesterone receptors in all cases and estrogen receptors in 3 out of 5 cases. These results point out the possible hormonal dependance of this tumor.