Bilateral diffuse tumorous pseudoangiomatous stromal hyperplasia treated with bilateral mastectomy in a 40-year-old woman.

Pseudoangiomatous stromal hyperplasia (PASH) is a rare benign breast disease characterized by breast stromal proliferation mimicking low grade angiosarcoma. PASH is frequently detected as an incidental component coexisting with other breast lesions. However, it can also present as a single localized mass and is typically unilateral. Mammographic and sonographic findings are nonspecific and indistinguishable from those of benign lesions. We report an unusual case of PASH presenting with diffuse enlargement of the bilateral breasts in a 40-year-old woman treated with bilateral mastectomy.