Abstract
The most common mesenchymal tumours of the uterine corpus originate from smooth muscle cells. Leiomyomas are commonly found in women of child bearing age; however, leiomyosarcomas occur later in life (50-55 years of age). Most uterine leiomyosarcomas occur de novo, but rare cases of leiomyosarcomas that arise from leiomyomas have been reported. We present two cases of fertile women with submucosal leiomyomas that became malignant and discuss their pathologic features and immunohistochemistry studies for P16, P53 and Ki67.