Figure 14a. Adenocarcinoma arising from adenomyosis in a 71-year-old woman. (a) Sagittal T2-weighted image shows a mass (M) in the submucosal area of the posterior region. The mass is hyperintense relative to the myometrium. (b) Sagittal T2-weighted image obtained 1 cm lateral to a shows that the margins of the mass (M) are indistinct at its periphery. Arrows = endometrium. Histologic examination of the surgical specimen revealed endometrioid adenocarcinoma arising from adenomyosis.