Uterus, Adenomatoid tumour

Adenomatoid tumours are benign tumours of mesothelial origin usually affecting young adults. In women, the uterus, fallopian tubes, and ovarian hilus are most commonly affected. Microscopically, they are composed of vascular-, gland-, or slit-like spaces lined by flattened, epithelioid, cuboidal cells. Adenomatoid tumours stain with mesothelial markers (e.g. WT1, calretinin, D2-40). They exhibit uniformly benign behaviour and are often incidental findings. In this case, the tumour is incidentally located in the lower right aspect of the slide, under the serosal surface. It is unrelated to the reason for hysterectomy in this case.