Benign prostatic hyperplasia (BPH), light micrograph. BPH, also called prostate enlargement, is a noncancerous increase in the size of the prostate. It is an extremely common abnormality, with a frequency that rises progressively with age. BPH is characterized by proliferation of both stromal and epithelial elements, with resultant enlargement of the gland. BPH frequently appears as a nodular hyperplasia. Microscopically the hyperplastic nodules are composed of fibrotic tissue or variable proportions of proliferating glandular elements. The nodules may contain cystic spaces, the latter corresponding to dilated glandular elements. There are some inflammatory infiltrates. The scale bar corresponds to 2 millimetres.