Focal endometrial stromal hyperplasia.

AIMS: To describe a patient in whom multiple endometrial biopsies revealed stromal proliferative lesions causing diagnostic difficulty.

METHODS AND RESULTS: A 39-year-old woman with a history of menorrhagia and dysmenorrhoea underwent two endometrial biopsies and hysterectomy. In each case histopathology revealed apparently multifocal benign stromal proliferative lesions with no evidence of invasive growth pattern. The lesions were characterized by increased cellularity, nuclear enlargement and spindle cell morphology but no mitotic activity or nuclear pleomorphism were seen. The possibility of low grade stromal neoplasm was considered in the biopsy specimens. The hysterectomy revealed no evidence of malignancy but foci of ovarian endometriosis and cervical stromal endometriosis were present.

CONCLUSION: We suggest that the lesions represent focal endometrial stromal hyperplasia, a potential mimic of stromal nodule or stromal sarcoma in biopsy samples.