Abstract

Müllerian adenosarcomas are tumours of low malignant potential with proliferation of benign glands and low grade endometrial stromal sarcoma (LGESS). Unusually, the latter may include foci of uterine tumours resembling ovarian sex-cord tumours (UTROSCT). Two cases of uterine adenosarcomas massively overgrown by UTROSCT are reported, for the first time. The patients, aged 71 and 64, one receiving tamoxifen, presented with intracavitary polypoid adenosarcomas; each was overgrown by an immunopathologically characteristic UTROSCT that constituted more than 75% of its volume. Periglandular CD10+LGESS represented less than 25%. Both are alive and well after 5 and 3 years, respectively. Compared to the poor prognosis of adenosarcomas overgrown by high grade sarcomata, the cases reported here had a benign behaviour. Quantitative assessment of volume percentage of the potentially aggressive LGESS, CD10+ areas should be considered as a relevant prognostic histological parameter in these tumours.