[Prognosis-related clinicopathologic characteristics of FIGO stage Ⅰ Müllerian adenosarcoma of uterus]

Objective: To investigate the clinicopathological features of FIGO stage Ⅰ uterine Müllerian adenosarcoma and clinical prognosis. Methods: Fifteen cases of uterine Müllerian adenosarcoma at FIGO stage Ⅰ were collected at PLA General Hospital from 2005 to 2017. Twelve cases with complete follow-up data were divided into 2 groups: group A (7 patients with survival) and group B(5 patients of death or tumor progression). Clinicopathologic features were compared between the two groups. Results: The median age of the patients was 43 years and 56 years, and the tumor size was 4.3 cm and 7.3 cm for group A and B, respectively. Cases in group A were FIGO ⅠA and ⅠB stage tumors and were mainly low grade in histology (5/7) with rare tumor hemorrhagec, necrosis (1/7) and sarcomatous overgrowth. In contrast, most cases in group B were high grade sarcomas(3/5) with frequent hemorrhage, necrosis(3/5) and sarcomatous overgrowth(4/5). Most cases of group A expressed ER, PR and CD10 (6/7) and low Ki-67 index of ≤20%(5/7). While most group B cases lost expression of ER and PR (3/5), significantly reduced expression of CD10 and higher Ki-67 index of ≥30%(4/5). Conclusions: Most of uterine adenosarcomas are of low malignant potential. The main prognostic indicator is advanced tumor stage. For patients at stage Ⅰ, sarcomatous overgrowth, high-grade histology, deep myometrial invasion, decreased or absent expression of CD10, ER and PR, increased Ki-67 index(≥30%) and hemorrhagic necrosis may indicate poor prognosis. Müllerian adenosarcomas arising from endomeriosis may present unusual growth patterns.