Retrospective study of the factors involved in the development of adenomyosis and the in vitro link between adenomyosis and breast cancer.

Background and aims: Adenomyosis is a heterogeneous disease, which differs from patient to patient. The objective of our study was to evaluate the risk factors that influence the occurrence of adenomyosis, more precisely to highlight aspects that may be used in practice. In addition, the in vitro impact of levonorgestrel (a possible predisposing factor in the occurrence of adenomyosis) on MDA-MB-231 cells was evaluated, trying to obtain a link between adenomyosis and mammary cancer.

Methods: Clinical and demographic data of patients diagnosed with adenomyosis hospitalized between January and September 2023 in the Obstetrics-Gynecology Clinic were analyzed. For the in vitro assays, the MTT and LDH method was used to investigate the effect on cell viability and the potential cytotoxic effect of LG on MDA-MB-23 cells.

Results: Out of a total of 99 hysterectomies performed, the diagnosis of adenomyosis was confirmed by ultrasound in 28 cases. Among our patients, we could observe that most of cases of adenomyosis developed in women between 40 and 45 years old. Multiple pregnancies can influence the development of this uterine pathology, along with a history of uterine surgery and abortions. It was also found that treatment with sex hormones can increase the risk of adenomyosis. Our in vitro study has showed that LG stimulates the proliferation of MDA-MB-231 cells depending on the dose and time.

Conclusions: Personal history along with progestin treatment may influence myometrial lesions, leading to diffuse or focal adenomyosis. Moreover, in vitro, LG has been shown to stimulate the proliferation of breast cancer cells.