A history of breast cancer is a risk factor for the development of endometrial pathologies, such as typical and atypical glandular hyperplasia, endometrial polyps, uterine fibroids, endometrial adenocarcinoma and uterine sarcoma, probably due to some common risk factors (eg. obesity, nulliparity). Even if ethiopathogenesis for breast cancer and endometrial pathologies is not well established, both genetic factors and hyperestrogenic state may be play a pivotal role for their development. Indeed, relative hyperestrogenism is also the main target for the treatment of breast cancer. Currently used therapies for this purpose are selective estrogen receptor (ER) modulators (SERMs), such as Tamoxifen (TAM), and third generation non-steroidal aromatase inhibitors (AIs), such as letrozole and anastrozole.

TAM has both agonist and antagonist properties, depending upon the individual target organ and circulating levels of serum estrogens: on the one hand, it blocks estrogen stimulation in breast tissue; on the other hand, TAM shows an ER agonist activity in the endometrium that is able to stimulate proliferation and, in some cases, it causes an increased risk of uterine pathologies. Women with hormone-dependent breast cancer have to use TAM for five to ten years. Many reports suggest that the risk of uterine pathologies increases with the time of administration.

Considering these elements, the primary aim of this study will be to investigate the incidence of endometrial pathologies, especially of endometrial cancer, in different groups of breast cancer women undergoing diagnostic hysteroscopy.

Inclusion Criteria:

• History of breast cancer treated with surgery (regardless of the adjuvant radio/chemotherapy)

Exclusion Criteria:

• Incomplete data collection
• Recurrence of breast cancer
• Any other concomitant disease
• Any pharmacological treatment (wash-out: 3 months) other than Tamoxifen or Aromatase inhibitors
• Women who switched from a therapy to another one during the study period.

Breast cancer women with or without hormonal therapy, undergoing diagnostic hysteroscopy and targeted endometrial biopsy.