Parity in Correlation with Stage and Estrogen Receptor Type in Breast Cancer.

Background: Parity is related to breast cancer in various ways. Its effects on the development of breast cancer are not independent and should be investigated at the same time as other reproductive factors. The association between parity and stage and type of breast cancer receptor was studied.

Methods: Parity was established for 75 patients with estrogen receptor (ER) positive breast cancer and 45 patients with ER-negative breast cancer. The stages of breast cancer were also determined.

Results: Breast cancer was found to have an association with high parity (≥ 3 parities). Significantly, most patients were diagnosed with stage II breast cancer, and this was especially frequent in patients with high parity. Stage IIB was most common, particularly among those 40-49 years old. ER-positive and ER-negative stage II breast cancer were both common among patients with high parity.

Conclusion: Breast cancer, particularly at stage II, is associated with high parity. Parity is also associated with type of breast cancer, based on estrogen receptor category. This finding supports the recommendation that breast cancer should be screened in women with a high parity. Increased births should be considered a risk factor particularly for stage II breast cancer independent of cancer type.