Clinicopathologic Characteristics of Pregnancy-Associated Breast Cancer: Results of Analysis of a Nationwide Breast Cancer Registry Database.

PURPOSE

This study aimed to evaluate the clinicopathological characteristics of pregnancy-associated breast cancer (PABC) in comparison with non-pregnancy associated breast cancer (non-PABC).

METHODS

A total of 344 eligible patients with PABC were identified in the Korean Breast Cancer Society Registry database. PABC was defined as ductal carcinoma , invasive ductal carcinoma, or invasive lobular carcinoma diagnosed during pregnancy or within 1 year after the birth of a child. Patients with non-PABC were selected from the same database using a 1:2 matching method. The matching variables were operation, age, and initial stage.

RESULTS

Patients with PABC had significantly lower survival rates than patient with non-PABC (10-year survival rate: PABC, 76.4%; non-PABC, 85.1%; =0.011). PABC patients had higher histologic grade and were more frequently hormone receptor negative than non-PABC patients. Being overweight (body mass index [BMI], ≥23 kg/m), early menarche (≤13 years), late age at first childbirth (≥30 years), and a family history of breast cancer were more common in the PABC group than in the non-PABC group. Multivariate analysis showed the following factors to be significantly associated with PABC (vs. non-PABC): early menarche (odds ratio [OR], 2.165; 95% confidence interval [CI], 1.566-2.994; <0.001), late age at first childbirth (OR, 2.446; 95% CI, 1.722-3.473; <0.001), and being overweight (OR, 1.389; 95% CI, 1.007-1.917; =0.045).

CONCLUSION

Early menarche, late age at first childbirth, and BMI ≥23 kg/m were more associated with PABC than non-PABC.