A Clinicopathologic Study of Breast Cancer Patients during Pregnancy

Background & Aims : The purpose of this study was to investigate the influence of pregnancy on breast cancer prognosis by analyzing clinical and pathological features of young patients with breast cancer in relation to last birth. Method : A total of 622 young breast cancer patients under 35 years of age undergoing surgical treatment between 1960 and 1990 at Cancer Institute Hospital were included in this study. The patients were classified into four groups ; group A patients who were diagnosed during pregnancy or within one year after delivery, group B patients who were diagnosed from one to three years after delivery, group C patients who were diagnosed three years or more after delivery, and group D patients who were nulliparous. All four groups were examined from the viewpoint of clinical and pathological findings with regard to age, disease duration, first childbirth, clinical stage, histopathological type, lymph node metastasis, and survival. Furthermore, nuclear grade and immunohistochemical staining of both estrogen receptor (ER) and factor-VIII were examined in early-stage breast cancer patients. Result : The incidence of early-stage (0, I and II) breast cancer was significantly (p<0.05) lower in group A (69%) than in groups C (88%) and D (85%). The incidence of nodal involvement decreased from group A (61%), B (59%), C (51%) to D (43%) in that order. The incidence of nodal involvement in group D was significantly (p<0.05) lower than that in groups A and B. The positive rate of estrogen receptor increased from group A (50%), B (56%) to C (72%) in that order. Disease-free survival was significantly (p<0.05) more favorable in group D than in groups A and C. The similar result was obtained in patients with clinically early-stage breast cancer. Conclusion : Patients who developed breast cancer during pregnancy or within less than one year postpartum have a poor prognosis among patients under 35 years old. Patients having no childbirth history generally have a high risk factor of developing breast cancer, however, breast cancer patients without childbirth history under 35 years old result in a favourable prognosis.