A Question About Breast Cancer Answered at ASCO

Breast cancer is the most common cancer in women of reproductive age. Early diagnosis and advanced treatments now allow long survival.

Our patients diagnosed early, whose tumors were removed by breast cancer surgery and who completed protective treatments and remain under follow-up, resume normal life, but the question will my disease return if I become pregnant always arises.

We know that although % 50 of young newly diagnosed breast cancer patients want children, only %10 dare to become pregnant after treatment because of fear of recurrence.

This situation, a concern for us oncologists too, was clarified by a presentation at the American Cancer Congress ASCO.

Study

The study included 1207 breast cancer patients: 333 became pregnant and 874 did not plan pregnancy. Of participants, %57 had hormone-sensitive cancer. Another %40 had high-risk factors such as axillary lymph node metastasis or a large tumor. Pregnancy was planned an average of 2.4 years after diagnosis, and patients were followed for 10 years.

The study showed no difference in recurrence probability or cancer-related death risk between early-stage breast cancer patients who completed pregnancy after treatment and entered follow-up and those who did not become pregnant.

Especially in hormone-dependent breast cancer, increased estrogen during pregnancy was shown not to trigger cancer, with the disease following the same course as other breast cancer types.

In contrast, pregnancy was shown to reduce death risk by %42 in hormone-independent breast cancer. Although this striking finding may be related to protective effects of the immune system or female hormones, we believe further research is needed.

Although these results are exciting for both oncologists and patients, reassessment will be appropriate when the study is published with detailed results.