Two key hormones, estrogen and progesterone, regulate a woman's reproductive system, but prolonged exposure to them can increase the risk of developing breast cancer, a Makati Medical Center (MakatiMed) doctor said.

Estrogen regulates the menstrual cycle and prepares the uterus for pregnancy, while progesterone thickens the uterine lining to receive a fertilized egg and supports milk production. Both also play a role in mood regulation, bone health, and brain function.

"High levels of estrogen and progesterone can fuel the growth of hormone-sensitive or hormone-dependent breast cancer cells," said Dr. Melodie Grace M. Remorca of MakatiMed's Breast Imaging Center. "Hormone-sensitive breast cancer cells contain hormone receptors -- estrogen receptors (ERs) and progesterone receptors (PRs). These receptors are proteins that activate when hormones bind to them. Once activated, they affect specific genes that stimulate cell growth."

While breast cancer has often been associated with genetics or lifestyle factors -- such as the case of actress Angelina Jolie, who underwent preventive surgery after testing positive for a BRCA1 gene mutation -- hormones can also play a role. The American Cancer Society estimates that about two in three breast cancers are hormone receptor-positive.

Hormone-sensitive breast cancer is treated with hormone therapy, which reduces the production of estrogen and progesterone or prevents the hormones from binding to cancer cell receptors.

"Depending on the type of hormone therapy, this treatment can slow the growth of cancer that has spread and lower the risk of it developing in other breast tissue," Dr. Remorca said. "It can also be used before surgery to shrink tumors or after surgery for at least five years to help prevent recurrence."

Common symptoms of breast cancer include a lump in the breast, nipple inversion or discharge, and changes in breast size or shape. Specialists recommend early screening for prompt diagnosis.

MakatiMed's Breast Imaging Center, considered the pioneer of breast imaging in the Philippines since 1993, offers advanced diagnostic services such as digital breast tomosynthesis (3D mammography), breast ultrasound, and several interventional procedures, including ultrasound-guided and stereotactic biopsies.

Run by an all-women team of breast radiologists, technologists, nurses, and staff, the center provides procedures that help confirm diagnoses and guide treatment options.

"Hormone therapy remains an effective approach for treating hormone-sensitive breast cancer," Dr. Remorca said. "It can reduce recurrence and improve survival rates, but early detection remains key to a favorable outcome."