Related: In First Appearance Since Revealing Her Stage 4 Breast Cancer Diagnosis, Shannen Doherty Shares Why She Feared Going Public

"I was like, 'Okay, do I have good karma? Do I have bad karma? Why would I have bad karma?' I started taking stock of my life and the things I'd done, and the things I hadn't done. How I was with people,” Doherty says.

Doherty revealed in February 2019 that her breast cancer had returned after being in remission from a previous diagnosis in 2015. This time around, the disease had progressed to metastatic  meaning it has spread to other parts of the body. In the past, metastatic breast cancer has been looked at as a “death sentence” for women, but thanks to developing research, survival rates have improved. For treatment, Doherty is undergoing hormone therapy and a targeted therapy. Seeing as there is no “cure” for metastatic breast cancer, Doherty understands she’ll be keeping the disease at bay for the rest of her life.

Dr. Elizabeth Comen breaks down the basics of metastatic breast cancer

Despite the immediate blame she put on herself after hearing about the second diagnosis, she eventually set that aside. “At the end of that, what I came out with was, I have good karma. It may not seem like it, but I've been a really good human being,” Doherty says.

A roller coaster of emotions is common for many people after a cancer diagnosis, but it’s important to remember that no one ever “deserves” to be facing this disease. It’s incredible to see that Doherty understands this.

Hormone Therapy For Breast Cancer

The most common types of breast cancers are hormone receptor-positive cancers. When a tumor is “hormone receptor positive” it means a pathologist has run special tests to determine that the cancer is positive for either the estrogen and/or progesterone receptor. If either are positive, it means that the cancer needs these receptors to grow, and physicians will determine the best treatment in order to “starve” the cells.

“What we’re trying to do is actually starve the cancer cells or any rouge cancer cells that could have escaped the breast from estrogen,” Dr. Elizabeth Comen, a medical oncologist at Memorial Sloan Kettering Cancer Center, tells SurvivorNet. “We do that by driving the estrogen levels down or by blocking the ability of estrogen to interact with the estrogen receptor on a cancer cell.”

Related: What is Tamoxifen for Breast Cancer?

However, pre and post menopausal women may experience different treatments. For pre-menopausal women, Dr. Comen says oncologists typically prescribe a medication called Tamoxifen, which blocks the ability of estrogen in a breast cancer cell from using that estrogen as a food supply. Another option is using Aromatase inhibitors, which decrease the amount of estrogen produced in cancer cells.

Dr. Elizabeth Comen explains how hormone therapy works in breast cancer

Learn more about SurvivorNet's rigorous medical review process.