Stage 4 Breast Cancer: What You Need To Know About Survival Rates of the Disease

After being diagnosed with breast cancer in 2015—and then announcing remission of the disease in 2017—Shannen Doherty announced in early February 2020 a diagnosis of cancer again, this time with stage 4 breast cancer.

Doherty, 48, shared their diagnosis in an interview with ABC News, in early 2020 on Good Morning America. "It's going to come out in a matter of days or a week that I'm stage 4. So my cancer came back, and that's why I'm here," Doherty told Amy Robach. "I don't think I've processed it. It's a bitter pill to swallow in a lot of ways."

According to Doherty, their stage 4 cancer diagnosis came around the same time their former co-star and friend Luke Perry died, which is at least partially why Doherty kept the news a secret. But Doherty also kept their health news quiet to continue working without judgment. "One of the reasons, along with Luke—that I did '90210' and didn't really tell anybody because I thought, people can look at that other people with stage four can work too. Like, you know, our life doesn't end the minute we get that diagnosis. We still have some living to do," Doherty told ABC News.

Breast cancer, in general, is a disease with some pretty sobering statistics: According to the Centers for Disease Control and Prevention (CDC), it's the most common cancer in females, regardless of race or ethnicity, aside from some types of skin cancer; and it's the cause of death for 41,000 women and 460 men in the U.S. each year. Like most cancers, breast cancer is also divided into stages 0 to 4—the higher the number, the more cancer has spread throughout the body, and the worse the prognosis, per the National Cancer Institute (NCI).

Here's what you need to know about a stage 4 breast cancer diagnosis—and what the survival rate typically looks like.

Stage 4 Breast Cancer Explained

According to the American Cancer Society (ACS), a stage 4 breast cancer diagnosis—which is often referred to as metastatic breast cancer or terminal breast cancer—is the disease in its most serious and life-threatening form.

"Stage 4 breast cancer refers to the spread of breast cancer beyond the area of the breast and surrounding lymph nodes," Debu Tripathy, MD, professor, and chairman of the Department of Breast Medical Oncology at the University of Texas MD Anderson Cancer Center, told Health. "The more common sites of spread include the bone, lung, liver, and brain." It's important to note, however, that according to the NCI, when breast cancer spreads to bones or another area of the body, like the lungs, it does not become bone or lung cancer—it's still breast cancer.

Stage 4 breast cancer is an uncommon initial diagnosis—technically called de novo metastatic breast cancer. According to a study published in BMC Cancer in October 2020, only 5 to 10% of patients receive metastatic breast cancer as their initial diagnosis. Instead, metastatic breast cancer often emerges months or years after someone has already completed treatment for an initial breast cancer diagnosis in an earlier stage.

Treatment

Every stage 4 breast cancer diagnosis is different. This means the methods used to treat it will also differ. However, while there are differences in treatments, this stage of breast cancer is usually treated systemically (aka, via a whole-body approach), since the cancer has already spread to other areas of the body. According to the NCI, systemic treatments usually include options like hormone therapy, chemotherapy, targeted therapy, and immunotherapy.

Still, those treatments vary depending on a variety of factors, including where the cancer is located, as well as the patient's symptoms, overall health, and previous cancer treatments. Patients are closely monitored throughout treatment for the best outcome. "Patients are generally started on the treatment of best reflex or biology and followed closely using scans, with change in treatments as needed if the current treatment is not resulting in either shrinkage or stability of the breast cancer," said Dr. Tripathy.

In addition to more standard systemic treatment options, Dr. Tripathy explained that newer technologies are increasingly being used. This includes ones that sequence the DNA of cancerous tumor cells for more specified treatments, and various clinical trials designed to offer more options and possibly better outcomes to those dealing with the disease.

Life Expectancy

Overall, the main objective of terminal cancer treatment is to extend survival time while opting for treatment with the fewest possible side effects. The reason is to ensure the best and longest quality of life possible—primarily because there's no cure for stage 4 breast cancer. Some patients can respond to treatment for many years, or even decades, Dr. Tripathy said, while others with a very aggressive form of the disease may have a survival time of less than one year.

According to the American Cancer Society, the five-year survival rate for females with metastatic breast cancer—that has spread to distant regions of the body—is 29%. In comparison, for those with localized breast cancer (meaning cancer has not spread outside the breast) and regional breast cancer (when cancer has only spread to nearby structures or lymph nodes), the five-year survival rate is 99% and 86%, respectively.

However, there is some good news: Individuals are living longer with metastatic breast cancer. According to a study published in May 2017 in the journal Cancer Epidemiology, Biomarkers & Prevention, the number of females living with metastatic breast cancer in the United States is not only increasing, but patients with the disease are living longer, especially younger patients. In fact, the same study found that 11% of females under the age of 64 who were diagnosed with stage 4 breast cancer between 2000 and 2004 lived for 10 years or more.