Kathryn A. Gold, M.D., associate clinical professor at University of California San Diego School of Medicine, presented data showing an increase in people diagnosed with advanced stage breast cancer in 2020 and 2021, compared to 2019.
June 8, 2021 — Reporting at the 2021 annual meeting of the American Society of Clinical Oncology, Kathryn A. Gold, M.D., associate clinical professor at University of California San Diego School of Medicine, presented data showing a decrease in people diagnosed with early stage breast cancer and an increase in those diagnosed with advanced stage breast cancer in 2020 and 2021 compared to 2019.
In 2019, 2 percent of Moores Cancer Center at UC San Diego Health patients received a new diagnosis of stage IV breast cancer, also known as metastatic disease. That increased to 6 percent in 2020 and 8 percent so far in 2021.
“Based on our clinical experiences, we suspected that we would see an increase in late-stage cancer diagnoses and our data is showing that to be true for breast cancer,” said Gold, medical oncologist at UC San Diego Health. “Patients with breast cancer were more likely to be diagnosed with more advanced disease after the start of the COVID-19 pandemic, possibly due to delayed and cancelled preventative screenings.”
The number of patients with the earliest stage of breast cancer, called stage I, decreased from 64 percent in 2019 to 51 percent in 2020 and 42 percent so far in 2021. While stage I breast cancer is often treatable, stage IV breast cancer is more life-threatening.
When the SARS-CoV-2 virus that causes COVID-19 emerged, hospitals were forced to re-evaluate which clinics would continue to see patients in person, which would need to move to telehealth and which would need to pause treatment altogether. Although hospitals have resumed all operations individuals have missed annual screenings or remain hesitant to resume active health care.
“Regular screenings and visits to your physician are an essential part of maintaining good health. We encourage everyone to get back to your doctor’s office for preventive care because early detection saves lives. Don’t delay,” said Gold.
The National Cancer Institute estimates 281,550 women will be diagnosed with breast cancer in 2021. Although 1 in 8 women will be diagnosed with breast cancer in their lifetime, 90 percent of patients with breast cancer survive five years or longer due to early detection and treatment. Despite a high survival rate, 43,600 women will die from the disease this year.
Additional information about breast cancer:
- Mammography is the most effective tool for screening breast cancer
- The Women Informed to Screen Depending on Measures of Risk (WISDOM) clinical trial at UC San Diego Health aims to uncover whether annual mammograms are the best way to screen for breast cancer or whether a personalized approach is best; information is available at http://www.thewisdomstudy.org/
- Breast cancer is the second leading cause of cancer death in women behind lung cancer
- There are more than 3.5 million breast cancer survivors in the United States
- Men can also develop breast cancer, although it is much less common
At Moores Cancer Center, San Diego’s only National Cancer Institute-designated comprehensive cancer center, patients with breast cancer have access to the expertise of a tumor board and specialists in medical, radiation and surgical oncology, as well as palliative care and survivorship to design a treatment as unique as they are.
For more information: https://health.ucsd.edu/
March 12, 2026 
