UC Davis researchers examine risks, benefits of chemotherapy for early-stage breast cancer

Joy Melnikow, professor in the Department of Family and Community Medicine and Director of the Center for Healthcare Policy and Research at UC Davis, is working to define the potential long-term harms of chemotherapy for these patients, so they can be weighed against the potential benefits.

Joy Melnikow Joy Melnikow

Her study, funded by the National Cancer Institute (NCI), aims to better inform physicians and their patients about optimal treatment strategies. She also hopes to identify gaps in the evidence to date that require additional research.

“It‘s important to know when you can say the evidence is strong and when it is not,” she said.

Melnikow said treatment regimens vary for early-stage invasive breast cancer. In many cases, women opt for a lumpectomy (surgical removal of the tumor) with radiation, or a mastectomy (removal of one or both breasts) with the addition of hormonal therapy and/or chemotherapy and sometimes trastuzumab (Herceptin), a monoclonal antibody treatment.

“The survival from treatment with or without adjunctive chemotherapy is extremely good for many women with early-stage disease, so the incremental benefit of chemotherapy may be small,” she said. “The question is how to balance the benefits with the potential long-term harms of chemotherapy.”

Melnikow and her colleagues are conducting a series of systematic reviews of the published literature to extract and synthesize what is known about a range of potential long-term harms of chemotherapy for early-stage breast cancer. The harms may include congestive heart failure, ovarian failure (for premenopausal women), peripheral neuropathy, cognitive impairment, and secondary cancers from the effects of chemotherapy on the DNA of non-breast cancer cells. 

In addition to identifying and reviewing all available published evidence on the topic, Melnikow also is working with her colleagues to mine previously unpublished data from the NCIB-30 trial of chemotherapy regimens for early-stage breast cancer.

“We hope our work will provide new information to help women and their doctors make decisions about breast cancer chemotherapy,” she said. “We also expect to define critical gaps in the evidence that can inform future research in this area.”

UC Davis Comprehensive Cancer Center
UC Davis Comprehensive Cancer Center is the only National Cancer Institute-designated center serving the Central Valley and inland Northern California, a region of more than 6 million people. Its specialists provide compassionate, comprehensive care for more than 10,000 adults and children every year, and access to more than 150 clinical trials at any given time. Its innovative research program engages more than 280 scientists at UC Davis, Lawrence Livermore National Laboratory and Jackson Laboratory (JAX West), whose scientific partnerships advance discovery of new tools to diagnose and treat cancer. Through the Cancer Care Network, UC Davis collaborates with a number of hospitals and clinical centers throughout the Central Valley and Northern California regions to offer the latest cancer care. Its community-based outreach and education programs address disparities in cancer outcomes across diverse populations. For more information, visit cancer.ucdavis.edu.