Adding Endocrine Therapy to Breast Cancer Treatments May Increase Symptoms

By Lorraine L. Janeczko

January 27, 2016

NEW YORK (Reuters Health) - Adding endocrine therapy (ET) to other primary breast cancer treatments may increase physical and cognitive symptoms in some women, new research suggests.

Better ET-associated symptom management needs to be a focus of survivorship care, the study authors wrote in an article online January 19 in the Journal of Clinical Oncology.

"We found that when you add endocrine therapy -- tamoxifen or an aromatase inhibitor (AI) -- after surgery, plus/minus radiation or chemotherapy, many symptoms that women have at the end of therapy do not resolve and can get worse. However, there is good recovery in overall physical functioning, while mental and emotional functioning remain good," lead author Dr. Patricia A. Ganz, of the University of California, Los Angeles Jonsson Comprehensive Cancer Center, told Reuters Health by email.

"The good news is that women did seem to recover physically. It is encouraging that, if they did not go on endocrine therapy, the severity of several symptoms actually got better, particularly hot flashes, cognitive complaints, and weight problems," Dr. Ganz said.

"In contrast, these symptoms got worse with endocrine therapy, and musculoskeletal symptom severity was worse particularly with the AI," she noted. "The contrast with the no-therapy group is important."

Dr. Ganz and colleagues compared the symptom patterns and quality of life in women with primary breast cancer who received ET with those who did not receive ET. The study participants were women 21 to 65 years old who took part in the prospective observational Mind-Body Study (MBS) between 2007 and 2010 in Los Angeles.

They were newly diagnosed with stage 0, I, II, or IIIA breast cancer, had completed primary treatments within the past three months, had not started ET, and were proficient in English.

Overall, 186 women completed in-person assessments at baseline before the initiation of ET, if prescribed, reporting data about their physical and mental health, ET-related symptoms, depression, fatigue, and sleep. They repeated these assessments at six and 12 months.

Of these, 126 women began ET, which was evenly split between AI and tamoxifen. No significant differences were found in the self-reported measures of the groups at baseline or in covariate-adjusted analyses.

Although physical health scores were initially below normative levels and improved over time, the AI group's score at 12 months was significantly lower (p=0.05). Mental health scores were normal, similar in each group, and did not change over time.

The no-ET group showed either stable or decreasing symptom severity, but the ET groups showed increased severity over time.

Compared with the no-ET group, the AI group had more severe musculoskeletal complaints (p=0.02), hot flashes (p=0.02), and cognitive problems (p=0.006) at one or both follow-up assessments.

Compared with the no-ET group, the tamoxifen group had more severe hot flashes (p=0.002), cognitive issues (p=0.016), and bladder problems (p=0.02).

Limitations of the study include its observational design, as well as the small sample size and selective patient sample: urban volunteers, who may not represent all women treated for breast cancer.

"We did this study to learn about what endocrine therapy adds to cognitive complaints after primary therapy, including chemotherapy. However, because we studied women's symptoms and quality of life in detail during the 12 months of the study, it also allowed us to examine whether any of these other symptoms were made worse," Dr. Ganz said.

"Now that we have described what happens, physicians and patients have a better idea of what to expect and what we can attribute to the addition of endocrine therapy. We need to help manage these symptoms so women will stay on treatment for five years," she advised.

The study had no external funding. Dr. Ganz reported several disclosures.


J Clin Oncol 2016.