The rate of subsequent biopsy during follow-up care among women diagnosed with early-stage breast cancer ranged from 11.8% to 14.7% within 5 years and 14.9% to 23.4% within 10 years, according to results of a nationwide population-based cohort study.
These identified biopsy rates — which also differed based on treatment received — can be used to inform decision-making discussions with patients regarding breast cancer recurrence rates.
The rate of subsequent biopsy previously had not been available in medical literature.
“This is a genuine concern for patients. Many feel very anxious over the future need of biopsies and the potential of another diagnosis,” Henry Kuerer, MD, PhD, executive director of the department of breast programs and professor of surgery at The University of Texas MD Anderson Cancer Center, said in a press release. “Women will often choose a mastectomy rather than have the fear and stress associated with future biopsies or another cancer diagnosis.”
To determine how often patients treated for breast cancer required breast biopsies during follow-up, Kuerer and colleagues evaluated diagnosis and procedures codes for 41,510 patients aged 64 years or younger (mean age, 52.8 years) in MarketScan — a national commercial insurance database — and 80,369 women aged 66 years or older (mean age, 76.3 years) in the SEER-Medicare database.
All patients received incident invasive stage I to stage III breast cancer diagnoses between 2000 and 2011.
Median follow-up was 3.7 years (interquartile range [IQR], 2.1-5.6) for the MarketScan cohort and 5.8 years (IQR, 3.5-8.7) for the SEER-Medicare cohort.
Breast-conserving surgery served as the predominant treatment option among women in the MarketScan cohort (58.6%) and SEER-Medicare cohort (59.2%), followed by mastectomy (MarketScan, 41.4%; SEER-Medicare, 40.8%).
At 5 years, incidence of breast biopsy was 14.7% in the MarketScan cohort and 11.8% in the SEER-Medicare cohort. Rates increased to 23.4% in the MarketScan cohort and 14.9% in the SEER-Medicare cohort at 10 years.
Five-year rate of biopsy after mastectomy was 10.4% in the MarketScan cohort and 7.7% in the SEER-Medicare cohort.
Among women who underwent breast-conserving surgery, those who received brachytherapy had higher 5-year incidence rates of breast biopsy than women who underwent whole-breast irradiation in the MarketScan cohort (24% vs. 16.7%) and SEER-Medicare cohort (25% vs. 15.1%; P < .001). This association persisted in a multivariable analysis (MarketScan, HR = 1.53; 95% CI, 1.28-1.7; SEER-Medicare, HR = 1.76; 95% CI, 1.63-1.91).
Receipt of endocrine therapy appeared linked to reduced likelihood of biopsy in the MarketScan (HR = 0.88; 95% CI, 0.82-0.93) and SEER-Medicare (HR = 0.91; 95% CI, 0.85-0.97) cohorts, whereas adjuvant chemotherapy receipt increased likelihood in the SEER-Medicare cohort (HR = 1.31; 95% CI, 1.25-1.37).
Regarding patient characteristics, age 85 years or older compared with age 66 to 69 years decreased biopsy likelihood in the SEER-Medicare cohort (HR = 0.4; 85% CI, 0.36-0.44). A Charlson comorbidity index of at least 2 vs. 0 increased biopsy risk in the MarketScan cohort (HR = 1.27; 95% CI, 1.01-1.59) but decreased risk in the SEER-Medicare cohort (HR = 0.91; 95% CI, 0.85-0.97).
Among those who underwent subsequent biopsy, 29.8% (n = 1,239 of 4,158) in the MarketScan cohort and 23.2% (n = 2,258 of 9,747) in the SEER-Medicare cohort received additional breast cancer treatment within 3 months of biopsy.
Researchers noted the use of claims data may have limited these findings. Also, imaging and targeted therapies have improved since the study concluded in 2011.
However, these data are helpful for clinicians when discussing treatment options with their patients, Kuerer said.
“The important message is that the rate of biopsy for patients is relatively low and the overwhelming majority of the biopsy results will be benign and not require further treatment,” he added.
Although the size of the study cohort is a strength of these findings, limitations remain, Cheng-Har Yip, FRCS, of the department of surgery at Subjang Jaya Medical Centre in Malaysia, wrote in a related editorial.
“For patients who had breast-conserving surgery, whether the biopsy was from the ipsilateral or contralateral side was not known,” Yip wrote. “The result of the biopsy was also not ascertained from the claims data; however, because 29.8% in the commercial insurance database and 23.2% in the SEER-Medicare cohort underwent subsequent cancer treatment, some of the biopsies may not have been necessary.
“Subsequent biopsy rates are seldom discussed with women at the time of surgical decision making but may affect women’s decision and lead to an increasing number of women who opt for bilateral mastectomy,” Yip added. “The American Society of Breast Surgeons’ consensus is that contralateral prophylactic mastectomy should be discouraged in average-risk women with unilateral breast cancer, because no effect on survival has been demonstrated.” – by Alexandra Todak
Disclosures: Kuerer reports publishing patents, royalties and other intellectual property from The New England Journal of Medicine Publishing Group and McGraw-Hill Publishing; former research funding from Genomic Health; and speakers bureau roles with Physicians’ Education Resource. Please see the full study for all other authors’ relevant financial disclosures. Yip reports no relevant financial disclosures.