Breast Cancer Surgery Rate Decreases With Older Age, UK Study Says

In the United Kingdom in 2015, close to 55,000 women received a breast cancer diagnosis in 2015, more than one-third of whom were older than 70 years. However, despite the proven safety of surgery as a treatment option in this group, older age, being in ill health, and frailty were still shown to influence the decision to undergo surgery following this diagnosis in the United Kingdom, where the average life expectancy of women increased from 80.5 to 82.9 years from 2003 to 2016.

A team of researchers reached this conclusion following their prospective multicenter observational cohort Bridging the Age Gap in Breast Cancer study of 3375 women with primary operable breast cancer recruited between February 2013 and June 2018 from 57 UK Breast Units. Their median age was 76 (range, 70-95) years, and 2816 (83.45%) underwent surgery, for 2854 surgical events; data for analysis were available for 99.1%.

There was a 2-year follow-up after surgery. Following a baseline assessment that took place prior to treatment, during this period, outcomes, adverse event occurrence, and quality of life (QOL) were measured at the 6-week and 6-month marks, as well as every 6 months after surgery.

“Morbidity should not be underestimated, with risk of seroma, wound complications and, in the longer term, arm morbidity such as lymphoedema and impairment of shoulder movement following axillary surgery,” the authors noted.

Mastectomy accounted for close to 40% (1138) of the surgeries, while more than 60% (1716) were breast-conserving surgeries; 80.9% of breasts in the latter group also received adjuvant radiotherapy. Of the axillary surgeries investigated, axillary lymph node dissection was the method of 20% (575) and sentinel node biopsy, 77% (2203).

The greatest predictors of choice to have a mastectomy were age, frailty, dementia, and comorbidities (multivariable odds ratio [OR] for age, 1.06; 95% CI, 1.05-1.08). In addition, age, frailty, and comorbidities were related to choosing not to have axillary surgery (OR for age, 0.91; 95% CI, 0.87-0.96).

Drilling down, following univariable analysis, the youngest group in the study (patients 70-74 years) had mastectomy in 29.9% of cases compared with 59.1% (P < .001) of the oldest group (at least 85 years). Among the patients with a Charlson Comorbidity Index score of 3 compared with above 5, there also was a lesser chance of choosing mastectomy: 34.4% vs 44.7% (P < .001).

In addition, frailty, as measured by degree of independence in activities of daily living (ADL; self-care), was associated with mastectomy in 2 measures:

• Independence in all ADLs (IADL) vs being dependent in 1 or more ADL domains: 38.8% vs 43.7% (P = .032), respectively
• Within the IADL group, independence vs not in all domains: 38.2% vs 47.3% (P < .001)

Adverse events occurred following less than 20% (551) of surgeries, and no one died with 30 days of their surgery. However, in addition to functional independence, QOL was negatively correlated with having surgery at all.

“Breast and axillary surgery are low risk in selected patients in the elderly breast cancer population, although not without complications or impact on QoL, and this should be taken into account,” the authors concluded. “Age remains an independent predictor of the type of treatment an older women with breast cancer receives.”

Study limitations include that it was not randomized, which infers an inherent bias, and missing data on some patients.

Reference

Morgan JL, George J, Holmes G, et al. Breast cancer surgery in older women: outcomes of the Bridging Age Gap in Breast Cancer study. Br J Surg. Published online June 3, 2020. doi:10.1002/bjs.11617