Adherence to treatment guidelines and survival in older women with early-stage breast cancer in Denmark 2008–2012

Abstract

Objectives: The aims of this study were to compare patients 70 years or older with younger patients, to examine whether Danish patients with early-stage breast cancer aged 70 years or more received treatment according to guidelines, the reasons for deviating from the guidelines, and to analyze whether such deviations affected survival. Methods: From the Danish Breast Cancer Cooperative Group (DBCG) database we identified 23,247 women diagnosed with early-stage breast cancer in Denmark from 2008 to 2012. 17,391 were aged less than 70 years and 5856 were 70þ years. We reviewed medical charts of 441 patients aged 70þ years from Funen (a region of Denmark) to ascertain whether treatment was given according to the guidelines of DBCG and if not, the reason for deviating. Overall survival was analyzed by Cox proportional hazards models. Results: Up to age 80 years most women (94%) had surgery according to guidelines, decreasing to 41% in women aged 85þ years, the main reason for omitting surgery being patients' requests. Patients with breast cancer over the age of 80 years did not have an excess mortality compared with the general population in Funen. Compared with women who had surgery according to guidelines, women who did not have surgery had a significantly higher risk of dying with a hazard ratio (HR) of 8.38 (95% Confidence Intervals (CI) 4.46-15.8) if they were less than 80 years and HR ¼ 2.56 (95% CI 1.63-4.01) if they were 80 years or more (p ¼ .003 for interaction). Conclusions: Adherence to treatment according to guidelines decreases with increasing age, mainly for patients aged 80þ years. Our results suggest that surgery is important for the survival of patients aged less than 80 years.

Elderly Breast Cancer Patients Benefit from Surgery According to Guidelines

“…It should be noted, that among all our patients only 9% received primary endocrine therapy alone during the seven-year period from 2000 to 2007. This number is considerably lower than the 15% observed in a Danish study looking at all women ≥ 70 years treated for early stage breast cancer between 2008 and 2012 [5], and even lower than what has been observed across several European countries [18]. We could, based on these numbers, conclude that undertreatment with primary endocrine therapy alone at our institution is relatively uncommon.…”

“…A review from 2017 by Pepping et al however concluded that no difference in overall survival was observed comparing primary endocrine therapy with primary surgery, and they recommended that primary endocrine therapy should be considered for patients with a life expectancy of less than two years and for frail patients especially with low risk tumors [8]. Since these reviews some observational studies have demonstrated that omission of surgery is associated with an inferior overall survival: A Danish observational study by Vogsen et al including 5,856 patients ≥ 70 years diagnosed between 2008 and 2012 showed that omission of surgery among elderly women with early stage breast cancer was associated with an inferior overall survival, and in an interaction analysis this association was signi cantly more pronounced among women less than 80 years [5]. Interestingly, they further showed that the main reason for deviating from treatment guidelines was patient request [5].…”

“…Since these reviews some observational studies have demonstrated that omission of surgery is associated with an inferior overall survival: A Danish observational study by Vogsen et al including 5,856 patients ≥ 70 years diagnosed between 2008 and 2012 showed that omission of surgery among elderly women with early stage breast cancer was associated with an inferior overall survival, and in an interaction analysis this association was signi cantly more pronounced among women less than 80 years [5]. Interestingly, they further showed that the main reason for deviating from treatment guidelines was patient request [5]. A large British observational study including 23,849 patients diagnosed between 2002-2010 also showed that omission of surgery among elderly women with early stage ER positive breast cancer was associated with a signi cantly inferior breast cancer speci c survival [7].…”

“…Still, there is a lack of level 1 evidence on treatment recommendations for this group of patients, and treatment guidelines are often based on smaller subgroup analyses or extrapolations from results on younger individuals [2]. It has been demonstrated that elderly breast cancer patients more often receive less aggressive treatment than younger breast cancer patients [3,4], which can be partly explained by them having a higher degree of comorbidity, high age itself, and also because of patient preference [5]. Women above 70 years diagnosed with breast cancer have a poorer relative survival compared to younger women, and it has been suggested that this is due to nonadherence to guidelines resulting in inferior treatment [6].…”

“…Women above 70 years diagnosed with breast cancer have a poorer relative survival compared to younger women, and it has been suggested that this is due to nonadherence to guidelines resulting in inferior treatment [6]. Substantiating this, omission of surgery in elderly women with primary invasive breast cancer has been shown in several studies to result in inferior breast cancer survival [7,5,8]. Instead of primary surgical treatment of operable breast cancer, some older women are treated with primary endocrine therapy, which was rst described in the early 80's as an alternative treatment option for older women with primary invasive breast cancer [9,10].…”