Journal of Geriatric Oncology
Volume 3, Issue 1 , Pages 8-16, January 2012

Does life expectancy affect treatment of women aged 80 and older with early stage breast cancers?☆

  • Mara A. Schonberg

      Affiliations

    • Division of General Medicine and Primary Care, Department of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, United States
    • Corresponding Author InformationCorresponding author at: Beth Israel Deaconess Medical Center, 1309 Beacon, Office 202, Brookline, MA 02446, United States. Tel.: +617 754 1414; fax: +617 754 1440.
    • ,
  • Edward R. Marcantonio

      Affiliations

    • Division of General Medicine and Primary Care and Gerontology, Department of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, United States
    • ,
  • Long Ngo

      Affiliations

    • Division of General Medicine and Primary Care, Department of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, United States
    • ,
  • Rebecca A. Silliman

      Affiliations

    • Geriatrics Section, Boston University Schools of Medicine and Public Health, Boston University Medical Center, Boston, MA, United States
    • ,
  • Ellen P. McCarthy

      Affiliations

    • Division of General Medicine and Primary Care, Department of Medicine, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, United States

Received 17 August 2011; received in revised form 30 September 2011; accepted 13 October 2011. published online 14 November 2011.

Article Outline

Abstract 

Background

Data are needed on how life expectancy affects treatment decisions among women ≥80years with early stage breast cancer.

Methods

We used the linked Surveillance Epidemiology and End Results-Medicare claims dataset from 1992 to 2005 to identify women aged ≥80 newly diagnosed with lymph node negative, estrogen receptor positive tumors, ≤5cm. To estimate life expectancy, we matched these women to women of similar age, region, and insurance, not diagnosed with breast cancer. We examined 5-year mortality of matched controls by illness burden (measured with the Charlson Comorbidity Index [CCI]) using Kaplan-Meier statistics. We examined treatments received by estimated life expectancy within CCI levels. We further examined factors associated with receipt of radiotherapy after breast conserving surgery (BCS).

Results

Of 9,932 women, 39.6% underwent mastectomy, 30.4% received BCS plus radiotherapy, and 30.0% received BCS alone. Estimated 5-year mortality was 72% for women with CCIs of 3+, yet 38.0% of these women underwent mastectomy and 22.9% received radiotherapy after BCS. Conversely, estimated 5-year mortality was 36% for women with CCIs of 0 and 26.6% received BCS alone. Age 80–84, urban residence, higher grade, recent diagnosis, mammography use, and low comorbidity, were factors associated with receiving radiotherapy after BCS. Among women with CCIs of 3+ treated with BCS, 36.9% underwent radiotherapy.

Conclusions

Many women aged ≥80 with limited life expectancies receive radiotherapy after BCS for treatment of early stage breast cancers while many in excellent health do not. More consideration needs to be given to patient life expectancy when considering breast cancer treatments.

Keywords: Breast cancer, Older women, Treatment, Life expectancy, Radiation

 

Back to Article Outline

1. Introduction 

The benefits of radiotherapy after breast conserving surgery (BCS) among women aged ≥80 with early stage breast cancer are not well understood even though radiotherapy after BCS is standard treatment for most younger women.1 No studies have demonstrated a mortality benefit of radiotherapy after BCS among women aged ≥80, although some studies suggest a small reduction in local recurrence.[1], [2], [3], [4] Most experts agree that older women in excellent health without comorbid disease limiting their life expectancy would be the most likely to benefit from radiotherapy after BCS.[2], [3], [4], [5]

A pooled analysis of data from several trials including women of all ages, (but few ≥70years) found that radiotherapy after BCS resulted in 7% of women experiencing a local recurrence after 5years compared to 26% of women who received BCS alone.6 This study also showed a 5.4% reduction in breast cancer mortality and a 5.3% reduction in overall mortality after 15years among women who received radiotherapy after BCS. Breast cancer recurrence was less common among women aged ≥70 (3% among women who received radiotherapy after BCS compared to 13% among those who did not).6 Data were not presented on whether the mortality benefit of radiotherapy after BCS persisted among women ≥70years. A randomized control trial (RCT) comparing mastectomy, BCS alone, and BCS plus radiotherapy including women of all ages after 20years follow-up found that radiotherapy after BCS reduced rates of ipsilateral recurrence (39.2% to 14.3%).7 There were no significant differences in distant-disease free or overall survival in the three groups; however, radiotherapy after BCS was associated with a nearly significant increase in breast cancer survival.8 These studies suggest that radiotherapy after BCS for early stage breast cancer significantly reduces local recurrence and possibly reduces breast cancer mortality after 15–20years follow-up, which is beyond the life expectancy of most women ≥80years.8

Few studies examining radiotherapy after BCS have focused on older women. One RCT included 636 women aged ≥70 with stage I, estrogen receptor positive (ER+) breast cancer treated with BCS, and randomized women to treatment with tamoxifen plus radiotherapy or tamoxifen alone. After 5years, the group that received radiotherapy experienced fewer local and regional recurrences (1% versus 4%, p<0.001) but there were no significant differences in distant recurrence or survival.1 An observational study that included women with similar characteristics found that radiotherapy after BCS reduced breast cancer recurrence from 5.1% to 1.1%.2 Another RCT that included 769 women aged ≥50 (~40% ≥70years) with node negative breast tumors, 5 centimeters (cm) or less, found that radiotherapy after BCS reduced local recurrence (7.7% to 0.6%, p<0.001) but did not show significant differences in rates of distant relapse or overall survival after 5years.3 A recent review recommended radiotherapy for all patients after BCS, except possibly women aged ≥70 with lymph node negative (LN–) tumors, 5cm or less, being treated with hormonal therapy.9 Although not all investigators agree that elderly women with favorable tumor characteristics can forgo radiotherapy after BCS, nearly all concur that those with limited life expectancies are unlikely to benefit.[2], [6], [10], [11]

In this study, we examined initial treatment of women aged ≥80 with early stage breast cancers by life expectancy. We then examined characteristics associated with the use of radiotherapy after BCS among these women.

Back to Article Outline

2. Methods 

We used data from the National Cancer Institute's linked SEER-Medicare dataset. Since 1992, SEER has included 11 population-based tumor registries in the metropolitan areas of San Francisco/Oakland, Detroit, Atlanta, and Seattle; Los Angeles county; the San Jose-Monterey area; and the states of Connecticut, Iowa, New Mexico, Utah, and Hawaii.12 These areas cover approximately 14% of the US population.13 For this study, we included 9932 women aged ≥80 with continuous fee-for-service Medicare insurance newly diagnosed with a unilateral, invasive breast cancer with tumors that were 5cm or less, no known positive lymph nodes [LN−], and ER+. Fig. 1 illustrates selection of our sample population.

2.1. Characteristics 

We obtained data on tumor characteristics at diagnosis from SEER including: tumor grade, size, stage, and histology. Patient characteristics available in SEER include: race/ethnicity, metropolitan vs. non-metropolitan residence, marital status, and year of diagnosis. Because SEER-Medicare data do not provide individual level data on income and/or education, we used census tract data and substituted ZIP code level data when not available.14 We grouped median household income and percentage of adults with less than a high school education into quintiles within registry. We determined mammography use in the previous 27months since we wanted to examine two full years of utilization data, and we hypothesized that mammograms within 3months of diagnosis might relate to diagnosis and not screening behaviors. We categorized previous mammography use sequentially as 1) non-users, 2) regular users (at least 2 mammograms 10months apart or 1 mammogram coded as screening), 3) only diagnostic mammograms within 3months of diagnosis, and 4) other.

2.2. Treatments 

We used data from both SEER and Medicare claims to classify initial treatment with surgery or radiotherapy (RT). We considered women to have received surgical and/or radiation treatment if reported in SEER or if there were Medicare claims for these treatments within 12months following diagnosis. We categorized initial treatment as mastectomy, BCS with radiotherapy, BCS alone, or no initial surgery.

2.3. Comorbidities 

We considered individual comorbidities from the Charlson Comorbidity Index and the weighted index (CCI 0, 1, 2, 3+).15 We used Klabunde's modification of the Charlson Comorbidity Index derived from both inpatient and outpatient claims to define these conditions.[15], [16], [17] We also considered several additional diagnoses from the Clinical Classifications Software (CCS).18 The CCS is a collection of 13,600 diagnoses codes and 3,700 procedure codes collapsed into 262 clinically meaningful categories. We considered CCS conditions that have a significant impact on the health and function of older adults, not already captured by the Charlson index, and were prevalent in >1% of the study population. The 10 CCS conditions we considered were Parkinson's disease, hypertension, mood disorders, thyroid disorder, blindness, pneumonia, nutritional deficiencies, gastrointestinal hemorrhage, hip fracture, and/or falls in the past two years. As we did for the Charlson, we only considered a CCS diagnosis from outpatient claims if it appeared twice separated by greater than one month to avoid “rule-out” diagnoses.

2.4. Life expectancy 

To estimate life expectancy unconfounded by the diagnosis and treatment of breast cancer, we matched women in our sample (cases) with women in the 5% random sample of Medicare beneficiaries who reside in SEER areas but who do not have breast cancer (controls). We used 5-year mortality of the matched controls as the estimated probability of 5-year mortality of the cases at the time of diagnosis. Our methods for matching have been described previously.19 Briefly, we used the greedy matching algorithm (SAS Macro GMATCH) to match women by birth year, registry location, and year of registry. The date of diagnosis of the cases was assigned as the date to begin follow-up of the matched controls. We required that the controls, like cases, had to have continuous fee-for-service Medicare the two years before follow-up. We successfully matched 98.2% of our cases with a non-breast cancer control. Controls were similar to our cases in terms of comorbidity, race/ethnicity, and income and education of residence.

2.5. Survival 

Survival time was measured from date of diagnosis (cases) or assigned date of diagnosis (controls) until death or December 31, 2006, whichever came first. We censored observations of women who were alive at the end of the follow-up period. For women diagnosed with breast cancer, we also examined breast cancer specific survival using data on cause of death from SEER through December 31, 2005.

2.6. Statistical analyses 

We used the Kaplan-Meier method to estimate 5-year mortality for the controls and to estimate 5-year overall and breast cancer mortality for the cases. We additionally estimated 5-year mortality for women with each individual Charlson and CCS condition and by the weighted Charlson Comorbidity Index (CCI) for both the cases and controls. We examined initial treatments received for women with each individual condition and by CCI (0, 1, 2, 3+). Since few women (1.8%, n=177) did not receive any initial surgery, we do not present data on these women. We then limited our sample to women treated with BCS (n=5,889) and we used multivariable logistic regression to identify sociodemographics, tumor characteristics and comorbidities (both individually and using the Charlson Comorbidity Index) associated with receiving radiotherapy after BCS. We converted adjusted odds ratios to relative risks (RR) using SAS PROC GENMOD's Poisson regression capability.20 All statistical analyses used SAS version 9.1 (SAS Institute, Cary, NC). Beth Israel Deaconess Medical Center's Institutional Review Board approved this study.

Back to Article Outline

3. Results 

Of the 9,932 women aged ≥80 diagnosed with favorable breast cancers, 58.2% were aged 80–84, 29.7% were aged 85–89, and 12.1% were aged ≥90; 43% were regular users of mammography. The majority were diagnosed with stage I disease (61.8%, Table 1). Approximately half (55.4%) had a CCI of 0 and 8.7% had a CCI ≥3 (Table 2). Based on data from controls, women with a CCI ≥3 had a substantially higher probability of 5-year mortality (72.4%) than women with a CCI of 0 (36.1%). Despite this large difference in overall mortality risk, women with a CCI ≥3 were nearly as likely to receive mastectomy (38.0% versus 40.5%) but were somewhat less likely to receive BCS+RT (22.9% versus 32.9%) than women with a CCI of 0 (Table 2). Five-year breast cancer mortality was low for all women and ranged from 5.6% among women with a CCI of 0 to 9.8% among women with a CCI ≥3.

Table 1. Sample characteristics of 9932 women aged 80 and older with estrogen receptor positive tumors, 5cm or less, with no known positive lymph nodes.
n%
Age
80–84577958.2
85–89295129.7
90+120212.1
Race/Ethnicity
Non-Hispanic White915292.2
Non-Hispanic Black3623.6
Hispanic790.8
Asian1691.7
Other1071.1
Unknown630.6
Year of diagnosis
92–95260826.3
96–00357436.0
01–05375037.8
Metropolitan status of residence
Metropolitan890289.6
Non-metropolitan103010.4
Marital status
Not married722872.8
Married237123.9
Unknown3333.4
Median income for area of residence
Lowest Quintile190019.1
2nd Quintile199720.1
3rd Quintile208221.0
4th Quintile197119.8
5th Quintile193719.5
Unknown450.5
Quintiles of education (<12years) for adults ≥25 in area of residence
Lowest Quintile183218.5
2nd Quintile192219.4
3rd Quintile201120.3
4th Quintile207720.9
5th Quintile204520.6
Unknown450.5
Mammography use in the past 2years
Non-users381038.4
Screeners423742.7
Peri-diagnosis mammogram141114.2
Other4744.8
SEER registry
Connecticut150515.2
San Francisco8298.4
Detroit120412.1
Hawaii1531.5
Iowa187018.8
New Mexico3103.1
Seattle130213.1
Utah4854.9
Atlanta5475.5
San Jose3954.0
Los Angeles133213.4
Stage
Stage I614161.8
Stage II209321.1
Unknown169817.1
Tumor Size
≤1cm360536.3
1 to ≤2cm403740.7
2 to ≤5cm229023.1
Histology
Ductal768977.4
Lobular8118.2
Mucinous6997.0
Other6846.9
Unknown490.5
Tumor Grade
Well differentiated, 1256125.8
Moderately differentiated, 2435443.8
Poorly differentiated, 3193319.5
Undifferentiated, 41251.3
Unknown9599.6
Lymph Nodes
None positive827883.4
None examined165416.6
Table 2. Five year breast and overall morbidity for 9932 women aged 80 and older with favorable breast tumor characteristics by comorbidity and for 9749 non-breast cancer controls.
MATCHED CONTROLSBREAST CANCER CASESTREATMENT RECEIVED
% (n)5-year overall mortality%% (n)5-year overall mortality %5-year breast cancer mortality %MastectomyBCS+RadiotherapyBCS alone
OVERALL100 (9749)47.3100 (9,932)41.16.739.630.430.0
Charlson Index
051.3 (5004)36.155.4 (5,498)31.65.640.532.926.6
124.5 (2391)52.223.9 (2,374)46.67.639.827.832.4
213.1 (1278)64.012.0 (1,196)55.28.836.428.834.7
3+11.0 (1076)72.48.7 (864)69.19.838.022.939.2
Individual Illnesses:
Dementia6.9 (676)80.43.0 (300)77.919.040.85.853.4
Parkinson's Disease2.0 (190)74.71.3 (129)70.08.139.520.240.3
Pneumonia6.3 (609)72.74.3 (431)66.99.939.719.740.6
Nutritional Deficiencies2.8 (274)70.21.6 (154)61.310.140.115.744.2
Congestive Heart Failure14.7 (1435)69.013.5 (1,340)65.510.837.820.841.5
Chronic Renal Failure1.9 (181)68.51.4 (140)75.313.333.827.938.2
Falls2.8 (273)68.72.1 (213)59.89.038.023.138.9
Hip Fracture3.7 (362)68.42.5 (243)61.011.943.915.640.5
Myocardial Infarction3.9 (378)63.83.6 (356)58.89.537.629.033.3
Cerebrovascular Disease10.8 (1055)64.59.0 (895)55.87.837.324.937.8
Mood Disorder7.7 (752)64.46.1 (601)52.78.834.925.040.1
COPD†12.8 (1248)63.411.4 (1,134)55.78.039.627.732.7
Peripheral Vascular Disease5.7 (554)63.45.2 (515)56.68.041.623.035.4
Cancer3.9 (382)63.24.0 (395)54.68.331.530.538.0
Diabetes14.1 (1371)58.914.0 (1,394)55.57.739.830.529.7
GI hemorrhage3.8 (371)57.13.8 (377)54.711.336.427.536.1
Peptic Ulcer Disease2.9 (279)56.81.9 (189)54.812.939.322.438.3
Rheumatologic Disease3.2 (315)51.02.5 (249)46.17.734.236.629.2
Thyroid Disorders13.2 (1289)50.414.1 (1,396)45.47.333.134.532.4
Hypertension54.3 (5297)47.756.7 (5,635)41.55.837.332.929.8
Blindness3.9 (379)44.54.7 (468)39.54.837.633.329.2

* We do not present data for women with liver disease and paraplegia since less than 1% of women received these diagnoses. However, women with these conditions were included in the Charlson Comorbidity Index.

† COPD=Chronic Obstructive Pulmonary Disease.

Examining individual comorbidities, we found that women with dementia (80.4%), Parkinson's disease (74.7%), pneumonia (72.7%), or nutritional deficiencies (70.2%) in the past 2years had the highest risk of 5-year mortality, based on data from controls (Table 2). However, nearly all women with a significant illness had greater than 50% risk of mortality in 5years. Few women with dementia received BCS+RT (5.8%) while 40.8% received mastectomies and 53.4% were treated with BCS alone. Many women with other significant illnesses limiting their life expectancies were treated with BCS+RT. For example, although women with chronic renal failure have a 69.0% risk of 5-year mortality, 27.9% received BCS+RT. Women with dementia had the highest rate of 5-year breast cancer mortality at 19.0% and were the least likely to be treated with BCS+RT. However, women with chronic renal failure had the next highest rate of 5-year breast cancer mortality (13.3%) even though many were treated with BCS+RT. Women with a history of hip fractures were the most likely to undergo mastectomy (43.9%) and were less likely to undergo BCS+RT (15.6%).

In the subset of women who received BCS (n=5,889) for their surgical treatment, 50.3% also received radiotherapy (Table 3). Although women with a CCI ≥3 were less likely to receive radiotherapy after BCS (aRR 0.7 95% CI [0.7–0.8]) than women without comorbidity, 36.9% with a CCI ≥3 still received radiotherapy after BCS. Advancing age was strongly associated with decreased likelihood of receiving radiotherapy after BCS; only 12.7% of women aged ≥90 received radiotherapy after BCS compared to 65.1% of women aged 80–84 and 38.1% of women aged 85–89. Women residing in Metropolitan areas, recently diagnosed, regular users of mammography, and those with high grade tumors were more likely to receive radiotherapy after BCS.

Table 3. Factors associated with receipt of radiotherapy after BCS among 5889 women aged 80 and older who underwent BCS*.
n% Received Radiotherapy after BCSAdjusted Relative Risk of Radiotherapy after BCS†
Overall588950.3
Characteristics:
Age
80–84337765.11.0
85–89175438.10.7 (0.6–0.7)
90+75812.70.3 (0.2–0.3)
Metropolitan status of residence
Metropolitan544452.01.0
Non-Metropolitan44529.30.8 (0.7–0.9)
Race/Ethnicity
Non-Hispanic White543950.21.0
Non-Hispanic Black21848.21.0 (0.9–1.2)
Hispanic4744.70.8 (0.6–1.1)
Asian9068.91.1 (0.9–1.3)
Other6152.50.9 (0.7–1.2)
Unknown3435.30.8 (0.6–1.1)
Marital status
Not currently married424046.81.0
Currently married144462.61.1 (1.0–1.1)
Unknown20336.00.8 (0.7–0.9)
Year of diagnosis
92–95131038.51.0
96–00214150.71.2 (1.1–1.3)
01–05243856.21.2 (1.1–1.3)
Median income for area of residence
Lowest Quintile102042.61.0
2nd Quintile115647.71.0 (0.9–1.1)
3rd Quintile120550.01.0 (0.9–1.1)
4th Quintile122852.91.0 (0.9–1.2)
5th Quintile125457.11.1 (1.0–1.3)
Quintiles of education (<12years) for those Age≥25 in area of residence
Lowest Quintile97645.21.0
2nd Quintile107049.71.1 (1.0–1.1)
3rd Quintile122048.91.1 (1.0–1.2)
4th Quintile127452.91.1 (1.0–1.2)
5th Quintile132353.71.1 (1.0–1.2)
Mammography Use
Screeners284663.01.0
Non-users195537.80.8 (0.8–0.9)
Peri-diagnosis81435.90.8 (0.7–0.8)
Other27450.00.9 (0.8–1.0)
Tumor stage
Stage I373359.51.0
Stage II84246.21.0 (0.9–1.2)
Unknown131426.80.8 (0.6–1.2)
Tumor Grade
Grade I174050.61.0
Grade II258252.01.1 (1.0–1.1)
Grade III103050.51.1 (1.0–1.2)
Grade IV5657.11.4 (1.1–1.7)
Unknown48138.51.0 (0.9–1.1)
Tumor size
≤1cm247755.61.0
1 to ≤2cm238750.61.0 (1.0–1.1)
2 to ≤5cm102536.80.9 (0.8–1.1)
Tumor histology
Ductal456850.81.0
Lobular44655.81.0 (0.9–1.1)
Mucinous41747.51.0 (0.9–1.1)
Other43641.70.8 (0.8–0.9)
Lymph node
None positive460457.01.0
None examined128526.40.7 (0.5–1.0)
SEER registry
Connecticut103152.41.0
San Francisco54851.11.0 (0.9–1.0)
Detroit74052.21.0 (1.0–1.1)
Hawaii9169.21.1 (0.9–1.3)
Iowa84733.30.8 (0.7–0.9)
New Mexico16650.01.0 (0.9–1.2)
Seattle79156.51.1 (1.0–1.2)
Utah24656.91.2 (1.0–1.3)
Atlanta29441.50.8 (0.7–0.9)
San Jose23552.31.0 (0.9–1.1)
Los Angeles90055.01.0 (0.9–1.1)
Comorbidities
Dementia1739.80.3 (0.2–0.4)
Nutrition Deficiencies8826.10.7 (0.5–1.0)
Heart Failure81233.40.8 (0.7–0.9)
Mood Disorder37838.40.8 (0.7–0.9)
Other Cancer26744.60.8 (0.7–0.9)
Peptic Ulcer Disease11136.90.8 (0.7–1.1)
Hip Fracture13327.80.8 (0.6–1.0)
Parkinson's Disease7533.30.9 (0.6–1.2)
COPD66745.90.9 (0.8–1.0)
Cerebral Vascular Disease54739.70.9 (0.8–1.0)
Pneumonia24832.70.9 (0.8–1.1)
Peripheral Vascular Disease29239.40.9 (0.8–1.1)
Chronic Renal Failure9042.20.9 (0.7–1.1)
Gastrointestinal Hemorrhage23443.21.0 (0.8–1.1)
Thyroid Disorder (not cancer)91651.51.0 (0.9–1.1)
Falls12937.21.0 (0.8–1.3)
Diabetes82350.71.0 (1.0–1.1)
Rheumatologic Disorders16055.61.1 (0.9–1.2)
Blindness28953.31.1 (1.0–1.2)
Hypertension347152.41.0 (1.0–1.1)
Myocardial Infarction21746.51.1 (1.0–1.3)
Charlson Comorbidity Index ‡
0322355.41.0
1140246.20.9 (0.8–0.9)
274345.40.9 (0.8–0.9)
3+52136.90.7 (0.7–0.8)

*Each model was adjusted for tumor characteristics (grade, tumor size, histology, stage), sociodemographics at diagnosis (age, marital status, race/ethnicity, educational attainment of census tract, ZIP code, median household income of census tract/income, metropolitan status of residence), year of diagnosis, lymph node status, mammography use, and tumor registry.

† Odds ratios were converted to Relative Risks using SAS PROC GENMOD's Poisson regression capability.

‡ In a separate model, we categorized women by their Charlson Comorbidity Index (0,1,2,3+) rather than their individual comorbidities; however, we did include conditions from the Clinical Classifications Software that were not included in the Charlson.

Women with dementia, congestive heart failure, mood disorders, and other cancers, were significantly less likely to receive radiotherapy after BCS than women without comorbidity. However, other conditions (e.g. chronic renal failure, myocardial infarction, falls) were not associated with a decreased likelihood of treatment with radiotherapy after BCS. Only 9.8% of women with dementia were treated with radiotherapy after BCS, while 45.9% of women with chronic obstructive pulmonary disease received radiotherapy after BCS (Table 3). Conversely, 44.5% of women without any of the conditions associated with >50% mortality in 5-years (all conditions in Table 2 except hypertension and blindness) were not treated with radiotherapy after BCS.

Back to Article Outline

4. Discussion 

We found that half (50.3%) of women aged ≥80 with ER+, LN− breast tumors ≤5cm received radiotherapy after breast conserving surgery. We also found that treatment with radiotherapy after BCS was not limited to the oldest women in good health; 37% of women with a 72% probability (CCI ≥3) of mortality in five years and very little chance of benefit received radiotherapy after BCS. Increasing age and the presence of dementia, which are two factors strongly associated with decreased life expectancy, were two of the strongest factors associated with not being treated with radiotherapy after BCS. However, women with many other conditions associated with high risk of 5-year mortality (e.g., chronic renal failure) commonly (42%) received radiotherapy after BCS. Conversely, 45% of women without significant comorbidities limiting their life expectancy did not receive radiotherapy after BCS. Some of these women may benefit from a reduction in 5-year local recurrence.

We found that many women aged ≥80 newly diagnosed with an early stage, ER+, LN− tumor but who also have a life threatening comorbidity are at high risk of non-breast cancer mortality in 5years. Experts encourage clinicians to consider patient life expectancy when deciding on breast cancer treatments for the oldest women.4 To our knowledge, this is the first study to examine receipt of breast cancer treatments by estimated life expectancy among older women with ER+, LN− breast cancers ≤5cm. Beyond age and dementia, clinicians may need to factor in older women's other health conditions (e.g., chronic renal failure) when deciding which treatments to recommend for early stage breast cancer. A Comprehensive Geriatric Assessment (CGA), which consists of measurement of patient's function, cognition, mood, mobility, nutritional status, medications, and social situation, can aid treatment decision making.21 Assessment-based treatment has been shown to improve the quality of life of elderly cancer patients.[21], [22]

Although a local recurrence can be a significant event in an older woman's life, few older women develop a recurrence.[1], [3], [6] Meanwhile, nearly all experience fatigue during treatment,[9], [23] and radiotherapy can cause breast pain, skin fibrosis or retraction, and edema as well as arm and shoulder pain even months following treatment.[9], [24] Serious complications of radiotherapy are rare but include radiation pneumonitis (experienced by <5% of women).25 The potential benefits of radiotherapy after BCS must be weighed against the potential risks for each woman within the context of her life expectancy. Moreover, it can be difficult for older women to arrange transportation to a radiation center for treatments.9 Transportation needs can additionally burden patients’ family members and affect family members socially or financially.

We found that a substantial proportion of women without significant comorbidities, approximately 45%, did not receive treatment with radiotherapy after BCS. Although there are no data suggesting a mortality benefit of radiotherapy after BCS among women ≥80years, some of the oldest women in excellent health may benefit due to a reduction in local recurrence.2 Furthermore, women aged 80 in excellent health have a life expectancy of more than 13years.26 Based on data from younger women suggesting a small mortality benefit of radiation after BCS after 15–20years, some of the women aged ≥80 in excellent health may not only benefit from a reduction in breast cancer recurrence but possibly even a reduction in breast cancer mortality. Studies have found that adults aged ≥80 in good health tolerate radiotherapy well. Increasingly, these women are also being offered shorter courses of radiotherapy which may be associated with fewer side effects and/or less transportation burden.24 Thoughtful consideration of patients’ comorbidities, life expectancy, and preferences, must occur when deciding on the optimal treatment of breast cancer among women aged ≥80.

Women with dementia had the greatest risk of 5-year mortality and were the least likely to receive radiotherapy after BCS, but these women were also at greater risk of death from breast cancer. These findings could suggest that women with dementia would suffer less breast cancer mortality if they were more commonly treated with radiotherapy after BCS. However, dementia is also known to be under-reported on death certificates,27 while other conditions like coronary heart disease have been shown to be overreported,28 and breast cancer may be more accurately reported.29 Therefore, among women with dementia and breast cancer, breast cancer may be more likely to be documented on the death certificate than in the case of women with breast cancer and other conditions. However, in post-hoc analyses, we found that women with dementia were more likely to have larger tumors and not have their lymph nodes assessed than other women in our study so it is also possible that women with dementia had less favorable tumors. There are no specific guidelines for treating breast cancer among women with dementia; however, studies have found that most caregivers prefer comfort care for women with severe dementia while there is great variation in preferences for women with mild to moderate dementia.30

Although this study focused on use of radiotherapy after BCS, we also found that 40% of the women aged ≥80 received a mastectomy for favorable breast cancers. Although mastectomies may have been necessary for women with the largest tumors, many others may have done well with BCS. Some women and their clinicians may have chosen mastectomy over BCS so as not to be faced with the decision of whether or not to undergo radiotherapy. Others may have received a mastectomy to avoid a second surgery in the case of a local recurrence. Such decision-making may have occurred in women that sustained hip fractures since few on average were treated with BCS+RT while more on average were treated with mastectomy. Identifying which of the oldest women may benefit from radiotherapy after BCS and which will not, may allow clinicians to feel more comfortable recommending BCS without radiotherapy rather than mastectomy to the oldest women with significant comorbidity, exposing fewer of these women to more invasive breast surgery.3

Women who were regular users of mammography screening were more likely to receive radiotherapy after BCS. This finding may reflect that older women who undergo screening are more likely to accept medical interventions in general, more likely to have access to transportation, and/or more likely to be in better health than those who are not screened. However, comorbidity scores were similar for regular users and non-users of mammography (60.7% of non-users had a Charlson score of 0 compared to 60.3% of regular users). Our findings may indicate that older women who are screened and diagnosed with breast cancer may be at greater risk of receiving treatments from which they have little chance to benefit such as radiotherapy after BCS than those who are not screened.

There are important limitations to our study. Although we do not have data on use of endocrine therapy, other studies have found that more than 80% of women ≥80years with ER+early stage tumors receive tamoxifen.31 Therefore, we limited our sample to women with known ER+tumors. However, it is possible that some women chose radiotherapy after BCS rather than treatment with endocrine therapy. In addition, adjusting for endocrine therapy use in previous studies did not alter the relationship between recurrence and radiotherapy after BCS in previous studies of older women.4 Since our data are from administrative claims we do not have data on patient preferences or treatment discussions with physicians. Furthermore, administrative data may underestimate the prevalence of many chronic conditions. However, claims data likely captures individuals with more severe disease, suggesting that we found high rates of radiotherapy after BCS among women with more severe forms of disease.[32], [33] Some of the women categorized as having no significant diseases may be misclassified and this may partly explain why many of these women did not receive radiotherapy after BCS. However, we additionally excluded women with a history of falls and other geriatric conditions associated with mortality. We also lacked individual-level data on socioeconomic status; however, studies have found a moderate association between individual and aggregate socioeconomic characteristics.14

In summary, breast cancer treatment choices for women aged ≥80 with ER+, LN− breast cancers ≤5cm are associated with life expectancy. However, many elderly women with short life expectancies receive radiotherapy after BCS while others in excellent health do not. Clinicians should consider using available prognostic tools to determine which patients are more likely to benefit from radiotherapy after BCS based on life expectancy.34 Future studies are needed to better understand how to improve decision-making around breast cancer treatment for the oldest women.

Back to Article Outline

5. Disclosures 

The authors have no conflicts of interest to report.

Back to Article Outline

6. Author Contributions 

Concept and design: Schonberg, Marcantonio, Silliman, McCarthy Data collection: Schonberg, McCarthy Analysis and interpretation of data: Schonberg, Marcantonio, Ngo, Silliman, McCarthy Manuscript writing and approval: Schonberg, Marcantonio, Ngo, Silliman, McCarthy.

Back to Article Outline

References 

  1. Hughes KS, Schnaper LA, Berry D, Cirrincione C, McCormick B, Shank B, et al. Lumpectomy plus tamoxifen with or without irradiation in women 70 years of age or older with early breast cancer. N Engl J Med. 2004;351:971–977
  2. Smith BD, Gross CP, Smith GL, Galusha DH, Bekelman JE, Haffty BG. Effectiveness of radiation therapy for older women with early breast cancer. J Natl Cancer Inst. 2006;98:681–690
  3. Fyles AW, McCready DR, Manchul LA, Trudeau ME, Merante P, Pintilie M, et al. Tamoxifen with or without breast irradiation in women 50 years of age or older with early breast cancer. N Engl J Med. 2004;351:963–970
  4. Geiger AM, Thwin SS, Lash TL, Buist DS, Prout MN, Wei F, et al. Recurrences and second primary breast cancers in older women with initial early-stage disease. Cancer. 2007;109:966–974
  5. Vinh-Hung V, Verschraegen C. Breast-conserving surgery with or without radiotherapy: pooled-analysis for risks of ipsilateral breast tumor recurrence and mortality. J Natl Cancer Inst. 2004;96:115–121
  6. Clarke M, Collins R, Darby S, Davies C, Elphinstone P, Evans E, et al. Effects of radiotherapy and of differences in the extent of surgery for early breast cancer on local recurrence and 15-year survival: an overview of the randomised trials. Lancet. 2005;366:2087–2106
  7. Fisher B, Anderson S, Bryant J, Margolese RG, Deutsch M, Fisher ER, et al. Twenty-year follow-up of a randomized trial comparing total mastectomy, lumpectomy, and lumpectomy plus irradiation for the treatment of invasive breast cancer. N Engl J Med. 2002;347:1233–1241
  8. Arias E. United States Life Tables, 2004. Natl Vital Stat Rep. 2007;56:13
  9. Buchholz TA. Radiation therapy for early-stage breast cancer after breast-conserving surgery. N Engl J Med. 2009;360:63–70
  10. Martelli G, Miceli R, Costa A, Coradini D, Zurrida S, Piromalli D, et al. Elderly breast cancer patients treated by conservative surgery alone plus adjuvant tamoxifen: fifteen-year results of a prospective study. Cancer. 2008;112:481–488
  11. Hamaker ME, Schreurs WH, Uppelschoten JM, Smorenburg CH. Breast cancer in the elderly: retrospective study on diagnosis and treatment according to national guidelines. Breast J. 2009;15:26–33
  12. Procedure Codes for Seer-Medicare Analyses. Available at: http://healthservices.cancer.gov/seermedicare/considerations/procedure_codes.html. October 29, 2009.
  13. In:  Ries LAG,  Kosary CL,  Hankey BF,  Miller BA,  Edwards BK editor. SEER Cancer Statistics Review, 1973–1994. NIH Publication Number 97–2789. Bethesda, MD: National Cancer Institute; 1997;
  14. Bach PB, Guadagnoli E, Schrag D, Schussler N, Warren JL. Patient demographic and socioeconomic characteristics in the SEER-Medicare database applications and limitations. Med Care. 2002;40:19–25
  15. Charlson ME, Pompei P, Ales KL, MacKenzie CR. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis. 1987;40:373–383
  16. Klabunde CN, Potosky AL, Legler JM, Warren JL. Development of a comorbidity index using physician claims data. J Clin Epidemiol. 2000;53:1258–1267
  17. National Cancer Institute: SEER-Medicare: Calculation of Comorbidity Weights. http://healthservices.cancer.gov/seermedicare/program/comorbidity.html. July 25, 2011.
  18. Clinical Classifications Software for Services and Procedures http://www.hcup-us.ahrq.gov/toolssoftware/ccs/AppendixASingleDX.txt. July 25, 2011.
  19. Schonberg MA, Marcantonio ER, Ngo L, Li D, Silliman RA, McCarthy EP. Causes of Death and Relative Survival of Older Women after a Breast Cancer Diagnosis. J Clin Oncol. 2011;29:1570–1577
  20. Spiegelman D, Hertzmark E. Easy SAS calculations for risk or prevalence ratios and differences. Am J Epidemiol. 2005;162:199–200
  21. Wedding U, Pientka L, Hoffken K. Quality-of-life in elderly patients with cancer: a short review. Eur J Cancer. 2007;43:2203–2210
  22. Extermann M, Hurria A. Comprehensive geriatric assessment for older patients with cancer. J Clin Oncol. 2007;25:1824–1831
  23. Lopez E, Nunez MI, Guerrero MR, del Moral R, de Dios Luna J, del Mar Rodriguez M, et al. Breast cancer acute radiotherapy morbidity evaluated by different scoring systems. Breast Cancer Res Treat. 2002;73:127–134
  24. Zachariah B, Balducci L, Venkattaramanabalaji GV, Casey L, Greenberg HM, DelRegato JA. Radiotherapy for cancer patients aged 80 and older: a study of effectiveness and side effects. Int J Radiat Oncol Biol Phys. 1997;39:1125–1129
  25. Lind PA, Marks LB, Hardenbergh PH, Clough R, Fan M, Hollis D, et al. Technical factors associated with radiation pneumonitis after local +/− regional radiation therapy for breast cancer. Int J Radiat Oncol Biol Phys. 2002;52:137–143
  26. Walter LC, Covinsky KE. Cancer screening in elderly patients: a framework for individualized decision making. JAMA. 2001;285:2750–2756
  27. Wachterman M, Kiely DK, Mitchell SL. Reporting dementia on the death certificates of nursing home residents dying with end-stage dementia. JAMA. 2008;300:2608–2610
  28. Lloyd-Jones DM, Martin DO, Larson MG, Levy D. Accuracy of death certificates for coding coronary heart disease as the cause of death. Ann Intern Med. 1998;129:1020–1026
  29. Kircher T, Nelson J, Burdo H. The autopsy as a measure of accuracy of the death certificate. N Engl J Med. 1985;313:1263–1269
  30. Smyth KA. Current practices and perspectives on breast cancer screening and treatment in older women with dementia. J Am Geriatr Soc. 2009;57(Suppl 2):S272–274
  31. Silliman RA, Guadagnoli E, Rakowski W, Landrum MB, Lash TL, Wolf R, et al. Adjuvant tamoxifen prescription in women 65 years and older with primary breast cancer. J Clin Oncol. 2002;20:2680–2688
  32. Quan H, Parsons GA, Ghali WA. Validity of information on comorbidity derived rom ICD-9-CCM administrative data. Med Care. 2002;40:675–685
  33. Wilchesky M, Tamblyn RM, Huang A. Validation of diagnostic codes within medical services claims. J Clin Epidemiol. 2004;57:131–141
  34. Schonberg MA, Davis RB, McCarthy EP, Marcantonio ER. An Index to Predict 5-Year Mortality of Community-Dwelling Adults Aged 65 and Older. J Gen Intern Med. 2009;24(10):1115–1121

☆ Dr. Schonberg was supported by a Paul B. Beeson Career Development Award in Aging supported by the National Institute on Aging K23 [K23AG028584], The John A. Hartford Foundation, The Atlantic Philanthropies, The Starr Foundation, and The American Federation for Aging Research. Dr. McCarthy was supported by the American Cancer Society [RSGT-10-080-CPHSPS]. There are no financial disclosures.

PII: S1879-4068(11)00061-0

doi:10.1016/j.jgo.2011.10.002

Journal of Geriatric Oncology
Volume 3, Issue 1 , Pages 8-16, January 2012

Article Tools

* Image Usage & Resolution