As the aging population in the United States continues to grow, the incidence of diseases of the elderly, such as breast cancer, are increasing. Many more elderly women are expected to be diagnosed with new breast cancers, most of them in an early stage. Appropriate treatment of these women is important, as they have poorer outcomes when undertreated. In this review, we will discuss the biology and treatment of early breast cancer in elderly women. We will focus on the role of comorbidity and its effect on life expectancy, treatment decisions, current recommendations for primary treatment with surgery, radiation and neoadjuvant strategies, and adjuvant treatment including local radiation therapy and systemic treatment with endocrine therapy, chemotherapy, and newer agents. Finally we will discuss the importance of clinical trials in the elderly.
Despite the fact that most breast cancers in the United States are diagnosed in women over 60, we have little objective data on which to base our treatment recommendations. The authors have provided a comprehensive review of the controversies and therapeutic challenges in treating breast cancer in elderly women. At the heart of the dilemma is the fact that the death rate from breast cancer in this population is disproportionately higher than in younger women. Meanwhile, known prognostic factors such as nodal, hormone receptor, and HER2 status would predict for a more indolent disease process, leading us to ask, "Are we undertreating elderly women with breast cancer?"
False Assumptions
In reviewing available data, it is clear that treatment decisions have often been based on false assumptions. Underutilization of breast-conserving therapy is one such example. When asked, one-third of women over 67 report that body image is important to them. It has been shown that women for whom body image is important but who were treated by mastectomy had poorer mental health outcomes after 3 months than women who were treated according to their preference or who had no preference for local therapy.[1] In the absence of data, perhaps we have come to similar conclusions regarding systemic therapy.
It has been demonstrated that physicians are often reluctant to offer adjuvant therapy-even hormonal therapy. This is especially troubling as most cancers in the elderly are hormone receptor-positive; the impact on disease-free survival with adjuvant tamoxifen is similar to what has been observed in younger women.[2] Perhaps an increased awareness of the benefits of adjuvant therapy and the option of using aromatase inhibitors that have a more favorable toxicity profile will result in more consistent use of adjuvant hormonal therapy. Adjuvant chemotherapy is a more complex issue. Older women do benefit from chemotherapy, though somewhat less than younger women. The authors have thoroughly reviewed the differences in toxicity of the various chemotherapy combinations, which also must be considered.
Three Key Factors
Drs. Witherby and Muss identify three important factors in determining the risk-benefit ratio of adjuvant therapy in this population-breast cancer-specific prognosis, non-breast cancer-specific prognosis, and treatment-related toxicity. Breast cancer-specific prognosis may be determined from the literature and the Adjuvant! Online website (www.adjuvantonline.com). The ability to assess an elderly patient's non-breast cancer-specific prognosis and anticipate treatment-related toxicity requires the expertise of a geriatrician. The components of the comprehensive geriatric assessment are summarized in the Witherby and Muss article. However, it is probably not realistic that busy oncologists will commit the time required to complete even a modified geriatric assessment (at least 20 minutes for a mini-Comprehensive Geriatric Assessment [CGA]; a full CGA may take 1 to 2 hours for a trained geratrician to complete.[3]). How can the practicing oncologist quickly obtain this information during the clinical assessment?
Other Evaluation Methods
Most oncologists are comfortable with the Karnofsky performance status (KPS) scale, which is used to assign a number (100 being normal) to a patient's ability to function. The assessment is made by the physician after speaking with the patient. The ability of the patient to "talk the talk" is reproducible from physician to physician. Yet the KPS has never been validated in the elderly patient and will not identify geriatric syndromes such as dementia or incontinence.
A more typical geriatric measure-independent activities of daily living (IADLs)-has been shown to be superior to the KPS in determining the patient's functional reserve. For example, a KPS of 2 indicates that the patient is out of bed more than 50% of the day. Yet that score does not tell us if the patient was dressed or fed by a caregiver. The assessment of IADLs provides a more accurate measure of the patient's function and establishes that the patient can "walk the talk."
Long-term survival and the ability to administer treatment are strongly linked to the number of comorbid medical conditions from which the patient suffers. A number of comorbidity scales have been developed.[4] For the practicing oncologist, it is important to acknowledge that survival and the ability to tolerate therapy are inversely related to the number and severity of comorbid conditions. In the breast cancer population, cerebrovascular disease and dementia have been shown to impact prognosis more than diabetes or hypertension.[5]
Gait speed in the elderly correlates with functional status and prognosis. In geriatrics, objective measures of function utilize the distance an individual can walk in 6 minutes or the number of times the patient can get up from and sit down in a chair and whether they need to use the arms to right themselves.[6] A recent study utilized a 6-meter course and found that gait speed < 1 m/s identified individuals at high risk of health-related outcomes.[7] The oncologist can derive significant information about physiologic age by simply asking the patient to get out of a chair and walk.
Conclusions
The authors have provided us with the pertinent issues in managing elderly patients and emphasize the importance of enrolling patients in clinical trials to address the many unanswered questions. Clinical assessment of an older woman should include information about the patient's IADLs and should assess her ability to get out of a chair unassisted and to walk at a reasonable pace. Women whose physiologic status suggests a favorable outcome should be treated similarly to younger patients, while those who are more frail should be treated less aggressively. The management of breast cancer in this population requires us to be astute observers.
-Joanne E. Mortimer, MD
The author has no significant financial interest or other relationship with the manufacturers of any products or providers of any service mentioned in this article.
1. Figueiredo MI, Cullen J, Hwang YT, et al: Breast cancer treatment in older women: Does getting what you want improve your long-term body image and mental health? J Clin Oncol 22:4004-4008, 2004.
2. Exterman M, Meyer J, McGinnis M, et al: A comprehensive geriatric intervention detects multiple problems in older breast cancer patients. Crit Rev Oncol Hematol 49:69-75, 2004.
3. Early Breast Cancer Trialists' Collaborative Group: Polychemotherapy for early breast cancer: An overview of the randomized trials. Lancet 352:930-942, 1998.
4. Gasney MA: Clinical assessment of elderly people with cancer. Lancet Oncology 6:790-797, 2005.
5. Louwman WJ, Janssen-Heijnen ML, Houterman S, et al: Less extensive treatment and inferior prognosis for breast cancer patient with comorbidity: A population-based study. Eur J Cancer 41:779-785, 2005.
6. Klein BE, Klein R, Knudtson MD, et al: Frailty, morbidity and survival. Arch Gerontol Geriatr 41:141-149, 2005.
7. Cesari M, Kritchevsky SB, Penninx BW, et al: Prognostic value of usual gait speed in well-functioning older people-Results from the Health, Aging and Body Composition Study. J Am Geriatr Soc 53:1675-1680, 2005.