Search:

Cancer Control Research

Abstract

Women diagnosed with breast cancer are surviving longer. While increasing disease-free survivorship for some patients, adjuvant therapy may lead to chronic problems which negatively affect overall health status. Short-term risks associated with adjuvant chemotherapy have been well documented; however studies of long- term risks have been restricted to an evaluation of the increased incidence of subsequent cancers or to enumeration of comorbidities observed during or within five years after treatment. The importance of examining long-term risks is underscored by current treatment practices. Women diagnosed with breast cancer have to face difficult decisions about treatment modalities including choices of surgery, hormonal and chemotherapeutic treatments. To date, there are no estimates of the effect of adjuvant therapy on long-term survival. Given the modest benefit of adjuvant treatment, these estimates are highly relevant to treatment decision making. This research will allow patients and their physicians to balance the risks and benefits of adjuvant therapy as functions of the patient's characteristics including age, nodal status and tumor characteristics. For a group of 1,700 patients diagnosed with non-metastatic breast cancer more than five years ago, we will obtain continued follow-up on disease status, provide a prevalence and longitudinal study of physiologic late effects, and obtain a descriptive epidemiology of health related quality of life (HRQL). This group of patients will consist of five cohorts defined by their nodal and adjuvant treatment status. The first aim will be to measure comorbidity using the Charlson comorbidity index at the time of diagnosis and through the follow-up period to the last date seen. Using this index, the relationship of comorbidity to nodal status and treatment status will be estimated and compared within the five cohorts. Furthermore, using a survival analysis model developed by the investigators, cohort frailty, median survival after diagnosis, loss of expected years of remaining lifetime (of patients who remain disease-free) associated with adjuvant treatment, after adjusting for patient and tumor characteristics, will be estimated and compared among the five cohorts. Using an in-depth interview technique from a sample of 400 long-term survivors (80 per cohort), the second aim will provide a descriptive epidemiology of breast cancer and will develop a brief instrument to measure breast cancer survivors' HRQL. Using Aim 1 and 2 data, associations between HRQL, frailty, comorbidity and adjuvant treatment received will be examined.