Correcting for discretionary treatment crossover in an analysis of survival in the Breast International Group BIG 1-98 trial by using the inverse probability of censoring weighted method.

likely occurred in some individuals. The mean scores probably obscured some women with substantial symptoms or impairments and others who adapted or even experienced improved quality of life. Similarly, low mean scores for symptoms might be interpreted as indicating that all women had mild symptoms, whereas clinical experience reminds us that some women are extremely bothered by their symptoms. The proportions of women at various time points with substantially impaired quality of life and severe symptoms would also be worth knowing, especially when counseling women considering adjuvant therapy. More than half the women in these studies 2,3 were prescribed adjuvant tamoxifen, typically continued for 5 years. For some women, the adverse effects of long-term tamoxifen may be more troublesome than the short-term adverse effects of chemotherapy. For example, studies of preferences have shown that compared with women treated with adjuvant chemotherapy, women treated with adjuvant endocrine therapy judged greater survival benefits necessary to make their treatment worthwhile. 7-9 Endocrine therapy is an important potential cause of symptoms persisting 12 and 24 months after primary treatment. Before relating these results back to the clinic, we must remember that the women in these studies 2,3 were participants in randomized clinical trials; they may not be representative of the broader population of patients with cancer, which includes those with comorbidities who are at risk of poorer quality of life. 10-12 Overall, the message from the studies reported by Ganz et al 2,3 is that recovery takes time. Women of all ages with early breast cancer are at risk for a number of persisting problems, independent of their menstrual status and receipt and duration of chemotherapy. The mechanisms causing these symptoms and their persistence warrant additional study. Learning how to identify individuals at greatest risk of severe or persistent symptoms and impaired quality of life will help us devise and target interventions to prevent and manage these problems. In the meantime, these studies will help us warn and prepare women about the likelihood, severity, and duration of lingering problems after adjuvant systemic therapy.