Elimination of "lead time" bias in assessing the effect of early breast cancer diagnosis.
The relationship between diagnosis of breast cancer in the localized stage of disease and improved prognosis for 234 female breast cancer patients aged 55 years and older was examined. Cause of death was used as an indicator of prognosis because, unlike measures of survival, it is unaffected by "lead time" bias. A three- to fourfold increase in the risk of death from breast cancer was observed among women diagnosed in the advanced stages of breast cancer relative to those diagnosed in the localized stage. The results indicate that diagnosis in the localized stage of breast cancer was associated with an improved prognosis, and that "lead time" bias cannot explain the observed association between stage at diagnosis and prognosis for female breast cancer patients aged 55 years and older.
D000328:Adult; D000367:Age Factors; D000368:Aged; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy; D005260:Female; D006801:Humans; D008875:Middle Aged; D011379:Prognosis; D012306:Risk; D013997:Time Factors