Age as a prognostic factor for patients treated with definitive irradiation for early stage breast cancer.

From 1977 to 1986, 88 breast cancers in 86 women age less than or equal to 35 years were treated with definitive irradiation following breast-conserving surgery. The records of these cases were reviewed and compared to 808 breast cancers in 798 women age greater than or equal to 36 years treated similarly during the same time period. All women had AJC clinical Stages I or II invasive carcinoma of the breast and had undergone an axillary surgical staging procedure to determine pathologic lymph node staging prior to receiving definitive radiotherapy. There was no statistical difference between the younger and older women in terms of 5-year actuarial overall survival (94% vs. 90%), NED survival (78% vs. 81%) or relapse-free survival (70% vs. 77%). Although the younger women tended to have an earlier pattern of failure, the difference between the actuarial percentage of failures at 5 years for the two age groups was not significantly different for local only first failure (9% vs. 5%), regional only first failure (6% vs. 3%), and local and regional only first failure (0% vs. 1%). Subset analyses also did not show a difference between the younger and older patients. Although longer follow-up will be needed to confirm these observations, our 5-year results show that younger patients less than or equal to age 35 do not have an adverse outcome in terms of survival, local control, or regional control when compared with older patients greater than or equal to age 36. Potential candidates for definitive irradiation following breast-conserving surgery should not be excluded for treatment solely on the basis of younger age less than or equal to 35 years.