The effect of young age on tumor recurrence in the treated breast after conservative surgery and radiotherapy.

Prognostic factors for local recurrence following conservative surgery and radiation therapy for patients with early breast cancer have not been fully established. To evaluate the importance of young age as a prognostic factor for local recurrence, we reviewed the results of treatment of 597 patients with 607 UICC-AJCC Stage I or II breast cancers, 47 of which were diagnosed when the patient was less than 35 years old. All were treated with excisional biopsy and a total dose to the site of the primary tumor of 60 Gy or more. The median follow-up in survivors was 63 months. Patient age and the presence of an extensive intraductal component (EIC) were both highly associated with the likelihood of tumor recurrence in the treated breast. Patients under 35 had an actuarial 5-year recurrence rate of 26%, compared to 10% for older patients (p = 0.002). Patients with an EIC had a breast recurrence rate of 25%, compared to 5% when EIC was absent (p less than 0.0001). Although the incidence of an EIC was higher in the younger subgroup (44% vs. 31%), this alone did not account for the difference in in breast recurrence rates, since younger patients had a higher recurrence rate than older patients even when an EIC was absent (22% vs. 3%, p = 0.0003). We conclude that the age of the patient is an important prognostic factor for local recurrence following conservative surgery and radiation therapy. This finding is in part attributed to the observation that younger women are more likely to have tumors with an EIC than older women, but even when an EIC is absent, they may be at an increased risk of local recurrence. However, caution is required in interpreting these findings with regard to selecting among treatment options until further data are available comparing the results of conservative surgery and radiation therapy to those of mastectomy in younger patients.