Management of T1a breast cancer

Identification of early-stage breast cancers has increased over the past 2 decades primarily because of mammographic screening. The general guidelines to management of breast cancer may not apply to the smallest of these tumors, as their metastatic potential may be smaller than larger tumors. Tumors < 5 mm (T1a) carry an excellent prognosis, despite a variety of treatment approaches. However, some patients' cancer returns. There appear to be some histologic features that can predict a higher risk of axillary metastases, and therefore, a higher risk of distant metastases. Controversy exists over the extent of treatment, as to whether less than conventional treatment, such as mastectomy, axillary evaluation, and breast-conserving surgery and radiation, can be done. T1a lesions associated with extensive ductal carcinoma in situ and T1a lesions in young patients should be treated with caution if less than conventional breast treatment is to be considered. In older patients with good histologic features, axillary assessment may not be necessary. Very wide excision alone may be appropriate for some patients, but partial breast irradiation is under study and may provide a reasonable compromise. Systemic therapy for node-negative patients is not recommended. Recurrences within the breast occur later in early-stage breast cancers than with extensive-stage breast cancers, requiring annual imaging and evaluation for many years.