How to predict the risk of local relapse in the preserved breast.

In patients treated by macroscopically complete excision and breast irradiation, a small number of parameters appear to be useful in assessing the inherent risk of intramammary tumor recurrence. These factors include microscopic excision margin status, gross multifocality, very young age, EIC, and perhaps lymph vessel invasion. However, if microscopic resection margins are negative, and especially if systemic therapy is administered, local control is adequate, and none of these risk factors represents a contraindication to breast preservation. Conversely, in the absence of factors indicating an inherently greater risk of local failure, the status of resection margins is likely to be much less important. In such patients existing data suggest that satisfactory local control can be achieved by modern radiotherapy even in the face of microscopically positive margins, especially if such involvement is only focal. Final judgement on this issue awaits availability of additional long-term data from large series in which meticulous evaluation of margin status was prospectively carried out on inked excision specimens.