Radiobiological depth of subcutaneous induration.

The incidence of subcutaneous induration in 23 breast cancer patients with postmastectomy radiotherapy was investigated. The patients were treated with three different radiotherapy schedules 7. 9-9.8 years ago. The incidence was correlated with the biological effective dose (BED) at different depths from the skin surface and a best fit was obtained using an alpha/beta ratio of 2 Gy. The most representative depth at which to assess dose for subcutaneous induration was 2 mm which is near the subcutaneous fat/dermis interface.