Freedman, G.M., Li, T., Nicolaou, N., Chen, Y., Ma, C.C.-M., & Anderson, P.R. (2009). Breast intensity-modulated radiation therapy reduces time spent with acute dermatitis for women of all breast sizes during radiation. International Journal of Radiation Oncology, Biology, Physics, 74, 689–694.

To determine differences in toxicity and time spent with radiation-induced dermatitis during a course of conventional radiation therapy (RT) or intensity modulated RT (IMRT)

At the time of treatment, a physician and nurse prospectively evaluated the skin and recorded the maximum skin toxicity each week. Chi-square and Wilcoxon analysis was used to find differences between groups from retrospective data. Multivariate analysis determined significant predictors of grade 2 or higher radiation dermatitis

• The study sample was comprised of 804 cases of breast cancer.
• Of the cases, 405 were conventional RT and 399 were IMRT.

The study included cases treated at Fox Chase Cancer Center in Philadelphia, PA.

The study used a retrospective analysis design, using cases from 2001–2006.

• Dermatitis was graded using the Common Terminology Criteria for Adverse Events version 3.0 for acute radiation dermatitis: 0 (no change) to 5 (death).
• Breast size was grouped as small, medium, or large according to bra size.
• Additional variables included tumor stage, nodal stage, chest wall separation, breast radiation dose, total dose, use and timing of chemotherapy, and receiving tamoxifen.

In all breast size groupings, a significantly lower percentage of patients in the IMRT group developed grade 2 or higher radiation dermatitis (p ≤ 0.0004). Per group, volumes that developed a maximum toxicity of grade 2 or higher were 52% for IMRT and 75% for CRT. The time spent per week of radiation with grade 2 or 3 dermatitis was lower in the IMRT group. In the IMRT group, 18% of weeks were at grade 2 or 3, and in the conventional group, 71% of weeks were at grade 2 or 3. Weeks 2–6 for those receiving IMRT had significantly less toxicity (p < 0.00001). Predictors of grade 2 or greater dermatitis found to be significant (p < 0.021) were technique (e.g., use of IMRT), large bra size, treatment week, and chemotherapy or tamoxifen administered prior to or during radiation.

IMRT is associated with less skin toxicity than conventional RT.

• Not all IMRT cases were matched to appropriate controls in the conventional group.
• Some significant differences were noted among groups in breast size and proportion of patients who also received chemotherapy.
• No information was provided on any skin care regimen used.