Appropriate evaluation of and risk factors for radiation dermatitis in breast cancer patients receiving hypofractionated whole-breast irradiation after breast-conserving surgery.

BACKGROUND

In grading radiation-induced dermatitis (RID), there are not only inter-evaluator differences but also intra-evaluator variations. We retrospectively analyzed the advantages of establishing a more precise evaluation method using photographs to minimize intra-evaluator variations and RID risk factors.

METHODS

We analyzed 301 breasts, including those of 3 patients with bilateral breast cancer who underwent hypofractionated whole-breast irradiation (WBI) after breast-conserving surgery. Four radiation oncologists (A, B, C and D) evaluated photographs taken before, during and after radiation therapy and graded RID using two methods.

RESULTS

The percentages of maximum grades between the two methods varied widely. Kappa statistics revealed that the inter- and intra-evaluator agreements were mostly fair. In multivariate analysis, age (≤60 years old), boost irradiation, concurrent hormonal therapy and chemotherapy prior to WBI are statistically significant risk factors for ≥ grade 2 RID according to two evaluators (B and D), two evaluators (A and B), one evaluator (B) and one evaluator (D), respectively.

CONCLUSIONS

The assessment of serial skin change in photographs is useful for judging RID. No risk factor was statistically significant for all evaluators because of wide intra-evaluator variations and large inter-evaluator differences. More objective criteria are needed for appropriate evaluation of RID.