Testing the feasibility of augmented digital skin imaging to objectively compare the efficacy of topical treatments for radiodermatitis

Abstract

Introduction Radiation-induced dermatitis (RID) is routinely graded by visual inspection. Inter-observer variability makes this approach inadequate for an objective assessment of the efficacy of different topical treatments. In this study we report on the first clinical application of a new image-analysis tool developed to measure the relevant effects quantitatively and to compare the effects of two different topical preparations used to treat RID. Materials and methods After completion of radiotherapy, RID was retrospectively assessed in 100 white female breast cancer patients who had received adjuvant breast irradiation. Of these patients, 34 were treated with R1&R2, a Lactokine-fluid derived from milk proteins, and 66 were treated with Bepanthen. In addition RID was graded independently by two experienced radiation oncologists in accordance with the Common Terminology Criteria for Adverse Events (CTCAE). For quantitative evaluation, the irradiated breast and the non-irradiated contralateral breast were photographed in a standardized manner including a color reference card. For analysis, all images were converted into the color space L*a*b* and mean values were calculated for each of the color parameters. Results The CTCAE-based grading revealed statistically significant inter-observer variability in the scoring of RID Grades 1, 2 and 3 (p<0.001). A difference between the two topical products could not be observed with visual inspection. By using augmented image analysis methods a statistically significant increase in a*-values (mean 4.15; 95%CI: 5.97–2.33, p<0.001) in patients treated with R1&R2 indicated more intense reddening. Digital subtraction was used to eliminate differences in individual baseline skin tone to generate a new, low-scatter parameter (ΔSEV). Conclusions Visual CTCAE-based evaluation of RID was not suitable for assessing the efficacy of the skin treatment products. In contrast, the novel image analysis enabled a quantitative evaluation independent of skin type and baseline skin tone in our cohort suggesting that augmented image analysis may be a suitable tool for this type of investigation. Prospective studies are needed to validate our findings.

Objective Evaluation of Risk Factors for Radiation Dermatitis in Whole-Breast Irradiation Using the Spectrophotometric L*a*b Color-Space

“…Owing to the simple and quick application, these subjective gradings are widely accepted. However, such visual assessments were shown to be prone to considerable biases due to substantial intra- and inter-evaluator differences [ 6 , 9 , 11 , 16 , 17 ]. Especially when it comes to evaluating new therapeutic strategies for RID or the combination of radiotherapy with novel immunomodulatory agents, even minimal dermatitis differences are of interest, which in turn renders objective and precise assessments indispensable [ 11 ].…”

“…Along with objectivity, a continuous scale enumerating even slight changes in the skin color also allows us to draw precise conclusions on both the development of RID and the efficacy of specific treatments [ 2 , 5 , 11 , 22 , 23 ].…”

“…However, considerable and significant intra- and inter-observer variabilities of such subjective RID gradings have been reported and it is therefore quite challenging to compare or rather interpret data obtained throughout different studies [ 9 , 10 ]. Consequently, objective and semiquantitative measurements are needed, particularly in the context of clinical RID research, in which even minimal differences are critical [ 9 , 11 ].…”

Three-dimensional surface imaging in breast cancer: a new tool for clinical studies?

“…While the use of 3DSI enables the assessment of the occurrence and development of skin changes, such as hyperpigmentation and erythema, the software lacks an automated algorithm to analyse the chromatic properties of these changes. Although such tools have been described in other works [30,31], the application of such tools in conjunction with standardized 3DSI might further improve objective assessments in future. Applying this technology in clinical studies in the field of radiation oncology could offer an additional, standardized method to objectively assess and document side effects, such as variations in breast volume or skin deterioration, and match those to subjective evaluated parameters of patient reported outcome measurements (PROMS).…”

Quantitative assessment of radiodermatitis through a non‑invasive objective procedure in patients with breast cancer

“…In this study, we used noninvasive instruments to objectively assess the patients' skin condition objectively. Conversely, Fuzissaki et al used the Radiation Therapy Oncology Group and the World Health Organization scale together, whereas Partl et al employed the application of a new image-analysis tool (20,21). These methods can help to assess a patient's skin without inter-observer variability.…”