Asymmetry in oxygenation flow patterns between irradiated and contralateral breast tissues in relation to radiation dermatitis

According to the American Cancer Society, it is projected that 1.8 million new cancer cases will arise. Of these new cases, 15% are expected to be Breast Cancer related. For many subjects undergoing radiation therapy (RT), radiation dermatitis (RD) is an unavoidable adverse reaction to necessary treatment. As much as 95% of RT subjects will experience RD during or after their treatment plan which can range from mild erythema to full necrosis of the treated tissue. Further complicating matters, the standard assessment approach for RD, the Common Terminology Criteria for Adverse Events (CTCAE), is subjective and relies on the treating clinician’s visual assessment. Assessment of oxygenated blood flow changes holds potential as a means of assessing the severity of RD. In this study, spatial-temporal changes of tissue oxygenation, via a breath-hold paradigm, were monitored in breast cancer subjects across weeks of RT using a near infrared imaging approach. Subjects were imaged dynamically to acquire 2D spatial-temporal maps of tissue oxygenation. A Pearson’s correlation-based approach was applied to spatial-temporal oxygenation maps to determine the extent of symmetry or asymmetry in oxygenated blood flow patterns. Current results indicate that the oxygenated blood flow in tissue regions neighboring the irradiated site are affected by radiation dermatitis. These results are significant as they infer that RT induces altered oxygenated blood flow that could potentially be correlated to RD severity, apart from static tissue oxygenation measurements.