The effect of adjuvant radiotherapy on skin biophysical properties in patients with breast cancer at risk for breast lymphedema: A prospective study

Breast cancer (BC) is the most common type of cancer among women. Radiotherapy (RT) is one of the main and primary treatment options for BC, especially in breast-conserving surgery (BCS). BC patients who underwent RT experience a wide range of symptoms, in which breast oedema and irritation of the skin take the lion's share. Breast oedema/lymphedema, which is also a prominent side effect after RT should be well determined in earlier settings due to the chronicity of lymphedema. Therefore, this study aimed to analyze the biophysical parameters of skin on the ipsilateral (IL) and contralateral (CL) sites via Tissue dielectric constant (TDC) and Transepidermal water loss (TEWL) methods in terms of oedema and skin barrier function (SBF). The following reference points before and after the RT were measured: (R1: Pectoralis muscle, R2: Upper breast, R3: Lower breast, R4: Lateral site of the thorax). A total of 24 BC patients (mean age and BMI: 52.78 ± 9.85 years and 28.42 ± 5.64 kg/m²) were evaluated. In the IL site, the SBF was not found significant in R1-R3, whereas significantly lower SBF was observed in R4 after RT (t = −3.361, p = 0.003). A significant increase in TDC was observed in R2 at the 5.0 mm depth (t = −2.500, p = 0.02). We suggest that a longer period of follow-up should be carefully carried out to track changes in terms of SBF and oedema in the irradiated breast. The increased need for early detection of changes associated with breast lymphedema can be achievable via noninvasive, safe, cheap, and easily repeatable devices.