Assessment of the Relationship between Absorbed Skin Dose and Chronic Dermal Side-Effects of Radiotherapy in Patients with Breast Cancer

Considering the increasing incidence of breast cancer and patients’ delayed referral to healthcare centers، a large number of these patients are potential candidates for mastectomy and radiotherapy and will eventually suffer from early- or late-onset complications. In this study، we aimed to investigate the prevalence of chronic radiation-induced skin complications and its relation with radiation dose at skin surface in breast radiation of female patients with breast cancer. Overall، 194 female patients with non-metastatic breast cancer، who had undergone locoregional radiation therapy of breast and regional lymph nodes during 1999-2009، were enrolled in this cross-sectional study. Chronic skin complications induced by breast radiation were assessed، based on the classification of Radiation Therapy Oncology Group (RTOG). For data analysis، Chi-square and Fisher’s exact test were performed، using SPSS version 18. P-value less than 0. 05 was considered statistically significant. Among 194 patients evaluated in this study، 55 subjects (28. 4%) did not have any skin complications (grade 0). On the other hand، 50 (25. 8%)، 42 (21. 6%)، 16 (21. 6%)، and 31 (12. 6%) patients had grade 1، grade 2، grade 3، and grade 4 complications، based on RTOG system، respectively. Our results showed that radiation dose at skin surface had a significant impact on the incidence of chronic skin complications. Moreover، increase in maximum skin dose was significantly correlated with chronic skin complications (P=0. 009). As the results indicated، radiation dose at skin surface during radiotherapy is significantly correlated with chronic skin complications، and this relation should be considered in treatment planning.