LAUSR

To compare intraoperative (IO) and postoperative (po.) boost radiotherapy (RT) in terms of local recurrence and cosmetic outcomes in patients with early-stage breast cancer during breast-conserving therapy (BCT). Patients who received BCT at our clinic in the past 60 months were analyzed based on their recorded data. Ninety-eight patients who received IO boost RT during breast-conserving surgery were classified as group A and 99 who received po. boost whole-breast RT afterward were classified as group B. Patients were graded using the LENT-SOMA (V06-7/2003) scale and compared using the chi-square test based on local recurrence and cosmetic outcomes at 1 year after the end of all RTs. Mean age of patients in groups A and B was 49 and 52 years; mean follow-up was 35 and 38 months; tumor diameter was 18 (4–30) mm and 19 (6–30) mm; and lymph node involvement was observed in 11 and 17 patients, respectively. The molecular subtypes were either luminal A or B in both groups. Histological analysis revealed 90 and 84 invasive ductal carcinomas, 8 and 5 invasive lobular tumors, respectively, and 10 mixed structure in group B. The boost area was planned so as to cover 15–20 mm of the surrounding tumor bed area in both methods. Local recurrence was not detected in group A; however, it was detected in two patients in group B at 20 and 32 months. According to the LENT-SOMA scale, 34 and 24 patients in groups A and B had grade 0, 41 each had grade 1, 21 and 29 had grade 2, and 2 and 5 had grade 3, respectively, but there was no significant difference between the two groups (p > 0.05). Based on the relatively superior results demonstrated by group A, IO boost RT can potentially improve both local control and cosmetic results.