Measures of Late Effects in Conservative Treatment of Breast Cancer with Standard or Hypofractionated Radiotherapy

Abstract

To confirm the equivalence in terms of late effects between two fractionation schedules of radiotherapy in conservative treatment of breast cancer. Fifty-eight patients treated at our institution from 1999 to 2002, with a median follow-up of 15 months (range, 7-46 months), were evaluated retrospectively. Twenty-nine patients (group A) were treated with standard fractionation: 5000 cGy/25fx/5 weeks, and 29 patients (group B) were treated with a hypofractionated schedule: 4500 cGy/15fx/5 weeks, three fractions per week. Late effects were evaluated using the LENT-SOMA scoring scale. The cosmetic results were assessed on a five-point scale. Skin elasticity was measured using a dedicated device (Cutometer SEM 575). There were no differences in breast volume, age at diagnosis and follow-up between groups. The LENT-SOMA toxicity observed in groups A and B, respectively, was as follows: grade 2-3 pain in five patients in each group; grade 2 breast edema in two and three patients; grade 2-3 and grade 2 fibrosis in six and eight patients; grade 2 and grade 2-3 telangiectasia in two and three patients; grade > or = 2 and 2 arm edema in two and one patients; no ulceration or atrophy were observed. Two patients in group A and one patient in group B needed treatment for breast and arm edema and arm edema, respectively. Very good, good-acceptable, and poor cosmetic results were observed in seven and two, fifteen and nineteen, and six and eight patients, respectively. Median skin elasticity loss due to treatment was -4.19% in group A and -6.29% in group B. These results are not statistically different. LENT-SOMA toxicities were minimal and no differences were observed between groups. Few patients in the hypofractionated group had very good cosmetic results, but it is debatable if radiotherapy was the only cause. Skin elasticity was not different between groups. Our results seem to suggest that it is possible to treat patients with both schedules, with similar late toxicity.