Comorbidities and intensity-modulated radiotherapy with simultaneous integrated boost in elderly breast cancer patients.

ABSTRACT

PURPOSE: To evaluate the impact of comorbidity assessment on compliance to intensity modulated radiotherapy with simultaneous integrated boost (SIB-IMRT) in elderly patients affected by early stage breast cancer (BC). MATERIALS AND METHODS: 40 consecutive patients were treated with SIB-IMRT (50 Gy in 25 fractions to the whole breast, and simultaneously 60 Gy to the surgical bed) for invasive BC after conserving surgery. Inclusion criteria were age ≥ 70 years, pT1-2 disease, pN0-1, no neoadjuvant chemotherapy, non-metastatic disease. Charlson comorbidity index was used for comorbidity evaluation. RESULTS: Median follow-up was 44 months. At the time of the analysis, OS and LC rates were 100%. All patients completed the SIB-IMRT without interruptions. Acute skin toxicity was recorded as follows grade 0 in 5 patients (12.5%), grade 1 in 25 cases (62.5%), and grade 2 in 10 patients (25%). Regarding late adverse events, skin toxicity was registered as follows grade 0 in 27 patients (67.5%) and grade 1 in 13 cases (32.5%). No toxicity ≥grade 2 was registered. At statistical analysis, the presence of comorbidities and the breast volume >700 cc were related to skin grade 2 acute toxicity (p = 0.01, p = 0.04). In terms of cosmetic results, 98 and 2% of patients considered the result as good/excellent and as fair after RT, respectively. No patients had a poor cosmetic outcome. CONCLUSION: The present study showed the feasibility of SIB-IMRT in early stage BC elderly patients and that the absence of comorbidity reduced the risk of acute radiation toxicity.