Abstract 97P
Background
Radiation-associated angiosarcoma of the breast (RAAB) is a rare side effect following adjuvant radiation therapy for breast cancer and has traditionally been associated with relatively poor prognosis. There is no consensus regarding the management of RAAB and the role of re-irradiation remains undefined. We present our modern institutional outcomes in managing RAAB with the incorporation of re-irradiation.
Methods
Patients treated between 2016 and 2020 were identified from a single institution IRB approved registry. Inclusion criteria were histologically confirmed RAAB without metastatic disease at diagnosis and a history of radiotherapy to the breast/chest wall. Outcomes evaluated included local control, overall survival, acute toxicities (dermatitis, pain) and major wound complications.
Results
A total of 9 patients were identified with a median follow up of 30 months (range: 12-64 months); all had previously undergone breast conservation with adjuvant radiation with a median time to RAAB development of 7 years (range: 5-15 years). With respect to RAAB treatment, all patients underwent surgery and radiation therapy and all but one received Paclitaxel based chemotherapy. Re-irradiation was utilized in all patients with 8 receiving pre-operative re-irradiation and all patients were able to complete radiation. Five of the 8 receiving pre-operative re-irradiation had a pathologic complete response and two had < 1 cm of residual disease. At the last follow-up, 8 patients remained free of disease and one patient died with distant metastases. No local recurrences were noted. With respect to acute toxicity following re-irradiation, all patients developed at least acute Grade 2 toxicities. Five of the nine patients developed a major wound complication at some point following treatment.
Conclusions
Our institutional analysis suggests excellent local control and survival outcomes for RAAB treated with surgery, re-irradiation, and Paclitaxel-based treatment. However, wound complications represent a major challenge with this approach. Future studies should consider how best to minimize toxicity while maintaining high rates of local control and survival for patients diagnosed with RAAB.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.