Outcomes After Palliative Radiation Therapy in Patients With Symptomatic Locoregionally Advanced Breast Cancer

Abstract

Purpose: Symptomatic locoregionally advanced breast cancer (SLABC) can cause troublesome pain or wound complications that negatively impact quality of life. Although palliative radiation therapy (RT) can minimize tumor-related symptoms, how best to tailor RT to achieve the most meaningful and durable response is not well defined.

Methods and materials: This is a single institution, multi-site retrospective review of patients with SLABC treated between 2016 and 2023 with palliative RT to symptomatic disease in the breast, chest wall, and/or regional lymph node basins. Overall survival (OS), locoregional control (LC), clinical and radiographic treatment response, overall pain scores, and treatment-related toxicities were analyzed.

Results: A total of 164 patients with a median age of 57 years were analyzed with a median follow-up time of 4.97 months. In total, 86% had distant metastases. The most common presenting symptom was pain (87%), followed by ulcerating or fungating lesion (76%) and discharge (45%). The median cumulative biologically effective dose to the gross tumor volume (BED_GTV) was 69 Gy. The 1-year OS and LC rates were 37% and 63%, respectively. Eighty-one percent experienced improvement in symptoms within 3 months after RT, the odds of which increased per Gy BED_GTV (odds ratio, 1.029; P = .003). Acute toxicities were associated with number of fractions and BED_GTV (both P < .001), but not with concurrent systemic therapy or reirradiation (both P > .05). Trends in pain scores showed a significant change in pain trajectory that was sustained during the first year after RT. OS and LC were not different among patients who received 1 versus 2 to 10 versus >10 fractions, and between ≤70 and >70 Gy BED_GTV.

Conclusions: In this large series of patients with SLABC, palliative RT was effective at relieving locoregional symptoms with acceptable toxicity, with the likelihood of symptom improvement associated with radiation dose. Survival of these patients remains poor, highlighting the importance of palliative care strategies that minimize overall symptom burden while maximizing quality of life.

Fig. 1.

Overall survival of the entire population (A), stratified into 1 versus 2–10 versus >10 fractions (B), and stratified into ≤70 versus >70 Gy cumulative BED_GTV (C). Abbreviation: BED_GTV = biologically effective dose to the gross tumor volume.

Fig. 2.

Local control of the entire population (A), stratified into 1 versus 2–10 versus >10 fractions (B), and stratified into ≤70 versus >70 Gy cumulative BED_GTV (C). Abbreviation: BED_GTV = biologically effective dose to the gross tumor volume.

Fig. 3.

Overall pain scores of the entire population modeled as a function of time before and after palliative RT. Centered pain scores translated around zero are depicted in the y-axis, and time in days indexed at the start of palliative RT as zero in the x-axis. Dashed lines represent the 95% confidence interval of pain scores. Pain scores appeared to plateau after RT through approximately day 500. Abbreviation: RT = radiation therapy.