Radiation therapy recommendations
The consortium guidance recommends administering radiation to patients with bleeding or painful inoperable locoregional disease, those with symptomatic metastatic disease, and patients who progress on neoadjuvant chemotherapy.
In contrast, older patients (aged 65-70 years) with lower-risk, stage I, hormone receptor–positive, HER2-negative cancers who are on adjuvant endocrine therapy can safely defer or omit radiation without affecting their overall survival, according to the guidance. Patients with ductal carcinoma in situ, especially those with estrogen receptor–positive disease on endocrine therapy, can safely omit radiation.
“There are clearly conditions where radiation might reduce the risk of recurrence but not improve overall survival, where a delay in treatment really will have minimal or no impact,” Dr. Isakoff said.
The MSKCC guidance recommends omitting radiation for some patients with favorable-risk disease and truncating or accelerating regimens using hypofractionation for others who require whole-breast radiation or post-mastectomy treatment.
The MSKCC guidance also contains recommendations for prioritization of patients according to disease state and the urgency of care. It divides cases into high, intermediate, and low priority for breast radiotherapy, as follows:
- Tier 1 (high priority): Patients with inflammatory breast cancer, residual node-positive disease after neoadjuvant chemotherapy, four or more positive nodes (N2), recurrent disease, node-positive TNBC, or extensive lymphovascular invasion.
- Tier 2 (intermediate priority): Patients with estrogen receptor–positive disease with one to three positive nodes (N1a), pathologic stage N0 after neoadjuvant chemotherapy, lymphovascular invasion not otherwise specified, or node-negative TNBC.
- Tier 3 (low priority): Patients with early-stage estrogen receptor-positive breast cancer (especially patients of advanced age), patients with ductal carcinoma in situ, or those who otherwise do not meet the criteria for tiers 1 or 2.
The MSKCC guidance also contains recommended hypofractionated or accelerated radiotherapy regimens for partial and whole-breast irradiation, post-mastectomy treatment, and breast and regional node irradiation, including recommended techniques (for example, 3-D conformal or intensity modulated approaches).
The authors of the MSKCC guidance disclosed relationships with eContour, Volastra Therapeutics, Sanofi, the Prostate Cancer Foundation, and Cancer Research UK. The authors of the COVID-19 Pandemic Breast Cancer Consortium guidance did not disclose any conflicts and said there was no funding source for the guidance.
SOURCES: Braunstein LZ et al. Adv Radiat Oncol. 2020 Apr 1. doi:10.1016/j.adro.2020.03.013; Dietz JR et al. 2020 Apr. Recommendations for prioritization, treatment and triage of breast cancer patients during the COVID-19 pandemic. Accepted for publication in Breast Cancer Research and Treatment.