By Kim Polacek, APR, CPRC - June 07, 2022
Luminal A breast cancer accounts for almost 60% of breast cancer diagnoses. It is a slow growing, low-grade cancer that doesn’t often spread to other cells, which provides a good prognosis for this group of patients. Standard therapy for early stage tumors typically consists of breast conserving surgery (lumpectomy) followed by radiation therapy to reduce the risk of local recurrence. However, new research shows that reducing the treatment burden of radiation therapy can be an option in certain patients. This can minimize treatment costs and symptoms from radiation therapy that can include skin irritation, fatigue, breast pain and distortion.
New data presented at the 2022 American Society of Clinical Oncology Annual Meeting show patients who are 55 or older with low-grade luminal A breast cancer may benefit from post-surgery endocrine therapy only, omitting radiation therapy due to their low risk of recurrence.
The LUMINA study enrolled 500 patients with luminal A breast cancer whose biomarker screening results showed that 13.25% or less of the tumor cells had the protein marker Ki67, a biomarker associated with cancer cell growth. Participants underwent breast conserving surgery followed by endocrine therapy for five years. They did not receive radiation therapy. Results showed overall survival was 97.2% with only 2.3% chance of local recurrence.
"It is important to note that not all early stage breast cancer patients are the same. Patients should have a tailored discussion with their radiation oncologist regarding their unique risk benefit ratio in determining their radiation treatment plan."- Dr. Kamran Ahmed, Radiation Oncologist, @KAhmedMD
“LUMINA is an important clinical trial that looks at the role of omission of radiotherapy in low risk, early stage breast cancer. It follows the results of PRIME II and CALGB 9343 looking specifically at Luminal A patients. Five-year data shows a low risk of recurrence with adjuvant endocrine therapy alone. While we wait for further data maturation, it is important to note that not all early stage breast cancer patients are the same. Patients should have a tailored discussion with their radiation oncologist regarding their unique risk benefit ratio in determining their radiation treatment plan,” said Dr. Kamran Ahmed, a radiation oncologist at Moffitt Cancer Center.