A recent study published in the New England Journal of Medicine raises significant questions about the necessity of radiation therapy for certain breast cancer patients. The findings indicate that for women with early-stage breast cancer who have undergone lymph node surgery and mastectomy, radiation may not improve survival rates. This study focused on patients at intermediate risk, specifically those with Stage II cancer, and its long-term follow-up included data from approximately 1,600 women over a period of 10 years.
The research revealed that among the participants, only 29 women experienced recurrent cancer in the chest area within a decade, even without radiation treatment. Dr. Chirag Shah, Chair of the Department of Radiation Oncology at the Allegheny Health Network Cancer Institute, emphasized the significance of this trial, stating, “This is an important trial in the management of breast cancer patients. This will help define the standard of care for appropriately selected patients.”
Despite the promising findings, Dr. Shah noted a major limitation of the study. He pointed out that most patients had undergone axillary lymph node dissections, a factor that may diminish the perceived benefits of radiation therapy. He highlighted that current clinical practices often opt for radiation therapy instead of dissection based on other trials, such as the AMAROS trial.
The study design included two groups: one receiving radiation therapy post-surgery and the other not. After a decade, both groups reported nearly identical survival rates of 81%. While the data showed comparable survival rates, it did not address whether radiation prevented cancer recurrence or metastasis to other body parts.
Radiation therapy is a common treatment for cancer, using high-energy beams to damage the DNA of cancer cells, effectively stopping their growth. However, it can also impact healthy cells, which may recover from treatment. Historically, the combination of chemotherapy and radiation has been the standard approach, supported by previous trials that demonstrated improved survival rates.
Dr. Shah elaborated, “For example, with regards to radiation following mastectomy, previous randomized trials showed not only a reduction in recurrence but improvement in survival.” He clarified that radiation is localized to the breast or chest wall, contrasting it with systemic chemotherapy that targets the entire body.
Despite advancements in radiation techniques that have reduced side effects, potential risks remain. “Short-term side effects can include fatigue and skin irritation,” Dr. Shah explained. “Long-term side effects can include skin changes, arm swelling, and in very rare cases, a second cancer.” He also noted that radiation can complicate breast reconstruction efforts.
According to the American Cancer Society, breast cancer remains the most prevalent cancer among women in the United States, following skin cancer. Approximately 1 in 8 women will be diagnosed with invasive breast cancer in their lifetime. Recent advancements in targeted therapy have led to shorter treatment durations and a reevaluation of radiation therapy for women at lower risk of cancer recurrence.
While the current study suggests that some women at intermediate risk may forego radiation, medical professionals maintain that it remains essential for those at higher risk. Dr. Shah emphasized the importance of shared decision-making between patients and their oncologists. “For patients matching the trial eligibility criteria, they should be informed that radiation therapy has been shown in this study to not improve survival, though there may be an increase in chest wall recurrences,” he stated, underscoring the need for tailored treatment plans based on individual patient circumstances.
