Recent research challenges the long-standing role of radiation therapy in the treatment of breast cancer. A study published in the New England Journal of Medicine has revealed that radiation may not be necessary for certain patients with early-stage breast cancer who have undergone lymph node surgery and mastectomy while also receiving anti-cancer medications.
The study followed a cohort of 1,600 women diagnosed with intermediate-risk breast cancer, specifically Stage II, which included those with affected lymph nodes as well as aggressive tumors without lymph node involvement. Over a follow-up period of 10 years, the research found no significant difference in survival rates between patients who received radiation therapy and those who did not. Both groups recorded a survival rate of 81%.
Dr. Chirag Shah, chair of the Department of Radiation Oncology at the Allegheny Health Network Cancer Institute, emphasized the importance of this trial in redefining treatment standards for breast cancer patients. He noted that the majority of participants had undergone axillary lymph node dissections, a procedure that may diminish the apparent benefits of radiation therapy. “This will help define the standard of care for appropriately selected patients,” he stated.
The study’s design involved randomly assigning half of the patients to receive radiation therapy after surgery, while the other half did not. Notably, despite the lack of radiation, only 29 women experienced recurrent cancer in the chest area over the decade-long study. While these results demonstrate similar survival rates, they do not clarify whether radiation prevents cancer recurrence or the spread of cancer to other parts of the body.
Radiation therapy operates by delivering high-energy beams or particles aimed at damaging the DNA of cancer cells, which inhibits their growth and leads to cell death. While effective, this treatment can also impact healthy cells, although they typically recover from the exposure. Traditionally, radiation and chemotherapy have been used in tandem due to past studies indicating their effectiveness in improving patient outcomes.
Dr. Shah explained, “Previous randomized trials showed not only a reduction in recurrence but an improvement in survival.” He differentiated between localized radiation therapy, which targets specific areas such as the breast or chest wall, and systemic chemotherapy, which is administered through intravenous means or orally to affect the entire body.
The potential side effects associated with radiation therapy can be both short-term and long-term. Short-term effects may include fatigue and skin irritation, while long-term risks encompass skin changes, arm swelling (lymphedema), and, in rare cases, the development of secondary cancers. Modern advancements in radiation techniques have reduced the incidence of these side effects, yet the treatment may complicate subsequent breast reconstruction efforts.
Breast cancer remains a significant health issue, as evidenced by data from the American Cancer Society, which indicates that approximately 1 in 8 women in the United States will be diagnosed with invasive breast cancer in their lifetime. Recent developments in radiation treatment have led to shorter therapy durations. Physicians are increasingly considering the risks and benefits of radiation, particularly for women identified as low risk for recurrence.
While this new study suggests that some patients at intermediate risk may forgo radiation therapy, Dr. Shah advises caution. He stated, “For patients matching the trial eligibility criteria, they should be informed that radiation therapy has been shown in this study to not improve survival. However, there may be an increase in chest wall recurrences.” He also highlighted that many women who do not have lymph node dissections might still require radiation based on other clinical trial findings.
Ultimately, the focus remains on shared decision-making between patients and their oncologists to determine the best course of action tailored to individual circumstances.
