Late complications of radiation therapy for breast cancer: evolution in techniques and risk over time

Abstract

Radiation therapy in combination with surgery, chemotherapy, and endocrine therapy as indicated, has led to excellent local and distant control of early stage breast cancers. With the majority of these patients surviving long term, mitigating the probability and severity of late toxicities is vital. Radiation to the breast, with or without additional fields for nodal coverage, has the potential to negatively impact long term cosmetic outcome of the treated breast as well as cause rare, but severe, complications due to incidental dosage to the heart, lungs and contralateral breast. The long-term clinical side-effects of breast radiation have been studied extensively. This review aims to discuss the risk of developing late complications following breast radiation and how modern techniques can be used to diminish these risks.

Overview of Breast Cancer and Implications of Overtreatment of Early-Stage Breast Cancer: An Indian Perspective

“…40 Incidental radiation exposure of the heart, lungs, and contralateral breast may occasionally result in complications in these organs, especially in patients who receive radiotherapy after mastectomy. 39 , 41 …”

Adjuvant radiation therapy alone is associated with improved overall survival compared to hormonal therapy alone in older women with estrogen receptor positive early stage breast cancer

“…By comparison, modern radiotherapy regimens allow for the completion of whole breast irradiation in only 3-4 weeks with low rates of toxicity. 11,[19][20][21] This study has several important limitations. It is a retrospective analysis using data from participating institutions, which mainly represent hospital-based practices accredited by the American College of Surgeons Commission on Cancer.…”

“…With regards to contralateral breast cancer, it has been demonstrated that the most important prognostic factor is age at first diagnosis, 18 again suggesting that this benefit of endocrine therapy is more important in the younger patient population. By comparison, modern radiotherapy regimens allow for the completion of whole breast irradiation in only 3‐4 weeks with low rates of toxicity 11,19‐21 …”

Combined Photothermal and Ionizing Radiation Sensitization of Triple-Negative Breast Cancer Using Triangular Silver Nanoparticles

“…Techniques currently employed to help minimize exposure of normal breast and lymph tissue to radiation include intensity modulated radiation therapy, deep-inspiration breath hold, and hypofractionation, but risk of acute and late adverse events are still considerable. 18 There is a lack of evidence demonstrating that accelerated courses using high dose radiation improve long-term survival outcomes for breast cancer patients, including those with evidence of residual disease after lumpectomy. 19 Partial breast irradiation may be an option for some women, but this does not reduce treatment duration and has not been shown to improve patient outcomes compared to whole breast irradiation.…”