Radiation-induced sarcoma of the breast: a systematic review

INTRODUCTION

Radiation-induced sarcoma (RIS) is a rare, aggressive malignancy. Breast cancer survivors treated with radiotherapy constitute a large fraction of RIS patients. To evaluate evidenced-based practices for RIS treatment, we performed a systematic review of the published English-language literature.

METHODS

We performed a systematic keyword search of PubMed for original research articles pertaining to RIS of the breast. We classified and evaluated the articles based on hierarchical levels of scientific evidence.

RESULTS

We identified 124 original articles available for analysis, which included 1,831 patients. No randomized controlled trials involving RIS patients were found. We present the best available evidence for the etiology, comparative biology to primary sarcoma, prognostic factors, and treatment options for RIS of the breast.

CONCLUSION

Although the evidence to guide clinical practice is limited to single institutional cohort studies, registry studies, case-control studies, and case reports, we applied the available evidence to address clinically relevant questions related to best practice in patient management. Surgery with widely negative margins remains the primary treatment of RIS. Unfortunately, the role of adjuvant and neoadjuvant chemotherapy remains uncertain. This systematic review highlights the need for additional well-designed studies to inform the management of RIS.

Radiation-Induced Sarcoma Following Treatment of Breast Cancer

BACKGROUND: Radiation therapy (XRT) is an important modality in the treatment of cancer, and XRT is now commonly utilized in the treatment of early-stage breast cancer. However, its use has occasionally resulted in the development of secondary malignancies. We present a critical review of radiation-induced sarcoma (RIS) that develops after irradiation for the treatment of breast cancer. METHODS: The case of a patient who developed sarcoma after radiation for breast cancer is presented, and current literature on RIS is reviewed. The role of XRT in the development of RIS is examined, and the evaluation and treatment of these malignancies are reviewed. Results: RIS occurs in 0.2% of patients following treatment of breast cancer. The role of radiation in the development of RIS has been clearly demonstrated. Clinical presentation varies, and diagnosis is commonly delayed. Treatment consists of wide surgical excision. The role of chemotherapy is controversial. CONCLUSIONS: The occurrence of RIS following treatment of breast cancer is rare. Its development has an average latency of over 10 years and likely correlates with the dose and technique of the radiation treatment. The prognosis of patients with RIS following treatment for breast cancer is poor predominantly due to a delay in diagnosis. However, the benefit derived by breast cancer patients from XRT far outweighs the risk of RIS and should not affect the decision to treat these patients with this modality.