Secondary sarcomas
after radiotherapy for breast cancer : Sustained risk and poor
survival Carlos M. Mery, Suzanne George, Monica M. Bertagnolli, Chandrajit P. Raut Dana-Farber Cancer Institute, Harvard Medical School, Cancer 2009; Volume 115 Issue 18, Pages 4055 - 4063
Radiotherapy (RT) has
been a risk factor for development of
soft tissue sarcomas (STS).
The objective of the current study was to quantify the risk of STS
after RT and surgery for breast cancer (BCa), assess time trends,
and compare long-term survival of patients with RT-associated and
non-RT-associated
angiosarcoma (AS) using the Surveillance, Epidemiology, and
End Results (SEER) database. RT
patients had a higher incidence of all STS (31 vs 22 per 100,000
person-years; HR), AS (HR, 7.6), and malignant fibrous histiocytomas
(MFH) (HR, 2.5). RT remained a significant predictor after
adjustment for covariates (HR, 1.4; 95% CI, 1.2-1.7). Partial
mastectomies (HR, 7.1; 95% CI, 3.2-16), RT (HR, 2.2; 95% CI,
1.1-4.3), and lymph node dissections (HR, 2.6; 95% CI, 1.3-5) were
found to be independent risk factors for AS. The
hazard of STS after RT
peaked at 10 years, reaching the non-RT hazard at approximately 23
years. The 5-year survival for STS was 38%. There was no
difference in survival noted between RT-induced and non-RT-induced
AS. |