• Int. J. Radiat. Oncol. Biol. Phys. · Oct 2019

    Comparative Study

    Elevated Risk of Radiation Therapy-Associated Second Malignant Neoplasms in Young African-American Women Survivors of Stage I-IIIA Breast Cancer.

    • Liyi Xie, Xuhui Bao, Tianji Cai, Susan G Silva, Jinli Ma, Zhen Zhang, Xiaomao Guo, and Lawrence B Marks.
    • Department of Radiation Oncology, Fudan University Shanghai Cancer Center, Shanghai, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China.
    • Int. J. Radiat. Oncol. Biol. Phys. 2019 Oct 1; 105 (2): 275-284.

    PurposeTo estimate the effect of radiation therapy (RT) on nonbreast second malignant neoplasms (SMNs) in young women survivors of stage I-IIIA breast cancer.Methods And MaterialsWomen aged 20 to 44 years who received a diagnosis of stage I-IIIA breast cancer (1988-2008) were identified in the Surveillance, Epidemiology, and End Results 9 registries. Bootstrapping approach and competing-risk proportional hazards models were used to evaluate the effect of RT on nonbreast SMN risk. The analysis was repeated in racial subgroups. Radiotolerance score analysis of normal airway epithelium was performed using Gene Expression Omnibus (GEO) data sets.ResultsWithin records of 30,003 women with primary breast cancer, 20,516 eligible patients were identified, including 2,183 African Americans (AAs) and 16,009 Caucasians. The 25-year cumulative incidences of SMN were 5.2% and 3.6% (RT vs no-RT) for AAs, with 12.8-year and 17.4-year (RT vs no-RT) median follow-up (hazard ratio [HR] = 1.81; 95% bootstrapping confidence interval [BCI], 1.02-2.50; P < .05), respectively, and 6.4% and 5.9% (RT vs no-RT) for Caucasians with 14.3-year and 18.1-year (RT vs no-RT) median follow-up (HR = 1.10; 95% BCI, 0.61-1.40; P > .05), respectively. The largest portion of excess RT-related SMN risk was lung cancer (AA: HR = 2.08, 95% BCI, 1.02-5.39, P < .05; Caucasian: HR = 1.50, 95% BCI, 0.84-5.38, P > .05). Subpopulation Treatment Effect Pattern Plot (STEPP) analysis revealed higher post-RT nonbreast SMN risk in those 20 to 44 years of age, with larger HRs for RT in AAs. Radiotolerance score (RTS) of normal airway epithelium from young AA women was significantly lower than that from young Caucasian women (P = .038).ConclusionsWith a projected 25-year follow-up, RT is associated with elevated risk of nonbreast SMNs, particularly second lung cancer, in young women survivors of stage I-IIIA breast cancer. Nonbreast SMNs associated with RT are higher in AA women than Caucasian women.Copyright © 2019 Elsevier Inc. All rights reserved.

      Pubmed     Full text   Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…