title: Therapy-related myelodysplastic syndrome following primary breast cancer.
abstract: Therapy-related myelodysplastic syndrome (t-MDS) is a serious clinical disease occurring after breast cancer treatment.
  
  
  
  A cohort of 11,684 invasive breast cancer (BC) patients from 1990-2014 were followed for incidence of t-MDS through institutional and the Surveillance, Epidemiology and End Results (SEER) Program registries. t-MDS cases were identified using ICD-O SEER registry codes, pathology and chart reports. Treatment, cytogenetics, and time from BC diagnosis to t-MDS and t-MDS diagnosis to last follow up or death were obtained. Incidence rate ratios were calculated using SEER national incidence rates for comparison.
  
  
  
  27 cases of t-MDS post BC treatment were confirmed. 96% of cases were breast cancer stage I-II at diagnosis. All patients had received radiation treatment and 59% received adjuvant chemotherapy. Two patients were alive with no evidence of disease after treatment with stem cell transplantation (age 33 and 46). t-MDS incidence was 30 times the expected population rate among patients <55 years (RR 31.8, 95% CI 15.0, 60.8) with shorter time from t-MDS diagnosis to death (median survival time: <55: 8 months, 55-74: 26 months, 75+: 23 months).
  
  
  
  We found elevated t-MDS risk especially among younger BC patients with stem cell transplantation the only observed curative treatment.
authors.affiliation: HealthStat Consulting, Inc., Seattle, WA, United States; University of Washington, Department of Epidemiology, Seattle, WA, United States. Electronic address: jmalmgren@seanet.com.
authors.forename: Judith A
authors.initials: JA
authors.lastname: Malmgren
authors.affiliation: University of Illinois at Chicago, Center for Pharmacoepidemiology and Pharmacoeconomic Research, Chicago, IL, United States.
authors.forename: Gregory S
authors.initials: GS
authors.lastname: Calip
authors.affiliation: PhenoPath Laboratories, Seattle, WA, United States.
authors.forename: Shawna M
authors.initials: SM
authors.lastname: Pyott
authors.affiliation: Swedish Cancer Institute, Department of Oncology, Seattle, WA, United States.
authors.forename: Mary K
authors.initials: MK
authors.lastname: Atwood
authors.affiliation: Swedish Cancer Institute, Department of Oncology, Seattle, WA, United States.
authors.forename: Henry G
authors.initials: HG
authors.lastname: Kaplan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000150:complications* / Q000453:epidemiology / Q000628:therapy; D005260:Female; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D009190:Myelodysplastic Syndromes / Q000209:etiology* / Q000401:mortality; D016609:Neoplasms, Second Primary; D012042:Registries; D018426:SEER Program; D033581:Stem Cell Transplantation / Q000009:adverse effects
keywords: Breast cancer; Prognosis; Survival; Therapy-related myelodysplasia; Therapy-related myeloid neoplasm; t-MDS