title: Second primary malignancy risk in thyroid cancer survivors: a systematic review and meta-analysis.
abstract: OBJECTIVE
  To determine the risk of second primary malignancies (SPMs) in thyroid cancer survivors.
  
  
  METHODS
  We performed a systematic review and meta-analysis examining the standardized incidence ratios (SIRs) of SPMs in thyroid cancer survivors (compared to individuals without thyroid cancer). Two independent reviewers screened citations and reviewed all full-text papers deemed potentially relevant. Final consensus was reached on inclusion of papers in the review. Data were pooled using fixed effects models.
  
  
  RESULTS
  Thirteen full-text papers were included. The incidence of SPMs in thyroid cancer survivors was increased with an SIR of 1.20 (95% confidence interval 1.17, 1.24) (based on pooled data from six studies of 70,844 thyroid cancer survivors). The SIR of the following SPMs was significantly increased: salivary gland, stomach, colon/colorectal, breast, prostate, kidney, brain/central nervous system, soft tissue sarcoma, non-Hodgkin's lymphoma, multiple myeloma, leukemia, bone/joints, and adrenal. A significantly reduced risk of lung and cervical cancers was observed.
  
  
  CONCLUSIONS
  Thyroid cancer survivors are at increased risk of SPMs, which may be related to disease-specific treatments or genetic predisposition.
authors.affiliation: Endocrinology, Stanford University, Palo Alto, California, USA.
authors.forename: Shoba
authors.initials: S
authors.lastname: Subramanian
authors.forename: David P
authors.initials: DP
authors.lastname: Goldstein
authors.forename: Luciana
authors.initials: L
authors.lastname: Parlea
authors.forename: Lehana
authors.initials: L
authors.lastname: Thabane
authors.forename: Shereen
authors.initials: S
authors.lastname: Ezzat
authors.forename: Irada
authors.initials: I
authors.lastname: Ibrahim-Zada
authors.forename: Sharon
authors.initials: S
authors.lastname: Straus
authors.forename: James D
authors.initials: JD
authors.lastname: Brierley
authors.forename: Richard W
authors.initials: RW
authors.lastname: Tsang
authors.forename: Amiram
authors.initials: A
authors.lastname: Gafni
authors.forename: Lorne
authors.initials: L
authors.lastname: Rotstein
authors.forename: Anna M
authors.initials: AM
authors.lastname: Sawka
mesh_terms: D017024:Chemotherapy, Adjuvant / Q000009:adverse effects; D020022:Genetic Predisposition to Disease; D006801:Humans; D015994:Incidence; D016609:Neoplasms, Second Primary / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics; D018714:Radiotherapy, Adjuvant / Q000009:adverse effects; D012307:Risk Factors; D013964:Thyroid Neoplasms