title: Incidence of venous thromboembolism in the year before the diagnosis of cancer in 528,693 adults.
abstract: BACKGROUND
  It is unclear how frequently unprovoked venous thromboembolism (VTE) reflects the presence of an occult cancer.
  
  
  METHODS
  The California Cancer Registry was used to identify diagnosed cases of 19 common malignancies during a 6-year period. Cases were linked to a hospital discharge database to identify incident VTE events in the year before the cancer diagnosis date. The standardized incidence ratio (SIR) of unprovoked VTE was determined by using the age-, race-, and sex-specific incidence rates in California.
  
  
  RESULTS
  Among 528,693 cancer cases, 596 (0.11%) were associated with a diagnosis of unprovoked VTE within 1 year of the cancer diagnosis, compared with 443.0 expected cases (SIR, 1.3; 95% confidence interval, 1.2-1.5; P<.001). Among cases with metastatic-stage cancer, the SIR was 2.3 (95% confidence interval, 2.0-2.6; P<.001), whereas for all other stages, the SIR was 1.07 (95% confidence interval, 0.97-1.18; P = .09). The incidence of preceding VTE was increased over that expected only during the 4-month period immediately preceding the cancer diagnosis date (P<.001). Only 7 cancer types were associated with a significantly elevated SIR: acute myelogenous leukemia; non-Hodgkin lymphoma; and renal cell, ovarian, pancreatic, stomach, and lung cancer (SIR range, 1.8-4.2).
  
  
  CONCLUSIONS
  In the year preceding the diagnosis of cancer, the number of cases with unprovoked VTE was modestly higher than expected, and almost all of the unexpected VTE cases were associated with a diagnosis of metastatic-stage cancer within 4 months. Given the timing and advanced stage of the unexpected cases, it is unlikely that earlier diagnosis of these cancers would have significantly improved long-term survival.
authors.affiliation: Departments of Internal Medicine, Medicine, Medicine and Statistics, and Public Health Sciences, University of California Davis, Sacramento, CA 95817, USA. rhwhite@ucdavis.edu
authors.forename: Richard H
authors.initials: RH
authors.lastname: White
authors.forename: Helen K
authors.initials: HK
authors.lastname: Chew
authors.forename: Hong
authors.initials: H
authors.lastname: Zhou
authors.forename: Arti
authors.initials: A
authors.lastname: Parikh-Patel
authors.forename: David
authors.initials: D
authors.lastname: Harris
authors.forename: Danielle
authors.initials: D
authors.lastname: Harvey
authors.forename: Theodore
authors.initials: T
authors.lastname: Wun
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000453:epidemiology; D002140:California / Q000453:epidemiology; D002292:Carcinoma, Renal Cell / Q000453:epidemiology; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000453:epidemiology; D015897:Comorbidity; D005260:Female; D006801:Humans; D015994:Incidence; D007680:Kidney Neoplasms / Q000453:epidemiology; D007951:Leukemia, Myeloid / Q000453:epidemiology; D008175:Lung Neoplasms / Q000453:epidemiology; D008228:Lymphoma, Non-Hodgkin / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000453:epidemiology*; D010051:Ovarian Neoplasms / Q000453:epidemiology; D010190:Pancreatic Neoplasms / Q000453:epidemiology; D011471:Prostatic Neoplasms / Q000453:epidemiology; D013274:Stomach Neoplasms / Q000453:epidemiology; D013997:Time Factors; D020246:Venous Thrombosis / Q000453:epidemiology*