Screening for Occult Cancer in Unprovoked Venous Thromboembolism

N Engl J Med. 2015 Aug 20;373(8):697-704. doi: 10.1056/NEJMoa1506623. Epub 2015 Jun 22.

Abstract

Background: Venous thromboembolism may be the earliest sign of cancer. Currently, there is a great diversity in practices regarding screening for occult cancer in a person who has an unprovoked venous thromboembolism. We sought to assess the efficacy of a screening strategy for occult cancer that included comprehensive computed tomography (CT) of the abdomen and pelvis in patients who had a first unprovoked venous thromboembolism.

Methods: We conducted a multicenter, open-label, randomized, controlled trial in Canada. Patients were randomly assigned to undergo limited occult-cancer screening (basic blood testing, chest radiography, and screening for breast, cervical, and prostate cancer) or limited occult-cancer screening in combination with CT. The primary outcome measure was confirmed cancer that was missed by the screening strategy and detected by the end of the 1-year follow-up period.

Results: Of the 854 patients who underwent randomization, 33 (3.9%) had a new diagnosis of occult cancer between randomization and the 1-year follow-up: 14 of the 431 patients (3.2%) in the limited-screening group and 19 of the 423 patients (4.5%) in the limited-screening-plus-CT group (P=0.28). In the primary outcome analysis, 4 occult cancers (29%) were missed by the limited screening strategy, whereas 5 (26%) were missed by the strategy of limited screening plus CT (P=1.0). There was no significant difference between the two study groups in the mean time to a cancer diagnosis (4.2 months in the limited-screening group and 4.0 months in the limited-screening-plus-CT group, P=0.88) or in cancer-related mortality (1.4% and 0.9%, P=0.75).

Conclusions: The prevalence of occult cancer was low among patients with a first unprovoked venous thromboembolism. Routine screening with CT of the abdomen and pelvis did not provide a clinically significant benefit. (Funded by the Heart and Stroke Foundation of Canada; SOME ClinicalTrials.gov number, NCT00773448.).

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Breast Neoplasms / diagnosis
  • Diagnostic Errors
  • Early Detection of Cancer / methods*
  • Female
  • Follow-Up Studies
  • Humans
  • Incidence
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Neoplasms, Unknown Primary / complications
  • Neoplasms, Unknown Primary / diagnosis
  • Neoplasms, Unknown Primary / diagnostic imaging*
  • Pelvis / diagnostic imaging
  • Prostatic Neoplasms / diagnosis
  • Radiography, Abdominal
  • Tomography, X-Ray Computed*
  • Uterine Cervical Neoplasms / diagnosis
  • Venous Thromboembolism / etiology*

Associated data

  • ClinicalTrials.gov/NCT00773448