Objective: This study was undertaken to assess a potential relationship between idiopathic deep venous thrombosis (DVT) and occult cancer.
Design: Prospective study with a 2-year follow-up.
Setting: The Angiology Unit of the First Department of Surgery, University of Athens, Greece, a tertiary referral centre.
Subjects: Two hundred and ninety-three patients with a first episode of venographically or Doppler-proved DVT were included in the study, of whom 264 were followed up for 2 years.
Interventions: After an initial extensive diagnostic workup, including routine blood counts and chemistries, erythrocyte sedimentation rate, CEA levels, chest X-ray and abdominopelvic CT scan, all patients were closely followed up and periodically examined.
Main outcome measures: The incidence of cancer amongst patients with idiopathic and secondary DVT, and the validity of our screening programme.
Results: Cancer was diagnosed in 21 out of 84 patients with idiopathic DVT (25%) as compared with eight out of 202 patients with secondary DVT (4%). In 22 out of the 29 cases, cancer was detected during the initial admission, and the remaining seven cases were detected during follow-up. Cancer was diagnosed in 15 asymptomatic, healthy individuals, but only in seven of them was the diagnosis made by CT scan.
Conclusion: Occult cancer is fairly common in patients with idiopathic DVT, but the routine use of extensive diagnostic studies for its detection remains to be validated by further prospective studies.