Background: Reported incidence rates of oesophageal adenocarcinoma (OAC) in Barrett's oesophagus (BO) vary widely. As the effectiveness of BO surveillance is crucially dependent on this rate, its clarification is essential.
Methods: To estimate the rate of malignant progression in patients with BO, all patients with a first diagnosis of BO with no dysplasia (ND) or low-grade dysplasia (LGD) between 1991 and 2006 were identified in the Dutch nationwide registry of histopathology (PALGA). Follow-up data were evaluated up to November 2007.
Results: 42 207 patients with BO were included; 4132 (8%) of them had LGD. Re-evaluation endoscopies at least 6 months after initial diagnosis were performed in 16 365 patients (39%), who were significantly younger than those not re-examined (58+/-13 vs 63+/-16 years, p<0.001). These patients were followed-up for a total of 78 131 person-years, during which 666 (4%) high-grade dysplasia (HGD)/OACs occurred, affecting 4% of the surveillance patient population (mean age: 69+/-12 years, 76% male). After excluding HGD/OAC cases detected within 1 year after BO diagnosis (n=212, 32%), incidence rates per 1000 person-years were 4.3 (95% CI 3.4 to 5.5) for OAC and 5.8 (95% CI 4.6 to 7.0) for HGD/OAC combined. Risk factors for HGD/OAC were increased age (eg, >75 years HR 12; 95% CI 8.0 to 18), male sex (2.01; 1.68 to 2.60) and presence of LGD at baseline (1.91; 1.53 to 2.40).
Conclusion: In this largest reported cohort of unselected patients with BO, the annual risk of OAC was 0.4%. Male sex, older age and LGD at diagnosis are independent predictors of malignant progression, and should enable an improved risk assessment in BO.