Background: The interval between the onset of Barrett's oesophagus (BO) and oesophageal adenocarcinoma (OAC) can be termed the incubation period. However, the unrecorded onset of BO precludes its direct observation.
Methods: Determining the range of intervals between BO diagnosis and OAC within the longest observational BO follow-up study. Exclusion criteria were presence of high-grade dysplasia (HGD) or OAC at baseline, death within <2 years of BO diagnosis, oesophagectomy without HGD/OAC and loss to follow-up. A total of 133 patients (M/F 73/60) were taken into account.
Results: In 1967 person years of follow-up there were 13 cases of HGD/OAC, (0.66% p.a.; 95% CI 0.58-0.74), 96 patients died without HGD/OAC and 24 survived without HGD/OAC. The mean intervals between BO diagnosis and either HGD/OAC, death or end of follow-up were 10.8, 12.6 and 25.5 years, respectively, and the mean ages at endpoint were 72.5, 80.0 and 68.3 years, respectively. The survivors without HGD/OAC had a lower age at BO diagnosis (mean 42.8 vs 61.2 and 67.4 years, P<0.001). Baseline presence of low-grade dysplasia was associated with progression to HGD/OAC (log rank P<0.001).
Conclusion: The Rotterdam BO follow-up cohort revealed a long incubation period between onset of BO and development of HGD/OAC, in patients without HGD/OAC at baseline as illustrated by 24 patients diagnosed with BO at a young age and followed for a mean period of 25.5 years. Their tumour-free survival established a minimum incubation period, suggesting a true incubation period of three decades or more.