A team from Rochester, Minnesota, USA, determined if a limited extent of high-grade dysplasia (HGD) in Barrett's esophagus has the same potential for cancer as diffuse high-grade dysplasia.
A retrospective cohort study was performed to assess the risk of developing adenocarcinoma in relationship to the extent of HGD found on endoscopic surveillance.
The extent of HGD was defined as focal if cytologic and/or architectural changes of HGD were limited to a single focus of 5 or fewer crypts. It was defined as diffuse if more than 5 crypts were involved in a single biopsy specimen or if HGD involved more than one biopsy fragment.
The relative risk of cancer was assessed using a Cox proportional hazard model, and cancer-free survival was determined using survival curves.
|Cancer-free survival rates at 1 and 3 years:|
Focal HGD: 93% and 86%
Diffuse HGD: 62% and 44%
67 patients with diffuse HGD and 33 with focal HGD satisfied selection criteria were enrolled in the study.
The researchers found that cancer-free survival rates at 1 and 3 years were 93% and 86% for focal HGD, compared with 62% and 44% for diffuse HGD.
On univariate analysis, extent of HGD (relative risk [RR], 5.4), nodularity on endoscopy (RR, 4.0), and lack of acid suppression (RR, 2.5) were associated with an increased risk of esophageal adenocarcinoma.
Diffuse HGD was found to have a 3.7-fold increase in the risk of esophageal cancer, compared with focal HGD on multivariate analysis.
Navtej S. Buttar, of the Mayo Clinic and Graduate School of Medicine, concluded on behalf of the researchers, "Patients with focal high-grade dysplasia are less likely to have cancer during the first year after diagnosis or on subsequent follow-up compared with diffuse high-grade dysplasia."