Incomplete Goblet Cell Maturation: A Distinctive Form of Flat Dysplasia in IBD.
Lihui Qin, Hongfa Zhu, Mohamad Raoufi, Noam Harpaz. Mount Sinai School of Medicine, New York, NY
Background: Nuclear atypia is a hallmark of dysplasia in inflammatory bowel disease (IBD), however, a notable exception is incomplete goblet cell maturation (IGCM), a type of dysplasia characterized by unexplained absence or near-absence of goblet cells, uniformly eosinophilic cytoplasm, minimal or absent nuclear atypia in most cases, and near-normal crypt architecture without a polypoid component. Because IGCM is underrecognized due to the lack of nuclear atypia and resemblance to regenerative mucosa, we evaluated its association with conventional dysplasia and its significance as a risk factor for colorectal cancer.
Design: Our GI Database was queried for a diagnosis of IGCM between 1994-2010. The diagnoses were correlated with synchronous and metachronous dysplasia using chi-square statistics. IGCM was usually graded indefinite for dysplasia (IND), mainly due to the difficulty of excluding regenerative change with certainty, however, diagnoses of indefinite probably negative (IND-N) or probably positive (IND-P) were rendered when regeneration seemed more or less likely based on the inflammatory surroundings. A minority of cases were interpreted as low-grade dysplasia (LGD) or high-grade dysplasia (HGD) based on criteria for conventional dysplasia.
Results: IGCM was reported in 80 patients (51 males, 29 females, ages 22-81y). It accounted for 4.7% of all biopsies with definite or indefinite dysplasia (9% IND-N, 52% IND, 19% IND-P, 17% LGD, and 2% HGD). A significant correlation was observed between the grade of dysplasia assigned to IGCM and the presence of synchronous conventional dysplasia: no biopsies with conventional dysplasia were observed in the same procedure as IND-N compared to 29% in procedures with IGCM of grade IND or higher (p=0.008). Among 56% of patients with IGCM who had undergone previous biopsies, no significant differences were noted in the prevalence of previous dysplasia.
Among 56 IGCM patients with long-term follow-up, LGD and carcinoma were more prevalent among 48 with IGCM graded IND or higher (15 and 10, respectively) than among 8 graded IND-N (0 and 0, respectively), though statistically insignificant. Among these 56 patients, IGCM persisted in subsequent procedures in 13 (23%). Of 21 patients who had IGCM as their first and only dysplastic finding and adequate follow-up, 6 (29%) developed conventional dysplasia including 4 LGD, 1 HGD and 1 carcinoma.
Conclusions: IGCM, a distinctive type of flat dysplasia in IBD, should be considered when an unexplained absence of goblet cells is noted in the setting of IBD and should be managed similarly to conventional types of dysplasia.
Monday, February 28, 2011 11:45 AM
Platform Session: Section E, Monday Morning