Gallbladder dysplasia in patients with familial adenomatous polyposis

Abstract

Patients with familial adenomatous polyposis (FAP) are at increased risk of dying from upper gastrointestinal malignancy'.Common tumours are adenoma and adenocarcinoma involving the duodenum and ampulla of Vater. O f patients with FAP, 90 per cent have adenomas in the duodenum, with marked periampullary clustering, but the incidence of adenoma or dysplasia within the biliary tree itself is unknown and diilicult to assess. There have been case reports of polyps and cancer in the gallbladder2, bile ducts3 and liveP, supporting the hypothesis that mucosa exposed to bile in patients with FAP is at risk of undergoing adenomatous and malignant transformation.The prevalence of dysplasia in the gallbladder of a group of patients with FAP who had undergone cholecystectomy is reported. Patients and methodsThe St Mark's Polyposis Registry keeps a record of all patients with FAP who have undergone cholecystectomy. The blocks and slides of patients undergoing cholecystectomy at St Mark's Hospital were retrieved. Of those not undergoing treatment at St Mark's, if the year and place of the operation were known, a letter was sent to the pathology department requesting copies of the slides and reports. When the year was known but the hospital was not, local hospitals were approached. When no details were available and the patient had died, no further action was taken. There was only a small portion of gallbladder available for histological assessment as the whole organ was not retained by any pathology department.Each set of slides was reviewed by a single histopathologist (I.C.T.) for epithelial dysplasia, microadenoma, adenomatous polyps and carcinoma. Whenever possible, the stage of duodenal polyposis and histology assessed at upper gastrointestinal endoscopy, together with Paper accepted 7 May 1993 the presence or absence of gallstones, were also noted. The Spigelman stage of duodenal polyposis was calculated using scores for the number, size, degree of dysplasia and histological architecture of polyps, and was graded from stage 0 to IV, where stage IV represents severe disease'. ResultsA total of 25 cholecystectomies in patients with FAP were registered between 1965 and 1991. The mean age of patients was 48 years and 16 were female. Ten operations were performed at St Mark's, ten hospitals supplied slides and no slides were available in five.Gallbladder dysplasia was seen in eight of 20 patients, comprising two examples of flat epithelial dysplasia, four of microadenoma and two of adenomatous polyps (3 x 2 cm and 0.5 x 0.5 cm in size). One adenoma was villous with moderate dysplasia, the other tubular with mild dysplasia The remaining 12 specimens showed no epithelial abnormality.Age, sex, presence of gallstones, pathology department (St Mark's versus elsewhere) and the stage of duodenal polyposis were not related to the finding of gallbladder dysplasia (Table I). DiscussionIn this series of 20 gallbladder specimens from patients with FAP, 40 per cent had epithelial dysplasia. This must be an underestimate of the true incide...

Gastrointestinal Polyposis Syndromes

“…Extra-intestinal malignancies that have been associated with FAP, include thyroid, pancreatic [18], biliary tree [19,20], hepatoblastoma [21], and medulloblastoma [22]. Thyroid cancer, predominantly papillary carcinoma, can be found in 1-2% of FAP patients.…”