title: Incidentally detected gallbladder polyps: is follow-up necessary?--Long-term clinical and US analysis of 346 patients.
abstract: OBJECTIVE
  To determine the natural history of gallbladder (GB) polyps incidentally detected at ultrasonography (US) and to propose management guidelines for these lesions based on polyp size.
  
  
  METHODS
  The HIPAA-compliant study was approved by the institutional review board, and informed consent was waived. A database search for "polyp" in all US examinations of the GB between January 1, 1999, and December 31, 2001, at a single institution was performed. All subsequent US reports were reviewed to determine changes in GB polyp size. The electronic medical record was searched to obtain clinical and pathologic follow-up.
  
  
  RESULTS
  Three hundred forty-six patients (mean age, 51.6 years; range, 20-93 years) with GB polyps were included. There were 156 men (45%) and 190 women (55%). US follow-up (mean, 5.4 years; range, 2-11.5 years) was performed in 149 patients (43%). Polyp size was stable in 90 (60%) polyps, decreased in eight (5%), increased in one (1%), and resolved in 50 (34%). Forty-two patients (12%) underwent cholecystectomy, revealing 13 (31%) GBs with polypoid lesions, 24 (57%) with stones and no polyps, and five (12%) with neither a stone nor a polypoid lesion. Clinical follow-up (mean, 8 years; range, 5-10.4 years) was performed in 155 patients (45%). No patient had clinical evidence of GB-related disease. Overall, no cases of GB malignancy were identified in 346 patients. Mean polyp size was 5.0 mm (range, 1-18 mm). No neoplastic polyps were found at 1-6 mm, one neoplastic polyp was seen at 7-9 mm, and two neoplastic polyps were found at 10 mm or larger.
  
  
  CONCLUSIONS
  The risk of GB malignancy resulting from incidentally detected polyps is extremely low. Incidentally detected GB polyps measuring 6 mm or less may require no additional follow-up. Data are inconclusive regarding polyps 7 mm or greater, and further studies are warranted.
authors.affiliation: Department of Radiology, Beth Israel Deaconess Medical Center, 1 Deaconess Rd, CC/W 308, Boston, MA 02215, USA. corwinmichael@hotmail.com
authors.forename: Michael T
authors.initials: MT
authors.lastname: Corwin
authors.forename: Bettina
authors.initials: B
authors.lastname: Siewert
authors.forename: Robert G
authors.initials: RG
authors.lastname: Sheiman
authors.forename: Robert A
authors.initials: RA
authors.lastname: Kane
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002763:Cholecystectomy; D005260:Female; D005705:Gallbladder Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D005706:Gallbladder Neoplasms / Q000000981:diagnostic imaging; D006801:Humans; D033162:Incidental Findings; D008297:Male; D008875:Middle Aged; D011127:Polyps / Q000000981:diagnostic imaging* / Q000473:pathology; D014463:Ultrasonography