Gallbladder Polyps Rarely Grow Beyond 10mm - Close Surveillance is Unnecessary for Polyps Smaller than 10mm

Man Hon Tang
2018 Biomedical Journal of Scientific & Technical Research  
Introduction Gallbladder polyps (GBP) are elevated mucosal lesions projecting from the gallbladder wall into the gallbladder interior. The majority of GBP are diagnosed incidentally on imaging or histopathologically in cholecystectomy specimens. The reported prevalence of GBP ranges from 4-6% on ultrasonography [1-3] and 2-12% in cholecystectomy specimens [4, 5] . Most GBP are benign, the commonest being cholesterol polyps, accounting for 60-90% of polypoid gallbladder lesions. 4% of GBP are
more » ... s. 4% of GBP are adenomas-these are considered benign neoplasms, albeit with malignant potential. Gallbladder carcinoma has been postulated to arise from GBP through an adenoma-dysplasia-carcinoma sequence [6] . Given its dismal prognosis when diagnosed at advanced stages, detection and removal of early lesions offer a curative option for gallbladder cancer [7] . As such, many centres perform close surveillance for GBP, with some advocating 3-12 monthly scans [8-10]. However, recent studies have failed to demonstrate a clear progression of polyps to malignancy over time, and that if gallbladder carcinoma truly arises from polyps remains uncertain [9] [10] [11] . Gallahan & Conway suggested that the risk factors associated with developing gallbladder carcinoma are age >50 years, history of primary sclerosing cholangitis, concomitant gallstone disease, solitary gallbladder polyploid lesion, or polyp size >10mm [12] . We hypothesise that GBP do not require such frequent follow-ups. Unnecessary US add to the workload of our healthcare systems and burden patients with rising healthcare costs. Our study hopes to address this issue and suggest a safe interval for GBP surveillance. Abstract Introduction: Small gallbladder polyps (GBP) are usually asymptomatic and benign and are monitored with regular ultrasonography (US) surveillance. Although most centers repeat imaging within a year, there remains no consensus regarding appropriate scan intervals. Aims: To investigate the size stability of GBP and to review the need for close surveillance. Methods: All abdominal ultrasound scans performed in our hospital over 3-month period were reviewed. Patients with sonographic evidence of GBP and with subsequent surveillance were included. The demographics of patients, characteristics of polyps, and subsequent scans over the following five years were reviewed. Histological reports were obtained for patients who underwent cholecystectomy. Results: 96 patients were included in the study. Median age was 51 (range, 24-89) years with a male predominance (67.7%). Main indications for US were hepatitis follow-up (41.7%) and abdominal pain (20.8%). Most patients had multiple polyps (62.5%) and the median diameter of the largest polyp was 4 (range, 3-10) mm. An average of 4.5 scans were performed over five years following detection and most polyps remained stable in size, rarely growing beyond 10mm -only two patients had polyps beyond 10mm. No gallbladder carcinoma was detected during the follow-up period. Conclusion: GBP usually remain stable in size, seldom grow beyond 10mm, and are rarely malignant. Surveillance scans for polyps smaller than 10mm should not be performed at intervals less than a year. Nonetheless, it remains the diagnostic modality of choice for GBP as it offers good spatial resolution compared to CT and MRI. US can detect movement, which helps to differentiate polyps from stones. It is also cheaper, making it more suitable for long-term surveillance. In conclusion, our study shows that the majority of GBP are smaller than 10mm and they rarely grow significantly
doi:10.26717/bjstr.2018.09.001861 fatcat:xzjalairavd6noedrwjztpatby