Gallbladder polypoid lesions >15mm as indicators of T1b gallbladder cancer risk

Gallbladder polyps (GBPs) are found in 5-7% of the adult population. However, it is very important to differentiate between benign and malignant polyps to establish an appropriate treatment. The present study aimed to determine the relevance of the 10-mm size criterion and attempted to determine the cut-off diameter of T1b tumours, which requires additional surgical intervention.

Cases with GBPs were collected between January 2005 and January 2015. A total of 109 patients were enroled retrospectively. Information on age, sex, ultrasound findings, and blood laboratory tests was reviewed. The 10-mm criterion and T1b tumours were examined.

Sixty-nine females and 40 males were included in the study. Patient age was 45±10.7years (range 27-70years). The 10-mm cut-off sensitivity and specificity for predicting malignant polyps was 93.6% and 85.2%, respectively. Fifteen patients had malignant pathologic results, and one patient had GBP <10mm (intraepithelial, 8mm). Two patients had intraepithelial tumours of 12 and 13mm. Twelve malignant patients had T1b tumours with polyp sizes >15mm.

Gallbladder cancer may occur in polyps of <10mm. Larger size and older age were predictors of neoplastic GBPs. We suggest 15mm as the optimal cut-off point to predict T1b cancer.