Incidental gall bladder cancer in the laparoscopic treatment and magnetic resonance imaging era: A single institution experience.

Background: Incidental gall bladder cancer (IGBC) is often discovered unexpectedly in patients after cholecystectomy. Currently, magnetic resonance imaging (MRI) has been widely applied in the pre-operative diagnosis of gall bladder diseases as laparoscopic cholecystectomy developed into the preferred method.

Aims and objectives: This study aimed to evaluate the pre-operative MRI application and laparoscopic management in the IGBCs.

Materials and methods: Between January 2011 and January 2020, a total of 7917 patients with gall bladder diseases treated by laparoscopy were enrolled in this study.

Results: Amongst 49 patients diagnosed with IGBCs, the incidence of IGBCs in polypoid lesions, biliary pancreatitis, cholecystitis, cholecystocholedocholithiasis and gall bladder stones was 0.42%, 1.19%, 0.62%, 1.20% and 0.49%, respectively. MRI evaluation showed more remarkable pre-operative imaging as compared to ultrasonographic evaluation (40.8 vs. 26.5, P < 0.05). Furthermore, 14 patients were diagnosed with gall bladder cancer through intraoperative histological examination and 11 received laparoscopic extensive resection after cholecystectomy. MRI findings with diffuse thickening of the gall bladder detected IGBCs with 6.1% sensitivity, 96.02 specificity, 0.95% positive predictive values and 99.4% negative predictive values; diffuse thickening of the gall bladder with suspicion of malignancy detected IGBCs with 12.2% sensitivity, 99.1% specificity, 7.6% positive predictive values and 99.5% negative predictive values; focal thickening of the gall bladder detected IGBCs with 16% sensitivity, 99.8% specificity, 32% positive predictive values and 99.5% negative predictive values; moreover, suspicious lesion detected IGBCs with 6.1% sensitivity, 99.6% specificity, 8.8% positive predictive values and 99.4% negative predictive values.

Conclusions: Patients with biliary pancreatitis and cholecystocholedocholithiasis have a higher incidence of IGBC. MRI evaluation could provide more accurate information for the IGBCs, which should be recommended for patients accepting cholecystectomy. MRI findings exhibited an unsatisfactory sensitivity when detecting IGBCs, but they represented high specificity. Pre-operative MRI evaluation and intraoperative histological examination may help some IGBCs to achieve one-stage laparoscopic extensive resection.