Gallbladder cancer (GC) has been reported in 0.3-1.5% of cholecystectomies. Since the introduction of laparoscopic surgery, cholecystectomies have increased and occult GC may therefore be more frequent. Herein we analyze our own experience to determine whether there was an increase in GC. We also evaluate the risk factors for this outcome. Four patients with GC undiagnosed before surgery (four of 602 cases, or 0.66%) were submitted to laparoscopic cholecystectomy. The percentage in patients who underwent open surgery was 0.28% (two of 714 cases). Without reoperation, three patients died in the laparoscopic group and one is alive at 12 months. Trocar site metastasis was not observed. Although the percentage of GC (0.28% versus 0.66%) increased, the percentage is still in the referred average. Undiagnosed GC is on the increase. Examination of the gallbladder and a frozen section, if necessary, are recommended. Calcified gallbladders, age >70 years, a long history of stones, and a thickened gallbladder all represent significant risk factors.