Role of F18-FDG PET-CT in detecting recurrent disease in patients of gall bladder cancer with clinical suspicion of recurrence

Objectives The role of F18-FDG PET-CT in gall bladder cancer is not well defined in literature. The present study was aimed to determine the efficacy of PET-CT in patients with gall bladder cancer suspected of having recurrence.

Methods This retrospective analysis includes 40 patients (Male=13, Female=27; Mean age-54.3years, Range-33-82 years) of gall bladder cancer suspected of having recurrent disease who underwent a total of 50 PET-CT scans. The interpretation of PET-CT images was based on FDG uptake (present or absent), pattern of uptake, invasion to surrounding structure and metastasis. Results of PET-CT were compared with histopathology and/or clinical follow up of the patients. Sensitivity, specificity, PPV, NPV and accuracy of PET-CT were calculated.

Results Out of 50 PET-CT scans, 33 (66%) were positive and 17 (34%) were negative for recurrent disease. Of 33 positive PET-CT scans, 31 were true positive while 2 were false positive scans. Among 17 negative PET-CT scans, 15 were true negative and 2 were false negative scans. PET-CT showed a sensitivity of 94% and specificity of 88% in detecting tumor recurrence in these patients. The PPV, NPV and accuracy were 94%, 88%, and 92%, respectively. Liver with loco-regional metastases were seen in 18 scans (36%) while distant metastases were seen in 23 scans (46%).

Conclusions F18-FDG PET-CT showed high sensitivity, specificity and accuracy in detecting recurrence in patients with gall bladder cancer. There was a high propensity for local recurrence and distant metastases in these patients.