Post treatment follow-up in carcinoma of the gall bladder: Efficacy of 18F-FDG-PET/CT for detection of suspected recurrence

1618 Objectives Recurrent carcinoma of the gall bladder has a poor prognosis. Conventional imaging (CI) and tumour markers have limited accuracy for detecting recurrence in these patients. The aim of this study was to evaluate the efficacy of 18F-FDG-PET/CT for follow-up of patients with suspected recurrence of carcinoma of the gall bladder. Methods A total of 22 patients were evaluated with 18F-FDG-PET/CT for suspected recurrence. All patients had undergone surgery with or without adjuvant therapy (chemotherapy, radiotherapy, or both) for histologically proven carcinoma of the gall bladder. Comparable CI (ultrasound or contrast-enhanced CT) was available for 14 patients. Final confirmation of recurrence was confirmed with clinical and/or imaging follow-up. Results Patients mean age was 53.9±9.78 years. 18F-FDG-PET/CT was positive for recurrence in 15 patients (68.1%) and negative in 7 (31.9%). Loco-regional disease was observed in 5 patients, metastatic disease was observed in 5, and 5 showed both loco-regional and metastatic disease. The sensitivity, specificity, positive and negative predictive values, and accuracy of 18F-FDG PET/CT were 93.5 %, 100%, 100%, 85.7%, and 95.4%, respectively. Compared to CI, 18F-FDG-PET/CT upstaged six patients, correctly characterized five patients suspected of recurrence as true negative, and concordant findings were noted in three patients. 4 of 15 recurrence positive patients detected with FDG died during follow-up period of 3.0 months and 11 are undergoing palliative radiotherapy/chemotherapy. Conclusions Accurate detection of recurrent carcinoma of the gall bladder after intended curative surgery, radiotherapy and/or chemotherapy is imperative to select the most appropriate therapeutic strategy. 18F-FDG-PET/CT appears to be a highly specific and sensitive modality for detecting recurrence in post-therapy patients.