1. Evaluate the usefulness of 18F-FDG PET/CT in identification of relapse of cholangiocarcinoma after surgery.
2. Evaluate if there is a correlation between pre-therapy SUVmax and the response to therapy.
3. Evaluate the response to chemotherapy by EORTC PET/CT criteria.
From August 2003 to March 2014,19 pts with cholangiocarcinoma(CCC),previously treated with surgery and adjuvant chemotherapy,were studied with 18F-FDG PET/CT for suspicious of relapse before and after chemotherapy(CHT).
13 men,6 women,were included in the current study.6 pts with ICC (intrahepatic cholangiocarcinoma),13 pts with ECC(extrahepatic cholangiocarcinoma:8 distal duct bile cancer,3 pts with Gall Bladder Cancer and 2 with Ampulla of Vater Carcinoma).
18F-FDG PET/CT during follow-up after radical surgery was performed for confirming a suspicious of relapse on ceCT or MRI.All patients with metastatic disease underwent systemic CHT and a second PET/CT was performed to evaluated the therapy response.Follow-up information was obtained for a minimum 12-24 months period subsequent to the date of PET/CT scan.
As the main criteria to reach the final diagnosis we used visual interpretation.We considered as malignant any uptake higher than background excluding any physiological uptake/obvious inflammatory findings.The maximum Standardized Uptake Values was measured for all lesions.PET/CT true positive findings lasting more than 12 months and/or repeated.PET/CT and ceCT revealing the appearance of further metastatic lesions or the disappearance of metastatic lesions following therapies.
PET/CT assessment after chemotherapy has been performed 1-to 6-months. Response evaluation with PET/CT was performed according to EORTC criteria and classified patients into 4 response categories: complete metabolic response (CR),partial metabolic response (PR),stable metabolic disease (SD) and progressive disease (PD).
The role of 18F-FDG PET/CT:
– in detecting T(intrahepatic disease):12/19 pts resulted positive on PET/CT and 7/19 pts resulted negative on PET/CT.All PET positive lesions were confirmed to be positive on follow up.No false negative (FN) findings after final diagnosis were found.
-in detecting N(lymph node metastases):8/19 pts resulted positive on PET/CT and 9/19 pts resulted negative on PET/CT.Two FN findings were detected in hepato-duodenal ligament in patients with ECC.
-in detecting M(distant metastasis):4/19 pts resulted positive on PET/CT and 13/19 pts resulted negative on PET/CT.Two FN findings were detected in lungs.
The pre-therapy SUVmax value wasn’t found to correlate with therapy response (p<0.14).As a consequence of small number of patients and limited follow up it’s not possible correlate SUVmax with overall survival.
After therapy CR was obtained in 4/19 pts;PR 5/19 pts,PD in 7/19 pts,SD in 3/19 pts.
This method has a better accuracy in patient with ICC than in patient with ECC.18F-FDG PET/CT was optimal in the assessment of T status,sub-optimal in the evaluation of N and M status. We haven’t found any correlation between pre-therapy SUVmax and therapy response.