Abstract
1409
Objectives To establish the value of PET for the detection of suspected recurrent pancreatic adenocarcinoma previously treated compared to ceCT and CA19.9.
Methods Thirty-two patients operated for pancreatic adenocarcinoma with suspected local and/or distant disease recurrence were enrolled. Both PET and ceCT were done and compared. After analysis of PET, SUVmax was defined by placing ROI on the site of pancreatic pathological uptake. Additionally, all patients underwent ceCT. Positive findings at PET or ceCT were compared to CA19.9 and follow-up.
Results Of 32 patients enrolled, 10 (31.2%) showed negative both PET and ceCT. Of 22 positive cases (68.7%) PET overall showed 26 areas of focal uptake divided as follow: 3 pancreatic bed, 9 hepatic, 2 pulmonary, 9 lymph nodal (7 subdiaphragmatic, 2 supradiaphragmatic), and 3 peritoneal. On the other hand ceCT showed overall 50 areas divided as follow: 1 pancreatic bed, 6 bone, 19 hepatic, 5 pulmonary, 17 lymph nodal (12 subdiaphragmatic, 5 supradiaphragmatic), 1 peritoneal and 1 of adrenal gland. From the comparison between CA19.9 and SUVmax, in 12 out of 22 positive PET patients we observed a significant correlation (p<0.1) between increase of CA19.9 and SUVmax. Ten cases with negative PET showed a lowest CA19.9 level.
Conclusions PET detects local and peritoneal recurrences, whereas ceCT is more sensitive for the detection of hepatic, bone, lymph node and lung metastases. Although less reliable in the identification of lymph nodes, PET is able to highlight mediastinal lymph nodes. Furthermore, PET is not advantageous for the detection of non locoregional and extra-abdominal recurrences. We show a significant direct correlation between growth of CA19.9 and SUVmax. Negative PET and CT with positive CA19.9 is probably linked to the small size of recurrent disease.