Benefits of ¹⁸F-FDG PET/CT for the preoperative characterisation or staging of disease in the ampullary and duodenal papillary.

Abstract

Diagnosing ampullary and duodenal papillary carcinomas (ADPCs) is challenging. In the present study, we investigated the application value of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) in the preoperative evaluation of these tumours. ¹⁸F-FDG PET/CT images of 58 patients with ADPC and 28 patients with benign disease were retrospectively analysed. Preoperative ¹⁸F-FDG PET/CT was compared to contrast-enhanced (CE) CT and magnetic resonance imaging (MRI) in terms of diagnostic efficacy, certainty, staging and impact on treatment decisions. ¹⁸F-FDG PET/CT showed a high sensitivity (93.1%) and a medium specificity (78.6%) for diagnosing ADPC. Compared to CE CT/MRI, ¹⁸F-FDG PET/CT had a higher diagnostic specificity (78.6 vs. 35.7%, p = 0.001) but a similar sensitivity (93.1 vs. 89.6%, p = 0.508). ¹⁸F-FDG PET/CT provided a much higher diagnostic certainty than CE CT/MRI (definite reports, 88.4 vs. 50.0%, χ² = 29.698, p < 0.001), especially for small tumours ≤ 1.5 cm, and found distant metastases in five patients. The ¹⁸F-FDG PET/CT findings affected the treatment plans of 11 patients and improved the confidence in the diagnoses of 28 patients. The present study demonstrated that ¹⁸F-FDG PET/CT can supplement CE CT/MRI to provide a more accurate diagnosis for ADPC, and thus, plays an important role in the decision-making process before complicated pancreaticoduodenectomy procedures. • It is a challenge for CT and MRI to diagnose ampullary carcinoma, especially at their early stage. • Our study demonstrated that the benefit of PET/CT was improving the diagnostic confidence for ampullary and duodenal papillary carcinomas. • ¹⁸F-FDG PET/CT can change the treatment decision for ampullary and duodenal papillary carcinomas.