Comparison of FDG-PET/CT and MR with diffusion-weighted imaging for assessing peritoneal carcinomatosis from gastrointestinal malignancy

• Published in: European radiology 2012-07, Vol.22 (7), p.1479-1487
• Main Authors: Soussan, Michael, Des Guetz, Gaëtan, Barrau, Vincent, Aflalo-Hazan, Vanessa, Pop, Gabriel, Mehanna, Ziad, Rust, Edmond, Aparicio, Thomas, Douard, Richard, Benamouzig, Robert, Wind, Philippe, Eder, Véronique
• Format: Article
• Language: English
• Subjects: Abdomen; Accuracy; Adult; Aged; Aged, 80 and over; Diagnostic Radiology; Diffusion Magnetic Resonance Imaging - methods; Early Diagnosis; Female; Fluorodeoxyglucose F18; Gastrointestinal Neoplasms - diagnosis; Humans; Imaging; Internal Medicine; Interventional Radiology; Magnetic Resonance Imaging - methods; Male; Medicine; Medicine & Public Health; Middle Aged; Multimodal Imaging - methods; Neuroradiology; Nuclear medicine; Oncology; Patients; Peritoneal Neoplasms - diagnosis; Positron-Emission Tomography; Radiology; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Subtraction Technique; Surgery; Tomography, X-Ray Computed; Tumors; Ultrasound
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s00330-012-2397-2

Objectives To assess the accuracy of FDG-PET/CT and MR with diffusion-weighted imaging (MR-DWI) for diagnosing peritoneal carcinomatosis (PC) from gastrointestinal malignancies. Methods Thirty consecutive patients referred for staging of gastrointestinal malignancy underwent FDG-PET/CT and MR-DWI in this retrospective study. Extent of PC was characterised by dividing the peritoneal cavity into three sites in each patient: right and left supramesocolic areas and inframesocolic level (total 90 sites). Presence of PC was confirmed either by surgery (18/30) or by follow-up (12/30). Results PC was confirmed in 19 patients (19/30). At a total of 90 sites, 27 showed proven PC. On a patient-based analysis, sensitivity, specificity, PPV, NPV and accuracy were respectively 84%, 73%, 84%, 73% and 80% for PET/CT and 84%, 82%, 89%, 75% and 83% for MR-DWI. On a site-based analysis, overall sensitivity and specificity of PET/CT (63%, 90%) and MR-DWI (74%, 97%) were not statistically different ( P  = 0.27). In the supramesocolic area, MR-DWI detected more sites involved than PET/CT (7/9 vs. 4/9). The sensitivities of PET and MR were lower for subcentimetre tumour implants (42%, 50%). Interobserver agreement was very good for PET/CT and good for MR-DWI. Conclusions FDG-PET/CT and MR-DWI showed similar high accuracy in diagnosing PC. Both techniques underestimated the real extent of PC because of decreased sensitivity for subcentimetre lesions. Key Points • FDG-PET/CT and MR-DWI showed similar high accuracy for diagnosing peritoneal carcinomatosis . • In the supramesocolic area, MR-DWI could be more sensitive than PET/CT . • Both techniques showed lower sensitivity for subcentimetre lesions . • Interobserver agreement was very good for PET/CT and good for MR-DWI .