Comparison of DWIBS/T2 image fusion and PET/CT for the diagnosis of cancer in the abdominal cavity.

Fusion images of diffusion-weighted whole-body imaging with background body signal suppression and T2-weighted image (DWIBS/T2) demonstrate a strong signal for malignancies, with a high contrast against the surrounding tissues, and enable anatomical analysis. In the present study, DWIBS/T2 was compared with 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for diagnosing cancer in the abdomen. Patient records, including imaging results of examination conducted between November 2012 and May 2014, were analyzed retrospectively. In total, 10 men (age, 73.6±9.6 years) and 8 women (age, 68.9±7.1 years) were enrolled into the current study. Of the enrolled patients, 2 were diagnosed with hepatocellular carcinoma, 1 with cholangiocellular carcinoma, 1 with liver metastasis, 2 with pancreatic ductal adenocarcinoma, 1 with renal cell carcinoma and 1 with malignant lymphoma. Benign lesions were also analyzed, including adenomyomatosis of the gallbladder (5 patients), intraductal papillary mucinous neoplasm (4 patients) and right adrenal adenoma (1 case). All the patients with cancer showed positive results on DWIBS/T2 images. However, only 7 out of 8 patients were positive with PET/CT. One patient with right renal cellular carcinoma was positive with DWIBS/T2, but negative with PET/CT. All the patients with benign lesions were negative with DWIBS/T2 and PET/CT. In conclusion, DWIBS/T2 was more sensitive in diagnosing cancer of organs in the abdominal cavity compared with PET/CT. Furthermore, negative results with DWIBS/T2 and PET/CT were useful for the diagnosis of benign lesions, such as adenomyomatosis of the gallbladder and intraductal papillary mucinous neoplasm.

Diagnostic accuracy of diffusion-weighted whole-body imaging with background body signal suppression/T2-weighted image fusion for the detection of abdominal solid cancer.

Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) images show significant contrast for cancer tissues against non-cancerous tissues. Fusion of a DWIBS and a T2-weighted image (DWIBS/T2) can be used to obtain functional, as well as anatomic, information. In the present study, the performance of DWIBS/T2 in the diagnosis of abdominal solid cancer was evaluated. The records of 14 patients were retrospectively analyzed [5 patients with hepatocellular carcinoma (HCC), 4 with metastatic liver cancer, 3 with pancreatic cancer, 1 with renal cellular carcinoma and 1 with malignant lymphoma of the para-aortic lymph node]. T1WI and T2WI scans did not detect pancreatic cancer in certain cases, whereas DWIs and DWIBS/T2 clearly demonstrated pancreatic cancer in all cases. In addition, metastatic liver cancer and HCC were successfully detected with abdominal US and CECT; however, US did not detect pancreatic cancer in 1 case, while CECT and DWIBS/T2 detected pancreatic cancer in all cases. In conclusion, the diagnostic performance of DWIBS/T2 was the same as that of abdominal US and CECT in detecting primary and metastatic liver cancer. DWIBS/T2 enabled the diagnosis of pancreatic cancer in cases where it was not detected with US, T1WI or T2WI.

Diffusion-weighted whole-body imaging with background body signal suppression/T2 image fusion for the diagnosis of colorectal polyp and cancer.

Diffusion-weighted whole-body imaging with background body signal suppression/T2 image fusion (DWIBS/T2) is useful for the diagnosis of cancer as it presents a clear contrast between cancerous and non-cancerous tissue. The present study investigated the limitations and advantages of DWIBS/T2 with regards to the diagnosis of colorectal polyp (CP) or cancer (CRC). The current study included patients diagnosed with CP or CRC following colonoscopy, who were subjected to DWIBS/T2 between July 2012 and March 2015. Patient records were analyzed retrospectively. Patients were subjected to DWIBS/T2 when they presented with abdominal cancers or inflammation. Colonoscopy was performed as part of screening, or if patients had suspected colon cancer or inflammatory bowel disease. A total of 8 male and 7 female patients were enrolled in the present study. All patients, with the exception of one who had been diagnosed with CRC following colonoscopy, had positive results and all patients diagnosed with CP following a colonoscopy, with the exception of one, had negative results on DWIBS/T2. Thus, CRC was detected by DWIBS/T2, while CP was not (P=0.0028). The diameter of CRC lesions was significantly larger than that of CP (P<0.0001) and that of lesions positive on DWIBS/T2 was significantly larger than that of negative lesions (P=0.0004). The depth of invasion tended to be greater for lesions positive on DWIBS/T2 compared with that of negative ones. This indicated that DWIBS/T2 may be suitable for the detection of CRC but not for detection of CP. The results of DWIBS/T2 may also be affected by lesion diameter and depth of invasion.

Diffusion-weighted whole-body imaging with background body signal suppression/T2-weighted image fusion of gastrointestinal cancers.

Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) yields positive results for cancer against the surrounding tissues. The combination of DWIBS and T2-weighted images (DWIBS/T2) in the diagnosis of gastrointestinal tract cancers was retrospectively analyzed in the present study. Patients were subjected to magnetic resonance imaging after cancer was diagnosed through specimens obtained via biopsy or endoscopic mucosal resection. Sixteen patients were assessed between July, 2012 and June, 2013 and the correlation between detection with DWIBS/T2 and T staging was analyzed. Regarding patients who underwent surgery, the correlation between detection with DWIBS/T2 and the diameter or depth of invasion was analyzed. All cancers that had advanced to >T2 stage were detectable by DWIBS/T2, whereas all cancers staged as T2) or invading beyond the muscularis propria.

Negative signals for adenomyomatosis of the gallbladder upon diffusion-weighted whole body imaging with background body signal suppression/T2-weighted image fusion analysis.

Differentiation between adenomyomatosis (ADM) and cancer of the gallbladder is necessary during diagnosis. Diffusion-weighted whole body imaging with background body signal suppression (DWIBS) images are able to indicate cancer and inflammation. The fusion of a DWIBS with a T2 weighted image (DWIBS/T2) facilitates both functional and anatomical investigations. In the present study, patient records and images from patients with surgically confirmed ADM from April 2012 to October 2014 were analyzed retrospectively. The enrolled patients, including 6 men (64.2±13.1 years) and 4 women (57.3±12.4 years) were subjected to DWIBS/T2 during routine clinical practice. The diagnosis of ADM was based on magnetic resonance cholangiopancreatography, transabdominal ultrasonography, and endoscopic ultrasonography; ADM was diagnosed definitively when cystic lesions were observed, indicating the Rokitansky-Aschoff sinus. A single patient was indicated to be positive by DWIBS/T2 imaging. The Rokitansky-Aschoff sinus revealed a relatively high signal intensity; however, it was not as strong as that of the spleen. The signal intensity was also high on an apparent diffusion coefficient map, suggesting T2 shine-through. The thickened wall displayed low signal intensity. The aforementioned results indicate that ADM may be negative upon DWIBS/T2 imaging; one false positive case was determined to be ADM, accompanied by chronic cholecystitis. The majority of patients with ADM displayed negative findings upon DWIBS/T2 imaging, and chronic cholecystitis may cause false positives.