OBJECTIVE: To evaluate the role of multidetector computed tomography in the preoperative investigation of tumor invasion depth and lymph node and metastatic involvement according to the TNM classification, in patients with gastric adenocarcinoma. MATERIALS AND METHODS: Fifty-four patients with biopsy-confirmed gastric cancer underwent preoperative staging with 64-channel multidetector computed tomography. Two independent radiologists analyzed the images and classified the findings. Sensitivity, specificity, accuracy and overall accuracy were calculated for each observer. The interobserver agreement was also evaluated. RESULTS: The accuracy in the classification of categories T ranged from 74% to 96% for observer 1 and from 80% to 92% for observer 2. The overall accuracy was 70% for both observers. The weighted kappa index was 0.75, consistent with a significant interobserver agreement. The accuracy in the classification of lymph node involvement (category N) ranged from 55% to 79% for observer 1 and from 73% to 82% for observer 2. The evaluation of metastatic involvement showed an overall accuracy of 89.6% for both observers. CONCLUSION: 64-channel multidetector computed tomography demonstrated clinically relevant accuracy in the preoperative staging of gastric adenocarcinoma as regards invasion depth (T category) and metastatic involvement (M category).

Keywords: Gastric cancer; Computed tomography; Staging.

We present a case of immunoglobulin G4 (IgG4)-related disease with pancreatic and extrapancreatic involvement, including the biliary and renal systems. Given the importance of imaging methods for the diagnosis of IgG4-related disease and its differentiation from pancreatic adenocarcinoma, we emphasize important abdominal computed tomography and magnetic resonance imaging findings related to this recently recognized systemic autoimmune disease.

Keywords: Pancreatitis; Autoimmune diseases; Pancreas; Computed tomography; Magnetic resonance imaging.

OBJECTIVE: To assess the performance of the Ovarian-Adnexal Reporting and Data System Magnetic Resonance Imaging (O-RADS MRI) score in the evaluation of adnexal masses and to provide technical notes about its current MRI parameters and concepts. MATERIALS AND METHODS: This was a prospective study of 226 patients with 287 adnexal masses (190 submitted to surgery or biopsy and 97 followed for at least one year). We calculated the sensitivity, specificity, positive predictive value, and negative predictive value for the O-RADS MRI score, using ≥ 4 as the cutoff for malignancy. We performed a technical analysis of the main updates to the score, announced in September 2020 by the American College of Radiology, in comparison with the original (2013) version. RESULTS: We found that an O-RADS MRI score of 4 or 5 was associated with malignancy of an adnexal mass, with a sensitivity of 91.11% (95% CI: 83.23–96.08), specificity of 94.92% (95% CI: 90.86–97.54), positive predictive value of 89.13% (95% CI: 81.71–93.77), negative predictive value of 95.90% (95% CI: 92.34–97.84), and overall accuracy of 93.73% (95% CI: 90.27–96.24). CONCLUSION: Our findings support the use of the O-RADS MRI score for evaluating adnexal masses, especially those considered indeterminate on ultrasound. The updates made recently to the O-RADS MRI score facilitate its interpretation and will allow its more widespread use, with no loss of diagnostic accuracy.

Keywords: Magnetic resonance imaging; Adnexal diseases/diagnostic imaging; Ovarian neoplasms/diagnostic imaging.