Stephen E. McRae

BACKGROUND: The objective of this study was to determine the prognostic variables that influence response and survival in patients with metastatic neuroendocrine tumors who are treated with hepatic arterial embolization (HAE) or chemoembolization (HACE). METHODS: Patients with metastatic neuroendocrine tumors who underwent HAE or HACE were included in this retrospective study. Follow-up imaging studies were compared with baseline imaging to determine the radiologic response. Progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan-Meier method. Univariate and multivariate analyses were performed to assess the prognostic variables that affected response and survival. RESULTS: The study included 69 patients with carcinoid tumors and 54 patients with pancreatic islet cell carcinomas. Patients who had carcinoid tumors had a higher response rate (66.7% vs. 35.2%; P = 0.0001) and had longer PFS (22.7 mos vs. 16.1 mos; P = 0.046) and OS (33.8 mos vs. 23.2 mos; P = 0.012) compared with patients who had islet cell carcinomas. For patients with carcinoid tumors, multivariate analysis identified male gender as the only independent risk factor for poor survival (P = 0.05). Octreotide was predictive marginally for PFS (P = 0.06). Patients who were treated with HAE had a higher response rate than patients who were treated with HACE (P = 0.004). For patients with islet cell carcinoma, an intact primary tumor, > or = 75% liver involvement, and extrahepatic metastases were associated with reduced OS in the univariate analysis; the presence of bone metastases was the only risk factor (P = 0.031) in the multivariate analysis. Patients who were treated with HACE had a prolonged OS (31.5 mos vs. 18.2 mos) and improved response (50% vs. 25%) compared with patients who were treated with HAE, although the differences did not reach statistical significance. CONCLUSIONS: Patients with carcinoid tumors had better outcomes than patients with islet cell carcinomas. The addition of intraarterial chemotherapy to HAE did not improve the outcome of patients with carcinoid tumors, but it seemed to benefit patients with islet cell carcinomas. In patients who had carcinoid tumors, male gender predicted a poor outcome, and a trend toward prolonged PFS was observed in patients who received concomitant octreotide. An intact primary tumor, extensive liver disease, and bone metastases were associated with reduced survival in patients with islet cell carcinomas.

Background Prostate MRI is used widely in clinical care for guiding tissue sampling, active surveillance, and staging. The Prostate Imaging Reporting and Data System (PI-RADS) helps provide a standardized probabilistic approach for identifying clinically significant prostate cancer. Despite widespread use, the variability in performance of prostate MRI across practices remains unknown. Purpose To estimate the positive predictive value (PPV) of PI-RADS for the detection of high-grade prostate cancer across imaging centers. Materials and Methods This retrospective cross-sectional study was compliant with the HIPAA. Twenty-six centers with members in the Society of Abdominal Radiology Prostate Cancer Disease-focused Panel submitted data from men with suspected or biopsy-proven untreated prostate cancer. MRI scans were obtained between January 2015 and April 2018. This was followed with targeted biopsy. Only men with at least one MRI lesion assigned a PI-RADS score of 2–5 were included. Outcome was prostate cancer with Gleason score (GS) greater than or equal to 3+4 (International Society of Urological Pathology grade group ≥2). A mixed-model logistic regression with institution and individuals as random effects was used to estimate overall PPVs. The variability of observed PPV of PI-RADS across imaging centers was described by using the median and interquartile range. Results The authors evaluated 3449 men (mean age, 65 years ± 8 [standard deviation]) with 5082 lesions. Biopsy results showed 1698 cancers with GS greater than or equal to 3+4 (International Society of Urological Pathology grade group ≥2) in 2082 men. Across all centers, the estimated PPV was 35% (95% confidence interval [CI]: 27%, 43%) for a PI-RADS score greater than or equal to 3 and 49% (95% CI: 40%, 58%) for a PI-RADS score greater than or equal to 4. The interquartile ranges of PPV at these same PI-RADS score thresholds were 27%–44% and 27%–48%, respectively. Conclusion The positive predictive value of the Prostate Imaging and Reporting Data System was low and varied widely across centers. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Milot in this issue.