Additional value of chest CT AI-based quantification of lung involvement in predicting death and ICU admission for COVID-19 patients.

Objectives: We evaluated the contribution of lung lesion quantification on chest CT using a clinical Artificial Intelligence (AI) software in predicting death and intensive care units (ICU) admission for COVID-19 patients. Methods: For 349 patients with positive COVID-19-PCR test that underwent a chest CT scan at admittance or during hospitalization, we applied the AI for lung and lung lesion segmentation to obtain lesion volume (LV), and LV/Total Lung Volume (TLV) ratio. ROC analysis was used to extract the best CT criterion in predicting death and ICU admission. Two prognostic models using multivariate logistic regressions were constructed to predict each outcome and were compared using AUC values. The first model ("Clinical") was based on patients' characteristics and clinical symptoms only. The second model ("Clinical+LV/TLV") included also the best CT criterion. Results: LV/TLV ratio demonstrated best performance for both outcomes; AUC of 67.8% (95% CI: 59.5 - 76.1) and 81.1% (95% CI: 75.7 - 86.5) respectively. Regarding death prediction, AUC values were 76.2% (95% CI: 69.9 - 82.6) and 79.9% (95%IC: 74.4 - 85.5) for the "Clinical" and the "Clinical+LV/TLV" models respectively, showing significant performance increase (+ 3.7%; p-value<0.001) when adding LV/TLV ratio. Similarly, for ICU admission prediction, AUC values were 74.9% (IC 95%: 69.2 - 80.6) and 84.8% (IC 95%: 80.4 - 89.2) respectively corresponding to significant performance increase (+ 10%: p-value<0.001). Conclusions: Using a clinical AI software to quantify the COVID-19 lung involvement on chest CT, combined with clinical variables, allows better prediction of death and ICU admission.

Prostate MRI versus PSA screening for prostate cancer detection (the MVP Study): a randomised clinical trial.

OBJECTIVES: Our objective was to compare prostate cancer detection rates between patients undergoing serum prostate-specific antigen (PSA) vs magnetic resonance imaging (MRI) for prostate cancer screening. DESIGN: Phase III open-label randomised controlled trial. SETTING: Single tertiary cancer centre in Toronto, Canada. PARTICIPANTS: Men 50 years of age and older with no history of PSA screening for ≥3 years, a negative digital rectal exam and no prior prostate biopsy. INTERVENTIONS: Patients were recommended to undergo a prostate biopsy if their PSA was ≥2.6 ng/mL (PSA arm) or if they had a PIRADS score of 4 or 5 (MRI arm). Patients underwent an end-of-study PSA in the MRI arm. PRIMARY AND SECONDARY OUTCOME MEASURES: Adenocarcinoma on prostate biopsy. Prostate biopsy rates and the presence of clinically significant prostate cancer were also compared. RESULTS: A total of 525 patients were randomised, with 266 in the PSA arm and 248 in the MRI arm. Due to challenges with accrual and study execution during the COVID-19 pandemic, the study was terminated early. In the PSA arm, 48 patients had an abnormal PSA and 28 (58%) agreed to undergo a prostate biopsy. In the MRI arm, 25 patients had a PIRADS score of 4 or 5 and 24 (96%) agreed to undergo a biopsy. The relative risk for MRI to recommend a prostate biopsy was 0.52 (95% CI 0.33 to 0.82, p=0.005), compared with PSA. The cancer detection rate for patients in the PSA arm was 29% (8 of 28) vs 63% (15 of 24, p=0.019) in the MRI arm, with a higher proportion of clinically significant cancer detected in the MRI arm (73% vs 50%). The relative risk for detecting cancer and clinically significant with MRI compared with PSA was 1.89 (95% CI 0.82 to 4.38, p=0.14) and 2.77 (95% CI 0.89 to 8.59, p=0.07), respectively. CONCLUSIONS: Prostate MRI as a stand-alone screening test reduced the rate of prostate biopsy. The number of clinically significant cancers detected was higher in the MRI arm, but this did not reach statistical significance. Due to early termination, the study was underpowered. More patients were willing to follow recommendations for prostate biopsy based on MRI results. TRIAL REGISTRATION NUMBER: NCT02799303.

Chest CT for rapid triage of patients in multiple emergency departments during COVID-19 epidemic: experience report from a large French university hospital.

OBJECTIVES: To assess the diagnostic performances of chest CT for triage of patients in multiple emergency departments during COVID-19 epidemic, in comparison with reverse transcription polymerase chain reaction (RT-PCR) test. METHOD: From March 3 to April 4, 2020, 694 consecutive patients from three emergency departments of a large university hospital, for which a hospitalization was planned whatever the reasons, i.e., COVID- or non-COVID-related, underwent a chest CT and one or several RT-PCR tests. Chest CTs were rated as "Surely COVID+," "Possible COVID+," or "COVID-" by experienced radiologists. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using the final RT-PCR test as standard of reference. The delays for CT reports and RT-PCR results were recorded and compared. RESULTS: Among the 694 patients, 287 were positive on the final RT-PCR exam. Concerning the 694 chest CT, 308 were rated as "Surely COVID+", 34 as "Possible COVID+," and 352 as "COVID-." When considering only the "Surely COVID+" CT as positive, accuracy, sensitivity, specificity, PPV, and NPV reached 88.9%, 90.2%, 88%, 84.1%, and 92.7%, respectively, with respect to final RT-PCR test. The mean delay for CT reports was three times shorter than for RT-PCR results (187 ± 148 min versus 573 ± 327 min, p < 0.0001). CONCLUSION: During COVID-19 epidemic phase, chest CT is a rapid and most probably an adequately reliable tool to refer patients requiring hospitalization to the COVID+ or COVID- hospital units, when response times for virological tests are too long. KEY POINTS: • In a large university hospital in Lyon, France, the accuracy, sensitivity, specificity, PPV, and NPV of chest CT for COVID-19 reached 88.9%, 90.2%, 88%, 84.1%, and 92.7%, respectively, using RT-PCR as standard of reference. • The mean delay for CT reports was three times shorter than for RT-PCR results (187 ± 148 min versus 573 ± 327 min, p < 0.0001). • Due to high accuracy of chest CT for COVID-19 and shorter time for CT reports than RT-PCR results, chest CT can be used to orient patients suspected to be positive towards the COVID+ unit to decrease congestion in the emergency departments.