Objective value on Apparent diffusion coefficient (ADC) map to categorize the intensity of diffusion-weighted imaging (DWI) restriction for prostate cancer detection on multiparametric prostate MRI

ABSTRACT Purpose: To identify objective and subjective criteria on multiparametric prostate MRI that can be helpful for prostate cancer detection. Materials and Methods: Retrospective study, IRB approved, including 122 patients who had suspicious lesion on MRI and who underwent prostate biopsy with ultrasonography (US)/MRI imaging fusion. There were 60 patients with positive biopsies and 62 with negative biopsies. MRI of these patients were randomized and evaluated independently by two blinded radiologists. The following variables were analyzed in each lesion: morphology, contours, T2 signal, diffusion restriction (subjective impression and objective values), hyper-enhancement, contact with transition zone or prostatic contour, prostatic contour retraction, Likert and PIRADS classification. Results: Apparent diffusion coefficient (ADC) value was the best predictor of positivity for prostate cancer, with mean value of 1.08 (SD 0.20) and 1.09 mm2/sec (SD 0.24) on negative biopsies and 0.81 (SD 0.22) and 0.84 mm2/sec (SD 0.22) on positive biopsies for readers 1 and 2, respectively (p < 0.001 in both analysis). For the others categorical variables evaluated the best AUC for reader 1 was subjective intensity of diffusion restriction (AUC of 0.74) and for reader 2 was hyper-enhancement (AUC of 0.65), all inferior comparing to the value of ADC map. Interobserver agreement ranged from 0.13 to 0.75, poor in most measurements, and good or excellent (kappa > 0.6) only in lesion size and ADC values. Conclusions: Diffusion restriction with lower ADC-values is the best parameter to predict cancer on MRI prior to biopsy. Efforts to establish an ADC cutoff value would improve cancer detection, especially for less experience reader.

Objective value on Apparent diffusion coefficient (ADC) map to categorize the intensity of diffusion-weighted imaging (DWI) restriction for prostate cancer detection on multiparametric prostate MRI.

PURPOSE: To identify objective and subjective criteria on multiparametric prostate MRI that can be helpful for prostate cancer detection. MATERIALS AND METHODS: Retrospective study, IRB approved, including 122 patients who had suspicious lesion on MRI and who underwent prostate biopsy with ultrasonography (US)/MRI imaging fusion. There were 60 patients with positive biopsies and 62 with negative biopsies. MRI of these patients were randomized and evaluated independently by two blinded radiologists. The following variables were analyzed in each lesion: morphology, contours, T2 signal, diffusion restriction (subjective impression and objective values), hyper-enhancement, contact with transition zone or prostatic contour, prostatic contour retraction, Likert and PIRADS classification. RESULTS: Apparent diffusion coefficient (ADC) value was the best predictor of positivity for prostate cancer, with mean value of 1.08 (SD 0.20) and 1.09 mm2/sec (SD 0.24) on negative biopsies and 0.81 (SD 0.22) and 0.84 mm2/sec (SD 0.22) on positive biopsies for readers 1 and 2, respectively (p < 0.001 in both analysis). For the others categorical variables evaluated the best AUC for reader 1 was subjective intensity of diffusion restriction (AUC of 0.74) and for reader 2 was hyper-enhancement (AUC of 0.65), all inferior comparing to the value of ADC map. Interobserver agreement ranged from 0.13 to 0.75, poor in most measurements, and good or excellent (kappa > 0.6) only in lesion size and ADC values. CONCLUSIONS: Diffusion restriction with lower ADC-values is the best parameter to predict cancer on MRI prior to biopsy. Efforts to establish an ADC cutoff value would improve cancer detection, especially for less experience reader.

Aterosclerose: aneurisma de aorta versus coronariopatia. Estudo de40 casos com necropsia / Atherosclerosis: aortic aneurysm versus coronary artery disease. A study of 40 autopsy cases

JUSTIFICATIVAS E OBJETIVOS: A associação entre aneurisma de aorta por aterosclerose e a coronariopatia por aterosclerosetem abordagem relevante na literatura devido à importância epidemiológica e clínica; altas taxas de morbimortalidade e a influência dos fatores de risco para aterosclerose. O objetivo foi verificar a presença de aterosclerose coronariana em pacientes com aneurisma de aorta, a correlação entre os aneurismas deaorta e a extensão e grau de estenose coronariana, a localização mais frequente dos aneurismas e sua relação com a aterosclerose coronariana. MÉTODOS: Estudo retrospectivo de 4872necropsias realizadas em 23 anos, nos quais foram separados40 casos de aneurisma de aorta e nestes avaliados a extensão da coronariopatia (uniarterial, biarterial ou triarterial) e o grau de estenose: grau 1 ≤ 50%; grau 2 entre 50 a 70% e grau 3 >70%. Foram considerados aneurismas dilatações >50% do diâmetro normal da aorta e diferenciados segundo à localização: torácica, toracoabdominal e abdominal. Os casos foram selecionados independentemente do sexo e idade e a análise estatística baseada na distribuição percentual dos dados. RESULTADOS: Dos 40 casos de aneurisma de aorta, 30 (75%) eram coronariopatas,sendo 6 uniarteriais (20%), 5 biarteriais (16,6%) e 19 triarteriais (63,3%), com estenose grau 1 em 5 casos (16,6%), 10 com grau 2 (33,33%) e 15 com grau 3 (50%). O grau 3 de estenose e o comprometimento triarterial foi o mais freqüente quando correlacionados, principalmente nos aneurismas de aorta abdominal, localização mais verificada neste estudo, 27 casos (67%). CONCLUSÃO: Como a maioria dos aneurismas de aorta abdominal são assintomáticos, esse trabalho permite inferir que se deve investigar, rotineiramente, o abdome dos pacientes com aterosclerose grave nas coronárias e vice versa...

BACKGROUND AND OBJECTIVES: The association between atherosclerotic aortic aneurysm and coronary atherosclerosis is relevant due to its epidemiological and clinical importance, high morbidity rates and atherosclerosis influence risk factors.The goal was to verify the presence of coronary atherosclerosisin aortic an eurysm patients, the aortic aneurysm/coronarystenosis correlation, the most frequent aneurysm locations and their relation with coronary atherosclerosis. METHODS: Retrospective study done through 4872 autopsy reports in 23 years, of which 40 cases of aortic aneurysm were evaluated for coronary artery disease extent (single-vessel, double or triple vessels) and stenosis degree: degree 1: ≤50%, degree 2: 50%-70% and degree 3: >70%. The considered aneurysms had dilations>50% of the aorta?s normal diameter and were differentiated according to location: thoracic aortic, abdominal and thoracoabdominal. The cases were selected regardless of genderand age, and statistical analysis was performed based on the percentage of data distribution. RESULTS: Of the 40 cases ofaortic aneurysm, 30 (75%) had coronary artery disease, 6 (20%)single-vessel disease, 5 (16,6%) two-vessel disease, 19 (63.3%) three-vessel disease, degree-1 stenosis in 5 (16.6%) cases, 10 (33.33%) degree-2 cases and 15 (50%) degree-3 cases. Degree3 stenosis and triple vessel involvement was more frequent when correlated, especially in abdominal aortic aneurysms, also the most established location in this study, 27 cases (67%). CONCLUSION: As most abdominal aortic aneurysms are asymptomatic, this study allows us to infer that the abdomen of patients with severe atherosclerosis in the coronary arteries mustbe routinely investigated and vice versa...