RESUMEN
OBJECTIVE: To determine whether evaluating the mean apparent diffusion coefficient (ADC) together with capsular contact (CC) adds value in the prediction of microscopic extracapsular extension (ECE) of prostate cancer. MATERIALS AND METHODS: Between January 2012 and December 2016, 383 patients underwent multiparametric magnetic resonance imaging (mpMRI) of the prostate. A total of 67 patients were selected for inclusion. Two radiologists (observers 1 and 2), working independently, performed qualitative and quantitative analyses of ECE, macroscopic ECE, and microscopic ECE. A third radiologist assessed the correlation with the clinical data, and two experienced pathologists reviewed all histopathological findings. RESULTS: Among the 67 patients, mpMRI showed lesions that were confined to the capsule in 44 (66.7%), had microscopic ECE in 12 (17.9%), and had macroscopic ECE in 11 (16.4%). There were no significant differences, in terms of the diagnostic accuracy, as measured by determining the area under the curve (AUC), of CC on T2-weighted images (CCT2), CC on diffusion-weighted imaging (CCDWI), and the mean ADC for the prediction of microscopic ECE, between observer 1 (AUC of 0.728, 0.691, and 0.675, respectively) and observer 2 (AUC of 0.782, 0.821, and 0.799, respectively). Combining the mean ADC with the CCT2 or CCDWI did not improve the diagnostic accuracy for either observer. There was substantial interobserver agreement for the qualitative evaluation of ECE, as demonstrated by the kappa statistic, which was 0.77 (0.66-0.87). The diagnostic accuracy (AUC) of the qualitative assessment for predicting microscopic ECE was 0.745 for observer 1 and 0.804 for observer 2, and the difference was less than significant. In a multivariate analysis, none of clinical or imaging parameters were found to be associated with ECE. CONCLUSION: For the detection of microscopic ECE on mpMRI, CC appears to have good diagnostic accuracy, especially if the observer has considerable experience. Adding the mean ADC to the CCT2 or CCDWI does not seem to provide any significant improvement in that diagnostic accuracy.
OBJETIVO: Avaliar se o coeficiente de difusão aparente (apparent diffusion coefficient - ADC) médio tem valor incremental ao contato capsular (CC) na predição da extensão extracapsular (EEC) do câncer de próstata. MATERIAIS E MÉTODOS: De janeiro de 2012 a dezembro de 2016, 383 pacientes realizaram ressonância magnética multiparamétrica de próstata. Após os critérios de inclusão e exclusão, 67 pacientes foram selecionados para avaliação qualitativa e quantitativa, por dois radiologistas independentes, da EEC, EEC grosseira e EEC microscópica. Um terceiro observador coletou dados clínicos e dois patologistas experientes revisaram os achados histopatológicos. RESULTADOS: Dos 67 pacientes selecionados, 44 apresentaram lesões restritas à cápsula (66,7%), 12 com EEC microscópica (17,9%) e 11 com EEC grosseira (16,4%). Não houve diferença significativa entre a acurácia diagnóstica, medida pela área sob a curva, entre o CC na ponderação T2 (CCT2), CC-difusão e ADC para predição da EEC microscópica para ambos os observadores (0,728, 0,691 e 0,675, respectivamente, para o observador 1, e 0,782, 0,821 e 0,799, respectivamente, para o observador 2). A associação dos valores médios do ADC ao CCT2 e ao CC-difusão não promoveu melhora da acurácia diagnóstica. A concordância interobservador para a avaliação qualitativa da EEC mostrou coeficiente kappa de 0,77 (0,66-0,87), inferindo concordância substancial. A acurácia da avaliação qualitativa para EEC microscópica foi de 0,745 e 0,804 para os observadores 1 e 2, respectivamente, diferença não significativa. Na análise multivariada, nenhum parâmetro clínico ou de imagem foi associado a EEC. CONCLUSÃO: O CC mostrou boa acurácia diagnóstica para a detecção de EEC microscópica, especialmente para o observador mais experiente. A inclusão dos valores médios de ADC não melhorou a acurácia do CC para predição de EEC microscópica.
RESUMEN
Abstract Objective: To determine whether evaluating the mean apparent diffusion coefficient (ADC) together with capsular contact (CC) adds value in the prediction of microscopic extracapsular extension (ECE) of prostate cancer. Materials and Methods: Between January 2012 and December 2016, 383 patients underwent multiparametric magnetic resonance imaging (mpMRI) of the prostate. A total of 67 patients were selected for inclusion. Two radiologists (observers 1 and 2), working independently, performed qualitative and quantitative analyses of ECE, macroscopic ECE, and microscopic ECE. A third radiologist assessed the correlation with the clinical data, and two experienced pathologists reviewed all histopathological findings. Results: Among the 67 patients, mpMRI showed lesions that were confined to the capsule in 44 (66.7%), had microscopic ECE in 12 (17.9%), and had macroscopic ECE in 11 (16.4%). There were no significant differences, in terms of the diagnostic accuracy, as measured by determining the area under the curve (AUC), of CC on T2-weighted images (CCT2), CC on diffusion-weighted imaging (CCDWI), and the mean ADC for the prediction of microscopic ECE, between observer 1 (AUC of 0.728, 0.691, and 0.675, respectively) and observer 2 (AUC of 0.782, 0.821, and 0.799, respectively). Combining the mean ADC with the CCT2 or CCDWI did not improve the diagnostic accuracy for either observer. There was substantial interobserver agreement for the qualitative evaluation of ECE, as demonstrated by the kappa statistic, which was 0.77 (0.66-0.87). The diagnostic accuracy (AUC) of the qualitative assessment for predicting microscopic ECE was 0.745 for observer 1 and 0.804 for observer 2, and the difference was less than significant. In a multivariate analysis, none of clinical or imaging parameters were found to be associated with ECE. Conclusion: For the detection of microscopic ECE on mpMRI, CC appears to have good diagnostic accuracy, especially if the observer has considerable experience. Adding the mean ADC to the CCT2 or CCDWI does not seem to provide any significant improvement in that diagnostic accuracy.
Resumo Objetivo: Avaliar se o coeficiente de difusão aparente (apparent diffusion coefficient - ADC) médio tem valor incremental ao contato capsular (CC) na predição da extensão extracapsular (EEC) do câncer de próstata. Materiais e Métodos: De janeiro de 2012 a dezembro de 2016, 383 pacientes realizaram ressonância magnética multiparamétrica de próstata. Após os critérios de inclusão e exclusão, 67 pacientes foram selecionados para avaliação qualitativa e quantitativa, por dois radiologistas independentes, da EEC, EEC grosseira e EEC microscópica. Um terceiro observador coletou dados clínicos e dois patologistas experientes revisaram os achados histopatológicos. Resultados: Dos 67 pacientes selecionados, 44 apresentaram lesões restritas à cápsula (66,7%), 12 com EEC microscópica (17,9%) e 11 com EEC grosseira (16,4%). Não houve diferença significativa entre a acurácia diagnóstica, medida pela área sob a curva, entre o CC na ponderação T2 (CCT2), CC-difusão e ADC para predição da EEC microscópica para ambos os observadores (0,728, 0,691 e 0,675, respectivamente, para o observador 1, e 0,782, 0,821 e 0,799, respectivamente, para o observador 2). A associação dos valores médios do ADC ao CCT2 e ao CC-difusão não promoveu melhora da acurácia diagnóstica. A concordância interobservador para a avaliação qualitativa da EEC mostrou coeficiente kappa de 0,77 (0,66-0,87), inferindo concordância substancial. A acurácia da avaliação qualitativa para EEC microscópica foi de 0,745 e 0,804 para os observadores 1 e 2, respectivamente, diferença não significativa. Na análise multivariada, nenhum parâmetro clínico ou de imagem foi associado a EEC. Conclusão: O CC mostrou boa acurácia diagnóstica para a detecção de EEC microscópica, especialmente para o observador mais experiente. A inclusão dos valores médios de ADC não melhorou a acurácia do CC para predição de EEC microscópica.
RESUMEN
The differential diagnosis of renal tumors, particularly in adolescents, may be challenging. We describe an 11-year-old female with a primary intra-renal mass. Initial differential diagnoses included primitive neuroectodermal tumor (PNET), desmoplastic small round cell tumor (DSRCT), and Wilms Tumor (WT). Extensive pathologic and molecular analysis on initial and relapsed tumor samples confirmed WT. The EWS-WT1 and EWS-FLI1 rearrangements, distinctive of DSRCT and PNET were negative. The differential diagnosis on monophasic blastemal WT may be complex. Primary renal DSRCT and PNET have been rarely described. Nevertheless, molecular confirmation for these rare conditions may be necessary in selected cases.