Multiple mathematical models of diffusion-weighted magnetic resonance imaging combined with prognostic factors for assessing the response to neoadjuvant chemotherapy and radiation therapy in locally advanced rectal cancer.
Eur J Radiol
; 110: 249-255, 2019 Jan.
Article
em En
| MEDLINE
| ID: mdl-30599868
ABSTRACT
PURPOSE:
To investigate whether the apparent diffusion coefficient (ADC), intravoxel incoherent motion (IVIM), and stretched exponential model (SEM) based on histogram analyses derived from the whole-tumor volume combined with prognostic factors can be used to assess the response to chemotherapy and radiation therapy (CRT) in locally advanced rectal cancer (LARC). MATERIALS ANDMETHODS:
This study included 60 patients with LARC who underwent diffusion-weighted imaging with 9b values (0-1000s/mm2) before CRT. Histograms derived from the whole-tumor volume were used to obtain the ADC, IVIM (Dslow, Dfast, and f), and SEM parameters (distributed diffusion coefficient (DDC) and α). The histogram metrics and prognostic factors before CRT were compared between pathological complete response (pCR) and non-pCR patients. The receiver operating characteristic (ROC) and the area under the ROC curve (AUC) were generated to analyze the histogram metrics and prognostic factors.RESULTS:
A significant difference was only found in the tumor volume between the pCR and non-pCR groups (p = 0.033, AUC = 0.740). The ADC mean, DDC median, and most of the histogram metrics were significantly lower in the pCR group than the non-pCR group (p = 0.000-0.025), and AUC was highest for the ADC mean (0.890). Only the Dslow median differed significantly between the two groups (p = 0.023, AUC = 0.721). However, the Dfast, f, and α histogram metrics did not differ significantly between the pCR and non-pCR groups. The AUC for the ADC mean combined with the tumor volume was 0.908, with a sensitivity of 100% and specificity of 81%. The inter-observer agreements were good or excellent for the ADC and SEM histogram parameters but generally fair for IVIM.CONCLUSION:
The whole-tumor ADC mean combined with the tumor volume was highly accurate for predicting pCR. The IVIM models were inferior to ADC and SEM at predicting pCR.Palavras-chave
Texto completo:
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Bases de dados:
MEDLINE
Assunto principal:
Neoplasias Retais
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Terapia Neoadjuvante
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Imagem de Difusão por Ressonância Magnética
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Modelos Teóricos
Tipo de estudo:
Diagnostic_studies
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Prognostic_studies
Limite:
Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Eur J Radiol
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
China