A Hybrid End-to-End Approach Integrating Conditional Random Fields into CNNs for Prostate Cancer Detection on MRI

Prostate Cancer (PCa) is the most common oncological disease in Western men. Even though a growing effort has been carried out by the scientific community in recent years, accurate and reliable automated PCa detection methods on multiparametric Magnetic Resonance Imaging (mpMRI) are still a compelli...

Full description

Bibliographic Details
Main Authors: Paulo Lapa, Mauro Castelli, Ivo Gonçalves, Evis Sala, Leonardo Rundo
Format: Article
Language:English
Published: MDPI AG 2020-01-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/10/1/338
_version_ 1811270329753927680
author Paulo Lapa
Mauro Castelli
Ivo Gonçalves
Evis Sala
Leonardo Rundo
author_facet Paulo Lapa
Mauro Castelli
Ivo Gonçalves
Evis Sala
Leonardo Rundo
author_sort Paulo Lapa
collection DOAJ
description Prostate Cancer (PCa) is the most common oncological disease in Western men. Even though a growing effort has been carried out by the scientific community in recent years, accurate and reliable automated PCa detection methods on multiparametric Magnetic Resonance Imaging (mpMRI) are still a compelling issue. In this work, a Deep Neural Network architecture is developed for the task of classifying clinically significant PCa on non-contrast-enhanced MR images. In particular, we propose the use of Conditional Random Fields as a Recurrent Neural Network (CRF-RNN) to enhance the classification performance of XmasNet, a Convolutional Neural Network (CNN) architecture specifically tailored to the PROSTATEx17 Challenge. The devised approach builds a hybrid end-to-end trainable network, CRF-XmasNet, composed of an initial CNN component performing feature extraction and a CRF-based probabilistic graphical model component for structured prediction, without the need for two separate training procedures. Experimental results show the suitability of this method in terms of classification accuracy and training time, even though the high-variability of the observed results must be reduced before transferring the resulting architecture to a clinical environment. Interestingly, the use of CRFs as a separate postprocessing method achieves significantly lower performance with respect to the proposed hybrid end-to-end approach. The proposed hybrid end-to-end CRF-RNN approach yields excellent peak performance for all the CNN architectures taken into account, but it shows a high-variability, thus requiring future investigation on the integration of CRFs into a CNN.
first_indexed 2024-04-12T21:58:54Z
format Article
id doaj.art-e0a0df3e9c694043aa6b6ebfa2fc50b3
institution Directory Open Access Journal
issn 2076-3417
language English
last_indexed 2024-04-12T21:58:54Z
publishDate 2020-01-01
publisher MDPI AG
record_format Article
series Applied Sciences
spelling doaj.art-e0a0df3e9c694043aa6b6ebfa2fc50b32022-12-22T03:15:13ZengMDPI AGApplied Sciences2076-34172020-01-0110133810.3390/app10010338app10010338A Hybrid End-to-End Approach Integrating Conditional Random Fields into CNNs for Prostate Cancer Detection on MRIPaulo Lapa0Mauro Castelli1Ivo Gonçalves2Evis Sala3Leonardo Rundo4Nova Information Management School (NOVA IMS), Campus de Campolide, Universidade Nova de Lisboa, 1070-332 Lisboa, PortugalNova Information Management School (NOVA IMS), Campus de Campolide, Universidade Nova de Lisboa, 1070-332 Lisboa, PortugalINESC Coimbra, DEEC, University of Coimbra, Pólo 2, 3030-290 Coimbra, PortugalDepartment of Radiology, University of Cambridge, Cambridge CB2 0QQ, UKDepartment of Radiology, University of Cambridge, Cambridge CB2 0QQ, UKProstate Cancer (PCa) is the most common oncological disease in Western men. Even though a growing effort has been carried out by the scientific community in recent years, accurate and reliable automated PCa detection methods on multiparametric Magnetic Resonance Imaging (mpMRI) are still a compelling issue. In this work, a Deep Neural Network architecture is developed for the task of classifying clinically significant PCa on non-contrast-enhanced MR images. In particular, we propose the use of Conditional Random Fields as a Recurrent Neural Network (CRF-RNN) to enhance the classification performance of XmasNet, a Convolutional Neural Network (CNN) architecture specifically tailored to the PROSTATEx17 Challenge. The devised approach builds a hybrid end-to-end trainable network, CRF-XmasNet, composed of an initial CNN component performing feature extraction and a CRF-based probabilistic graphical model component for structured prediction, without the need for two separate training procedures. Experimental results show the suitability of this method in terms of classification accuracy and training time, even though the high-variability of the observed results must be reduced before transferring the resulting architecture to a clinical environment. Interestingly, the use of CRFs as a separate postprocessing method achieves significantly lower performance with respect to the proposed hybrid end-to-end approach. The proposed hybrid end-to-end CRF-RNN approach yields excellent peak performance for all the CNN architectures taken into account, but it shows a high-variability, thus requiring future investigation on the integration of CRFs into a CNN.https://www.mdpi.com/2076-3417/10/1/338prostate cancer detectionmagnetic resonance imagingconvolutional neural networksconditional random fieldsrecurrent neural networks
spellingShingle Paulo Lapa
Mauro Castelli
Ivo Gonçalves
Evis Sala
Leonardo Rundo
A Hybrid End-to-End Approach Integrating Conditional Random Fields into CNNs for Prostate Cancer Detection on MRI
Applied Sciences
prostate cancer detection
magnetic resonance imaging
convolutional neural networks
conditional random fields
recurrent neural networks
title A Hybrid End-to-End Approach Integrating Conditional Random Fields into CNNs for Prostate Cancer Detection on MRI
title_full A Hybrid End-to-End Approach Integrating Conditional Random Fields into CNNs for Prostate Cancer Detection on MRI
title_fullStr A Hybrid End-to-End Approach Integrating Conditional Random Fields into CNNs for Prostate Cancer Detection on MRI
title_full_unstemmed A Hybrid End-to-End Approach Integrating Conditional Random Fields into CNNs for Prostate Cancer Detection on MRI
title_short A Hybrid End-to-End Approach Integrating Conditional Random Fields into CNNs for Prostate Cancer Detection on MRI
title_sort hybrid end to end approach integrating conditional random fields into cnns for prostate cancer detection on mri
topic prostate cancer detection
magnetic resonance imaging
convolutional neural networks
conditional random fields
recurrent neural networks
url https://www.mdpi.com/2076-3417/10/1/338
work_keys_str_mv AT paulolapa ahybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri
AT maurocastelli ahybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri
AT ivogoncalves ahybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri
AT evissala ahybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri
AT leonardorundo ahybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri
AT paulolapa hybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri
AT maurocastelli hybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri
AT ivogoncalves hybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri
AT evissala hybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri
AT leonardorundo hybridendtoendapproachintegratingconditionalrandomfieldsintocnnsforprostatecancerdetectiononmri