Two-Stage Convolutional Neural Network for Breast Cancer Histology Image Classification

This paper explores the problem of breast tissue classification of microscopy images. Based on the predominant cancer type the goal is to classify images into four categories of normal, benign, in situ carcinoma, and invasive carcinoma. Given a suitable training dataset, we utilize deep learning techniques to address the classification problem. Due to the large size of each image in the training dataset, we propose a patch-based technique which consists of two consecutive convolutional neural networks. The first "patch-wise" network acts as an auto-encoder that extracts the most salient features of image patches while the second "image-wise" network performs classification of the whole image. The first network is pre-trained and aimed at extracting local information while the second network obtains global information of an input image. We trained the networks using the ICIAR 2018 grand challenge on BreAst Cancer Histology (BACH) dataset. The proposed method yields 95 % accuracy on the validation set compared to previously reported 77 % accuracy rates in the literature. Our code is publicly available at https://github.com/ImagingLab/ICIAR2018Comment: 10 pages, 5 figures, ICIAR 2018 conferenc

Nuclei segmentation for computer-aided diagnosis of breast cancer

Breast cancer is the most common cancer among women. The effectiveness of treatment depends on early detection of the disease. Computer-aided diagnosis plays an increasingly important role in this field. Particularly, digital pathology has recently become of interest to a growing number of scientists. This work reports on advances in computer-aided breast cancer diagnosis based on the analysis of cytological images of fine needle biopsies. The task at hand is to classify those as either benign or malignant. We propose a robust segmentation procedure giving satisfactory nuclei separation even when they are densely clustered in the image. Firstly, we determine centers of the nuclei using conditional erosion. The erosion is performed on a binary mask obtained with the use of adaptive thresholding in grayscale and clustering in a color space. Then, we use the multi-label fast marching algorithm initialized with the centers to obtain the final segmentation. A set of 84 features extracted from the nuclei is used in the classification by three different classifiers. The approach was tested on 450 microscopic images of fine needle biopsies obtained from patients of the Regional Hospital in Zielona Góra, Poland. The classification accuracy presented in this paper reaches 100%, which shows that a medical decision support system based on our method would provide accurate diagnostic information

Feature selection for breast cancer malignancy classification problem

The paper provides a preview of some work in progress on the computer system to support breast cancer diagnosis. Diagnosis approach is based on microscope images of the FNB (Fine Needle Biopsy) and assumes distinguishing malignant from benign cases. Studies conducted focus on two different problems, the first concern the extraction of morphometric parameters of nuclei present in cytological images and the other concentrate on breast cancer nature classification using selected features. Studies in both areas are conducted in parallel. This work is devoted to the problem of feature selection from the set of determined features in order to maximize the accuracy of classification. Morphometric features are derived directly from a digital scans of breast fine needle biopsy slides and are computed for segmented nuclei. The quality of feature space is measured with four different classification methods. In order to illustrate the effectiveness of the approach, the automatic system of malignancy classification was applied on a set of medical images with promising results

Hybrydowa metoda segmentacji obrazów cytologicznych oparta o konkurencyjne sieci neuronowe i adaptacyjne progowanie

The paper provides a preview of research on the computer system to support breast cancer diagnosis. The approach is based on analysis of microscope images of fine needle biopsy material. The article is devoted mainly to the segmentation problem. Hybrid segmentation algorithm based on competitive learning neural network and adaptive thresholding is presented. The system was tested on a set of real case medical images obtained from patients of the hospital in Zielona Góra with promising results.Niniejszy artukuł przedstawia wyniki prac badawczych prowadzonych nad komputerowym systemem wspierającym diagnostykę raka piersi. Zaprezentowane podejscie oparte jest na analizie mikroskopowych obrazów materiału pozyskanego metodą biopsji cienkoigłowej bez aspiracji. Zadaniem systemu jest określenie czy badany przypadek jest zmianą łagodną czy złośliwą. Badania skupione są na dwóch głównych problemach. Pierwszym z nich jest segmentacja obrazów cytologicznych oraz ekstrakcja cech morfometrycznych jąder komórkowych występujących na rozmazach. Drugim problemem jest klasyfikacja raka sutka oraz odpowiedni dobór cech najlepiej opisujących daną klasę. W artykule autorzy położyli główny nacisk na opisie sposobu segmentacji obrazów. Poprawność procesu segmentacji w dużym stopniu decyduje o możliwości wykonania skutecznych pomiarów cech morfometrycznych jąder komórkowych i w konsekwencji dokonania właściwej diagnozy. W artykule przedstawiono hybrydowy algorytm segmentacji oparty o konkurencyjne sieci neuronowe i adaptacyjne progowanie. Jest to metoda alternatywna do zaprezentowanej wcześniej metody bazującej na rozmytym algorytmie c-średnich. Porównanie wyników obydwu metod zamieszczono w artykule. Automatyczny system wspierający diagnostykę raka piersi przetestowano na prawdziwych obrazach medycznych pacjentów regionalnego szpitala w Zielonej Górze. W przeprowadzonych eksperymetach uzyskano obiecujące wyniki

GLCM and GLRLM based texture features for computer-aided breast cancer diagnosis

This paper presents 15 texture features based on GLCM (Gray-Level Co-occurrence Matrix) and GLRLM (Gray-Level Run-Length Matrix) to be used in an automatic computer system for breast cancer diagnosis. The task of the system is to distinguish benign from malignant tumors based on analysis of fine needle biopsy microscopic images. The features were tested whether they provide important diagnostic information. For this purpose the authors used a set of 550 real case medical images obtained from 50 patients of the Regional Hospital in Zielona Góra. The nuclei were isolated from other objects in the images using a hybrid segmentation method based on adaptive thresholding and kmeans clustering. Described texture features were then extracted and used in the classification procedure. Classification was performed using KNN classifier. Obtained results reaching 90% show that presented features are important and may significantly improve computer-aided breast cancer detection based on FNB images

Computer-aided diagnosis of breast cancer using gaussian mixture cytological image segmentation

This paper presents an automatic computer system to breast cancer diagnosis. System was designed to distinguish benign from malignant tumors based on fine needle biopsy microscope images. Studies conducted focus on two different problems, the first concern the extraction of morphometric and colorimetric parameters of nuclei from cytological images and the other concentrate on breast cancer classification. In order to extract the nuclei features, segmentation procedure that integrates results of adaptive thresholding and Gaussian mixture clustering was implemented. Next, tumors were classified using four different classification methods: k–nearest neighbors, naive Bayes, decision trees and classifiers ensemble. Diagnostic accuracy obtained for conducted experiments varies according to different classification methods and fluctuates up to 98% for quasi optimal subset of features. All computational experiments were carried out using microscope images collected from 25 benign and 25 malignant lesions cases

Activity of aspartate aminotransferase and alanine aminotransferase within winter triticale seedlings infested by grain aphid (Sitobion avenae F.)

Amino acid level is well known indicator of plant resistance to aphids. Our earlier studies showed that grain aphid (Sitobion avenae F.) infestation caused changes in the activity of the enzymes connected with amino acid biosynthesis and the transformation to defensive secondary metabolites within triticale tissues. However, there are not data on the significance of aminotransferases in these processes. The aim of our study was the quantification of changes in the activity of aspartate aminotransferase (AspAT) and alanine aminotransferase (AlaAT) in winter triticale seedlings caused by the feeding of the grain aphid. The study results showed that aphid feeding caused an increase in AlaAT activity and a decrease in AspAT activity within tissues of the triticale. The induced mechanisms of the triticale resistance to the grain aphid are discussed