Cancer is type of disease caused by irregular, uncontrollable growth of blood cells in bone marrow. The process of generating three main blood cells including pallets, red and white blood cells, is started from a progenitor cell called as blast. Blast generates a considerable number of immature cells which are developed affected by differentiation factors. If any interruption occurs during this process, leukemia may be initiated. 
Diagnosis of leukemia is performed at hospitals or medical centers by examination of the blood tissue smeared across a slide and under a microscope by a pathologist. Processing the digital images of blood cells, in order to improve the quality of the image or highlighting the malicious segments of the image, is important in early stages of the disease. 
There are four types of leukemia consisting acute or chronic and myeloid or lymphocytic. Acute lymphocytic (or lymphoblastic) leukemia (ALL) is concentrated in this study. ALL is caused by continuous generation of immature, malignant lymphocytes in bone marrow which are speeded by blood circulation to other organs. 
In this research, fuzzy C-means (FCM) algorithm is applied to blood digital images for clustering purpose, neural networks for feature selection and Genetic Algorithm (GA) for optimization. This model diagnoses ALL at early stages and categorizes it into three morphological subcategories (i.e., L1, L2, and L3).
For performance evaluation of the proposed method, 38 samples of patients with ALL were collected. It was performed on 68 microscopic images in terms of 15 features and yielded to higher percentage of sensitivity, specificity, and accuracy for 10 out of 15 features. The proposed method was compared to three recent methods. The evaluations showed that the sensitivity, specificity and accuracy reached to 85.15%, 98.17% and 96.53%, respectively.