Answer:
Cancer is characterized by uncontrolled growth and division of certain body tissues, so forming a tumor. A tumor results from uncontrolled growth of cells but all tumors are not cancerous.Based on their spread tumors are classified as benign and malignant. A benign tumor remains confined to the particular organ and do not spread to other parts as these are enclosed in a sheath of connective tissue.Malignant tumors grow slowly during the latent stage but soon they start growing faster and start effecting the normal functioning of surrounding tissue. This stage becomes the metastatic stage and the cells from the tumors metastasize i.e. they break from the tumor and migrate to other body organs through the blood or lymph.
Early detection of cancer is necessary because in later stages it becomes incurable most of the time, the most frequently used method is biopsy, Endoscopy, DNA probe analysis radio-logical techniques etc.
