Dividing sarcoma cell. Coloured transmission electron micrograph of a sarcoma cell. Sarcomas are malignant (cancerous) tumours in the body's connective tissues. Connective tissues include bone, skin, and ligaments. The cell is in the metaphase stage of division; its chromosomes (dark blue) are aligning in chromatid pairs along its equatorial plane. The process of cell division is known as mitosis.