Light micrograph of a papillary thyroid cancer. Papillary thyroid cancer is the most common type of thyroid cancer. It is characterised by nuclei (round to oval dark purple structures) that are enlarged, have grooves, are more cleared out and often overlap, in addition to other microscopic features. Haematoxylin and eosin stained tissue section. Magnification: x400 when printed at 10cm wide.