PTH controls calcium and phosphorus levels in the blood. PTH is made by the parathyroid glands, which are four pea-sized glands that lie behind the thyroid gland. If the blood calcium level is too low, the parathyroid glands release more PTH.
Skin cancer is a cancer of the cells in the outermost layer of skin, called the epidermis. The epidermis itself has three layers: an upper and middle layer made up of squamous cells, and a bottom layer made up of melanocytes and basal cells.
Types of skin cancer. Skin cancer is an abnormal growth of skin cells. It most often develops on areas of the skin exposed to the sunâs rays. Skin cancer affects people of all colors and races, although those with light skin who sunburn easily have a higher risk.