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.
Skin Cancer Image Gallery. Skin cancer is by far the most common type of cancer. Nearly all skin cancers can be treated effectively if they are found early, so knowing what to look for is important. There are many types of skin cancer, each of which can look different on the skin. This picture gallery contains some examples of the more common types of skin cancer, as well as some other non-cancerous types of skin growths. But skin cancers can look different from these examples.