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 types. There are three main types of skin cancer . The most serious is melanoma. Like all body tissues our skin is made up of cells: basal cells, squamous cells and melanocytes. Skin cancer types are named after the skin cell in which the cancer develops: basal cell carcinoma, squamous cell carcinoma and melanoma. Carcinoma is another word for cancer. Basal cell and squamous cell carcinomas are often grouped together and called âcommon' skin cancers.