What is Parathyroid Hormone-Related Protein?
This substance, abbreviated PTH-rP, is produced by numerous body tissues and has actions similar to those of parathyroid hormone. It is a normal substance in the body; however, some tumors produce it in high amounts. When PTH-rP is in such high amounts, blood calcium becomes dangerously high. Detecting PTH-rP is a sign that a cancer is afoot somewhere in the body. What Causes Hypercalcemia? Given the feedback system described, the list is rather short: • A tumor excessively producing PTH-rP. Such tumors include: lymphoma, anal sac carcinoma, mammary tumors, and multiple myeloma. It is possible for other tumors to secrete PTH-rP in high amounts but it is rare. The common tumors should be sought first. Lymphoma (lymphatic cancer) is the most common cause of elevated calcium. • Parathyroid gland tumor secreting PTH. • Kidney failure (altering the calcium and phosphorus balance). It should be noted that kidney failure causes hypercalcemia and hypercalcemia causes kidney failure. It will be
