The hormonal burden in CCAs is reflected in a complex constellation of interplays such as the galanin system, exposure to sex hormone therapy, interferences with vitamin D system, etc., while humoral hypercalcaemia of malignancy, despite rare, has been reported due to PTHrP over-production in addition with other elements such a G-CSF, fibroblast growth factor receptor positivity, or even procalcitonin. The gene discussed is PTHLH; the disease is Hypercalcemia.