A 65 years old male diagnosed by biopsy a case of lung carcinoma, with paraneoplastic syndrome and increased PTH. Probable cause is-
Parathyroid
Parathyroid related peptide
Calcitonin
Calcitonin related peptide
Hypercalcemia is seen in squamous cell carcinoma of lung. The causal mechanism is the production of calcemic humoral substances, most impoantly parathyroid hormone-related protein ( PTHRP) . It has sone biological action similar to PTH. Several other factors like IL-1, TGF, TNF and dihydroxy vitamin D have also been implicated ( Pathologic basis of Disease, 8 th edition)
General pathology