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What is A 65 years old male diagnosed by biopsy a case of lung carcinoma, with paraneoplastic syndrome and increased PTH. Probable cause is- and explain in detail?
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)