Hypercalcemia in the setting of squamous cell carcinoma esophagus is mainly due to:
Hypercalcemia may occur in the absence of osseous metastases in squamous cell carcinoma esophagus, probably from parathormone-related peptide secreted by tumor cells. Ref:Harrison,E-18,P-765
Bone metastasis
Calcitonin excess
Parathormone excess
Parathormone related peptide secretion