Paraneoplastic syndrome in squamous cell carcinoma: which substance causes hypercalcemia?

Prepare for the NBME Form 10 Step 2 Test. Utilize flashcards and multiple choice questions, with hints and explanations for each. Ace your exam preparation!

Multiple Choice

Paraneoplastic syndrome in squamous cell carcinoma: which substance causes hypercalcemia?

Explanation:
Paraneoplastic hypercalcemia in squamous cell carcinoma is caused by secretion of PTH-related peptide. PTHrP acts on the same receptors as parathyroid hormone, stimulating osteoclast-mediated bone resorption and increasing renal calcium reabsorption, which raises serum calcium. Because calcium is high, endogenous PTH is suppressed, differentiating this from true PTH-mediated hypercalcemia. Calcitonin would lower calcium, and while true PTH could raise calcium, tumors like squamous cell carcinoma typically produce PTHrP rather than PTH. EPO is unrelated to calcium homeostasis.

Paraneoplastic hypercalcemia in squamous cell carcinoma is caused by secretion of PTH-related peptide. PTHrP acts on the same receptors as parathyroid hormone, stimulating osteoclast-mediated bone resorption and increasing renal calcium reabsorption, which raises serum calcium. Because calcium is high, endogenous PTH is suppressed, differentiating this from true PTH-mediated hypercalcemia. Calcitonin would lower calcium, and while true PTH could raise calcium, tumors like squamous cell carcinoma typically produce PTHrP rather than PTH. EPO is unrelated to calcium homeostasis.

More Multiple Choice Questions
Subscribe

Get the latest from Passetra

You can unsubscribe at any time. Read our privacy policy