Abstract
Calcitriol-mediated hypercalcemia has been reported in malignant lymphomas and granulomatous diseases but not in lung carcinoma. We describe a patient with squamous cell lung carcinoma with hypercalcemia and elevated calcitriol levels. A 60-year-old Caucasian male patient with stage IIIB squamous cell lung cancer developed hypercalcemia at 14.8 mg/dL two years after receiving chemotherapy and radiotherapy where labs showed a serum intact PTH: 7 pg/mL, PTHrP: 30 pmol/L, 1,25-hydroxyvitamin D (calcitriol): 76 pg/mL, and 25-hydroxyvitamin D levels: <4 ng/mL. Calcitriol levels were elevated despite undetectable 25-hydroxyvitamin D levels. There are no reported lung cancer cases with elevated calcitriol as an etiology of hypercalcemia. We believe that the elevated calcitriol levels in this case were due to a PTHrP-independent mechanism, possibly from either ectopic production of calcitriol in tumor cells or from increased activity of 1-alpha hydroxylase in the same cells. The patient died before the effects of prednisone therapy could be assessed. Studies are needed to investigate the cellular source of calcitriol and its role in hypercalcemia in patients with lung cancer.
Highlights
Calcitriol-mediated hypercalcemia has been reported in malignant lymphomas, both Hodgkin’s and non-Hodgkin’s types [1,2,3,4,5], and diseases involving granulomatous pathology such as sarcoidosis and tuberculosis [6, 7], but not in lung carcinoma
We report here one exceptional case of a patient with squamous cell lung carcinoma with hypercalcemia and elevated PTHrP and calcitriol levels
There are no reported cases of hypercalcemia in squamous cell lung carcinoma associated with elevated calcitriol levels and PTHrP at the same time
Summary
Calcitriol-mediated hypercalcemia has been reported in malignant lymphomas, both Hodgkin’s and non-Hodgkin’s types [1,2,3,4,5], and diseases involving granulomatous pathology such as sarcoidosis and tuberculosis [6, 7], but not in lung carcinoma. Dysregulated calcitriol production is a very rare occurrence in patients with hypercalcemia associated with solid tumors, where suppressed serum calcitriol levels are characteristic. To date, lung carcinoma has not been associated with hypercalcemia from ectopic calcitriol production. We report here one exceptional case of a patient with squamous cell lung carcinoma with hypercalcemia and elevated PTHrP and calcitriol levels
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
