Vitamin D Levels and Their Relationship to Thyroid Malignancy

Abstract

Objectives: Vitamin D deficiency is endemic in the USA. Vitamin D deficiency has been observed in many cohorts of cancer patients and thought to be a possible risk factor. We sought to compare the 25-hydroxyvitamin D levels between a cohort of patients undergoing completion and total thyroidectomy for benign and malignant thyroid diseases. Methods: A retrospective institutional review board (IRB) approved study with chart review was done at a tertiary referral academic medical center. Data were retrospectively collected on consecutive patients who underwent completion and total thyroidectomy at the University of Arkansas for Medical Sciences between October 2005 and December 2012. Postoperative 25-hydroxyvitamin D levels were collected universally and reported when available. Statistical analysis was performed to determine if vitamin D levels varied based on pathology, categorized as either benign or malignant. Results: A total of 220 total and completion thyroidectomies were performed during the study period. Total thyroidectomy (n = 172) was more common than completion (n = 48). Of these, 166 had vitamin D levels available for analysis: 38 with malignant disease and 128 with benign disease. Average vitamin D levels were 29.8 µg/dl for those with malignant disease versus 28.3 µg/dl for those with benign disease. There was no statistically significant difference in vitamin D levels between those with benign versus malignant pathology in this cohort of patients ( P = 0.81). Conclusions: There is no correlation between perioperative Vitamin D status and pathological findings in patients undergoing completion and total thyroidectomy.