Low pretreatment serum concentration of vitamin D at breast cancer diagnosis in postmenopausal women

Abstract

Objective: The aim of the study was to evaluate the rate of and risk factors for low pretreatment vitamin D (VitD) levels in postmenopausal breast cancer (BC) women, compared with postmenopausal women without BC. Methods: A cross-sectional clinical study was conducted to compare 209 women with BC (case group) to 418 women without BC (control group), age range: 45 to 75 years. The case group consisted of women diagnosed with BC, amenorrhea ≥12 months, aged ≥45 years, without use of medication or clinical conditions that might interfere with VitD levels. The control group consisted of women with amenorrhea ≥12 months, aged ≥45 years, without BC. The groups were matched for age and time since menopause, at a case: control ratio of 1:2. Serum 25-hydroxyvitamin-D [25(OH)D] concentration was measured in all women 10 to 20 days after BC diagnosis and before the proposed treatment. Serum levels ≥30 ng/mL were defined as sufficient. The Student's t test or gamma distribution, χ2 test, and logistic regression (odds ratio, OR) were used for statistical analysis. Results: The BC group had a higher body mass index (BMI) and higher percentage of obesity than the control group (57.4% vs 40.2%, P < 0.0001). In addition, rates of insufficient (20-29 ng/mL) and deficient (<20 ng/mL) 25(OH)D levels were higher in BC patients than in controls (55.6% vs 49.3%, P = 0.039 and 26.2% vs 20.3%, P = 0.018), respectively. In risk analysis (adjusted for age, time since menopause, and BMI), BC patients had a 1.5-fold higher risk of developing low VitD levels (OR = 1.52, 95% CI, 1.04-2.22, P = 0.029) than women without BC. Conclusions: Postmenopausal women had an increased risk of VitD deficiency at the time of BC diagnosis, associated with a higher rate of obesity, than women of the same age group without cancer.

Effect of Selected Factors on the Serum 25(OH)D Concentration in Women Treated for Breast Cancer

“…In addition, Apoe in a similar group showed that 62% of patients had 25(OH)D concentration below 30 ng/mL [40]. Mechado et al tested 209 Brazilian women after breast cancer treatment and 26.2% had vitamin D deficiency and 55.6% had suboptimal levels [41]. These results confirm several published sets of data about the higher prevalence of vitamin D…”

Vitamin D-Induced Molecular Mechanisms to Potentiate Cancer Therapy and to Reverse Drug-Resistance in Cancer Cells

“…Similar to prostate model, conflicting data are also reported for breast cancer. As largely described, an inverse correlation between high circulating 25(OH)D levels and breast cancer risk [80][81][82][83][84]92,93] has been reported, also confirmed in postmenopausal women [85,86]. Conversely, several studies including meta-analyses of observational and case-control studies did not find any correlation between 25(OH)D levels and breast cancer risk [52,87,88,91,104].…”

“…Several observational studies have shown that circulating levels of 25(OH)D, used as surrogate marker for the evaluation of vitamin D status, may be associated with cancer risk [ 5 , 6 , 56 , 57 , 58 , 59 ] and prognosis [ 6 , 60 , 61 , 62 , 63 , 64 , 65 ]. A strong association between low 25(OH)D circulating levels and colorectal [ 6 , 56 , 60 , 61 , 66 , 67 , 68 , 69 , 70 , 71 , 72 ], prostate [ 59 , 62 , 63 , 73 , 74 , 75 , 76 , 77 , 78 , 79 ] and breast [ 52 , 58 , 80 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 , 90 , 91 , 92 , 93 , 94 ] cancer risk has been reported.…”

The Significance of Vitamin D Status in Breast Cancer: A State of the Science Review

“…Understanding the current evidence may help clinicians discern which patients to screen for vitamin D deficiency or insufficiency. Multiple well‐conducted studies conclude that there is a significant inverse relationship between vitamin D status and breast cancer risk in postmenopausal women . This association is not consistently found in premenopausal women .…”