This study looked at 25-hydroxyvitamin (25(OH)D) levels in 137 Brazilian women with breast cancer. Overall findings show that 25(OH)D deficiency was prevalent among the cancer patients. This deficiency was linked to poor prognosis parameters (reduced likelihood of recovery, chemoresistance, and metastasis.
Vitamin D deficiency is a common issue around the world and has been linked to type 1 diabetes, multiple sclerosis, rheumatoid arthritis, cancer, and a number of other diseases. 25-hydroxyvitamin (25(OH)D) is used as a standard to examine an individual’s vitamin D status. This paper discusses using the vitamin’s levels to predict the development and progression of breast cancer. This type of cancer is mainly related to female aging and is a heterogenous illness with various types of gene expression (different outcomes). The chronic inflammation and constant changes of breast cancer cells may make them resistant to the antitumor effects of vitamin D and its receptor (together they can regulate expression of genes related to cell growth and death).
Between Feb 2016 and May 2017, 147 women with infiltrative ductal carcinoma were studied. Anyone undergoing vitamin D replacement or diagnosed with a different type of cancer was excluded from the study. Blood and tumor samples were collected from the 147 participants. Tumors were placed into four categories based on immunohistochemistry (antibodies used to check for certain antigens). 70 healthy women (no cancer and no vitamin D replacement) were used as a control group. Participants were between the ages of 32 and 88.
25(OH)D testing was performed and used to estimate overall vitamin D status. A chemiluminescence kit was for this step of the study. Healthy serum samples with known vitamin levels were used to determine the kits’ precision (over 90% as stated by manufacturer).
25(OH)D levels for the cancer patients ranged from 4-29.1ng/mL, with a median of 22.0ng/mL. 25(OH)D levels for the healthy control group ranged from 8.8-48.9ng/mL, with a median of 25.6ng/mL. “Plasmatic 25(OH)D was significantly reduced in breast cancer patients in relation to healthy controls…”
Patients with lymphonodal invasion of the tumor cells tended to have lower 25(OH)D levels (vs those without lymphonodal invasion). Patients who developed chemoresistance 6 months after starting chemotherapy also showed lower 25(OH)D levels. Patients with metastasis identified during later follow ups showed lower vitamin levels during diagnosis. Patients still alive after 2 years showed higher vitamin levels than those that died. Overall outcomes were observed and categories were made based on prognosis. This grouping showed that poor prognosis was linked to lower levels of 25(OD)H.
Discussion This study suggests that vitamin D may help prevent the development of breast cancer, which is why reduced levels may occur during its formation. Such a conclusion is consistent with the fact that groups closer to the Equator (higher vitamin D production due to sun exposure) have reported lower levels of breast cancer. Overall, chemoresistance, metastasis, and poorer prognosis (lymph node spreading and death) are all linked to low vitamin D levels.