- Higher post-operative 25-hydroxyvitamin D (25-OHD) levels are associated with better overall survival (OS) in patients with colorectal cancer (CRC).
- No association was observed between pre-operative 25-OHD levels and OS.
Why this matters
- Vitamin D may help to predict survival outcome in CRC.
- Currently, it is unclear what is the most valuable timepoint of blood sampling to determine the association of vitamin D with survival in CRC.
- Study included 515 patients with CRC American Joint Committee on Cancer (AJCC) stages I-III who underwent surgery.
- Patients were divided into pre-operative (n=286; 1 day before surgery) and post-operative (n=229; 8 days after surgery) cohorts according to the time when blood samples were collected for 25-OHD measurement.
- Funding: Cancer Research UK.
- Among 515 patients with CRC, median 25-OHD concentration was 36.7 (interquartile range [IQR], 21.0-55.5) nmoL/L and follow-up duration was 5.9 (IQR, 4.9-6.8) years.
- Overall median survival time for patients who died during follow-up was 2.4 (IQR, 1.1-3.7) years, and for stages I-III was 3.5 (IQR, 2.8-4.7), 2.5 (IQR, 1.1-3.8) and 1.9 (IQR, 1.1-3.3) years, respectively.
- Pre- vs post-operative cohorts did not differ in age, sex, 25-OHD, AJCC stage and localisation of tumour.
- After adjustment for confounders, higher post-operative 25-OHD (>50 nmol/L) level was associated with better OS (HR, 0.53; P=.006), but not pre-operative 25-OHD level (HR, 1.11; P=.646).
- Study evaluated only OS of patients with CRC.