Time-course pattern of blood 25-hydroxycholecalciferol is a significant predictor of survival outcome in metastatic colorectal cancer: a clinical practice-based study

Neoplasma. 2015;62(6):958-65. doi: 10.4149/neo_2015_116.


Vitamin D deficiency has been implicated in the epidemiology of common malignancies including colorectal cancer. We studied consecutive blood levels of 25-hydroxycholecalciferol (25-OHD) in relation to other clinical and laboratory variables in metastatic colorectal cancer patients to ascertain whether their variations may be prognostic or predictive parameters of survival outcomes. Eighty four patients treated with first-line oxaliplatin-based chemotherapy with or without bevacizumab were included. The patients were enrolled on the intent-to-treat basis considering their performance status, comorbidities and laboratory parameters to be medically apt for intensive chemotherapy. Overall survival and progression-free survival were selected as the primary outcomes. Progression free survival and overall survival medians were 15.4 months and 41.2 months, respectively. The cut-off levels of 40 nmol/l for 25-OHD and 11 µg/l for first CEA were identified to be clinical decision levels stratifying patients to the respective prognostic groups. We found that the most consistent outcome predictors were i) any patient surgery, ii) CEA and, independently, iii) time-related blood levels of 25-OHD. We confirmed fundamental and consistent vitamin D deficiency in metastatic colorectal cancer. We demonstrated that all patients with at least one blood level above 40 nmol/l versus all below this cut-off showed profound differences in their disease outcomes. The primary disease stage or time to metastatic stage did not influence the predictive power of blood 25-OHD levels, implying that the time-course pattern of 25-OHD but not the first single measurement may be an independent prognostic factor.

Keywords: colorectal cancer; outcome predictors.; vitamin D.