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Plasma 25-Hydroxyvitamin D Levels and Survival in Patients with Advanced or Metastatic Colorectal Cancer: Findings from CALGB/SWOG 80405 (Alliance).
Yuan, C, Sato, K, Hollis, BW, Zhang, S, Niedzwiecki, D, Ou, FS, Chang, IW, O'Neil, BH, Innocenti, F, Lenz, HJ, et al
Clinical cancer research : an official journal of the American Association for Cancer Research. 2019;(24):7497-7505
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Abstract
PURPOSE Previous studies have suggested that higher circulating 25-hydroxyvitamin D [25(OH)D] levels are associated with decreased colorectal cancer risk and improved survival. However, the influence of vitamin D status on disease progression and patient survival remains largely unknown for patients with advanced or metastatic colorectal cancer. EXPERIMENTAL DESIGN We prospectively collected blood samples in 1,041 patients with previously untreated advanced or metastatic colorectal cancer participating in a randomized phase III clinical trial of first-line chemotherapy plus biologic therapy. We examined the association of baseline plasma 25(OH)D levels with overall survival (OS) and progression-free survival (PFS). Cox proportional hazards models were used to calculate hazard ratios (HRs) and confidence intervals (CIs), adjusted for prognostic factors and confounders. RESULTS At study entry, 63% of patients were vitamin D deficient (<20 ng/mL) and 31% were vitamin D insufficient (20-<30 ng/mL). Higher 25(OH)D levels were associated with an improvement in OS and PFS (P trend = 0.0009 and 0.03, respectively). Compared with patients in the bottom quintile of 25(OH)D (≤10.8 ng/mL), those in the top quintile (≥24.1 ng/mL) had a multivariable-adjusted HR of 0.66 (95% CI, 0.53-0.83) for OS and 0.81 (95% CI, 0.66-1.00) for PFS. The improved survival associated with higher 25(OH)D levels was consistent across patient subgroups of prognostic patient and tumor characteristics. CONCLUSIONS In this large cohort of patients with advanced or metastatic colorectal cancer, higher plasma 25(OH)D levels were associated with improved OS and PFS. Clinical trials assessing the benefit of vitamin D supplementation in patients with colorectal cancer are warranted.
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Vitamin A and Breast Cancer Survival: A Systematic Review and Meta-analysis.
He, J, Gu, Y, Zhang, S
Clinical breast cancer. 2018;(6):e1389-e1400
Abstract
BACKGROUND The association between vitamin A intake and breast cancer survival has been inconsistent. We conducted a systemic review and meta-analysis to summarize the results on the association between dietary or supplement vitamin A and its derivatives and breast cancer-specific survival and overall survival (OS). MATERIALS AND METHODS A comprehensive search of PubMed and EMBASE was performed from inception to January 31, 2018. The summary hazard ratios and 95% confidence intervals were estimated using a random effects model. RESULTS Ten studies (8 cohort, 1 clinical trial, and 1 of pooled studies), with 19,450 breast cancer cases, were included in the meta-analysis. The dietary intake of β-carotene was significantly associated with improved breast cancer OS, with a summary hazard ratio of 0.70 (95% confidence interval, 0.50-0.99; I2 = 37.5%) for the highest versus lowest intake and 0.93 (95% confidence interval, 0.88-0.99; I2 = 38.7%) per 1200 μg/day increment of intake when assessing diet before diagnosis. Meta-regression analysis showed that adjustment for body mass index was a modified factor for the association between the intake of β-carotene and breast cancer OS (P = .013). However, the intake of other vitamin A derivatives (eg, α-carotene, β-cryptoxanthin, lycopene, retinol, lutein) had no effect on breast cancer prognosis when assessing diet before and after the diagnosis. CONCLUSION Our findings suggest limited evidence for the significantly inverse association between the prediagnosis dietary intake of β-carotene and OS among women with breast cancer. However, the intake of other vitamin A derivatives was not significantly associated with survival.