Strength of the Association of Elevated Vitamin B12 and Solid Cancers: An Adjusted Case-Control Study

Elevated Vitamin B12, Risk of Cancer, and Mortality: A Systematic Review

Vitamin B12 (B12) is a molecule involved in several biological. Abnormally high levels are frequently found, but their causes can be multiple, and consequences have not been clearly elucidated. The objective of this review was to summarize the current evidence on the associations of elevated B12 and the development of cancer, and all-cause mortality in adults. Six references looking at mortality and seven looking at cancer risk were included. The evidence suggests an association between elevated B12 with a higher risk of cancer, with risk ratios ranging 1,88 to 5,9. There was less consistent evidence linking vitamin B12 and mortality.

Diagnosis, Treatment and Long-Term Management of Vitamin B12 Deficiency in Adults: A Delphi Expert Consensus

Background/Objectives: Vitamin B12 deficiency can cause variable symptoms, which may be irreversible if not diagnosed and treated in a timely manner. We aimed to develop a widely accepted expert consensus to guide the practice of diagnosing and treating B12 deficiency. Methods: We conducted a scoping review of the literature published in PubMed since January 2003. Data were used to design a two-round Delphi survey to study the level of consensus among 42 experts. Results: The panelists agreed on the need for educational and organizational changes in the current medical practices for diagnosing and treating B12 deficiency. Recognition of clinical symptoms should receive the highest priority in establishing the diagnosis. There is agreement that the serum B12 concentration is useful as a screening marker and methylmalonic acid or homocysteine can support the diagnosis. Patient lifestyle, disease history, and medications can provide clues to the cause of B12 deficiency. Regardless of the cause of the deficiency, initial treatment with parenteral B12 was regarded as the first choice for patients with acute and severe manifestations of B12 deficiency. The use of high-dose oral B12 at different frequencies may be considered for long-term treatment. Prophylactic B12 supplementation should be considered for specific high-risk groups. Conclusions: There is a consensus that clinical symptoms need to receive more attention in establishing the diagnosis of B12 deficiency. B12 laboratory markers can support the diagnosis. The severity of clinical symptoms, the causes of B12 deficiency, and the treatment goals govern decisions regarding the route and dose of B12 therapy.

Association between Elevated Plasma Vitamin B12 and Short-Term Mortality in Elderly Patients Hospitalized in an Internal Medicine Unit

Background

The prognostic value of vitamin B12 blood levels remains controversial. An association between elevated vitamin B12 and mortality has been reported, particularly among elderly patients with cancers and liver or blood diseases. The present study explored the relationship between mortality and elevated vitamin B12 levels in a population of unscheduled inpatients in an internal medicine unit.

Methods

This retrospective observational analysis was conducted between August 2014 and December 2018. We compared 165 patients with elevated plasma vitamin B12 levels (>600 pmol/l) with a random sample of 165 patients with normal B12 levels who were hospitalized during the same period. Demographic, clinical, and biological characteristics were assessed during hospitalization. The primary endpoint was all-cause death at 1 year.

Results

Patients with elevated B12 were younger, with a lower body mass index and lower plasma albumin than those with normal B12 (75 ± 16 years vs 79 ± 13 years, p = 0.047; 23 ± 5 vs 26 ± 7 kg/m2, p  <  0.001; and 33 ± 5 vs 35 ± 5 g/l, p  <  0.001, respectively). The prevalence of auto-immune disease and referral from an intensive care unit was higher among patients with elevated B12 (11% vs 5%, p = 0.043 and 36% vs 10%, p  <  0.001, respectively). After 1 year of follow-up, 64 (39%) patients with elevated B12 had died compared to 43 (26%) patients with normal B12 (p = 0.018). Multivariate analysis using the Cox proportional hazards regression model adjusted for age, gender, body mass index, intensive care unit hospitalization, albumin level, and the presence of solid cancer or autoimmune disease revealed elevated B12 to be associated with a significant risk of death in the first year of follow-up (hazard ratio: 1.71 [1.08-2.7], p = 0.022).

Conclusion

Elevated B12 is an early warning indicator of increased short-term mortality, such as independently of age, cancer, or comorbidities, in patients hospitalized in an internal medicine department.

High cobalamin levels as a five-year risk predictor for developing hematological cancer

BACKGROUND

A high cobalamin level has been related to non-malignant diseases (mainly liver diseases, alcoholism, and renal diseases) and cancer (hematological malignancies and solid cancers such as liver and stomach cancer). However, a previous high level of cobalamin and the implications in the possible development of cancer is still unclear. The main aim of this study was to describe if a previous high cobalamin level is a determinant in the future development of cancer in five years of follow-up. The secondary objective was to determine any differences between cancer groups.

METHODS

A retrospective study was performed. Two databases were employed. The first one included all patients who had a determination of cobalamin in a routine blood test during the year 2010 (a total of 44,166 patients). The second one showed every patient who was admitted to the reference hospital, Hospital Clinico Universitario de Valladolid, during the following five years. Finally, a number of 6710 patients was included. Both databases belong to the medical records of the Hospital Data Surveillance System and are completely validated. Multivariate logistic regression analyses were employed to evaluate the association between cobalamin levels and the appearance of cancer (total and in each subgroup). All analyses were performed using IBM SPSS 24 software (IBM Corp., Armonk, NY, USA).

RESULTS

The sample studied showed a clear association between the risk of hematological cancer and a previous high Cbl level. This relationship was higher among patients with the highest levels (over 779 pmol/L), showing almost two times more risk for development of hematological malignance within 5 years in the multivariate analysis (OR: 1.975, 95% CI: 1.056-3.697, P=0.033). Hematological malignancies were mostly diagnosed within the first three years (86.6%), showing a similar percentage in those three years. There was no association between this previous level and the development of any other type of cancer.

CONCLUSIONS

Our study shows that a high cobalamin plasma level (hypervitaminosis) is associated with the development of hematologic cancer within five years after the measurement. The clinical implication of these findings, together with the clinical suspicion, reinforces the necessity of carrying out specific screening hematological tests in patients with not justified elevated plasma cobalamin levels. New prospective and multicenter studies are necessary to validate these results.

Diagnostic and Therapeutic Perspectives Associated to Cobalamin-Dependent Metabolism and Transcobalamins’ Synthesis in Solid Cancers

Cobalamin or vitamin B12 (B12) is a cofactor for methionine synthase and methylmalonyl-CoA mutase, two enzymes implicated in key pathways for cell proliferation: methylation, purine synthesis, succinylation and ATP production. Ensuring these functions in cancer cells therefore requires important cobalamin needs and its uptake through the transcobalamin II receptor (TCII-R). Thus, both the TCII-R and the cobalamin-dependent metabolic pathways constitute promising therapeutic targets to inhibit cancer development. However, the link between cobalamin and solid cancers is not limited to cellular metabolism, as it also involves the circulating transcobalamins I and II (TCI or haptocorrin and TCII) carrier proteins, encoded by TCN1 and TCN2, respectively. In this respect, elevations of B12, TCI and TCII concentrations in plasma are associated with cancer onset and relapse, and with the presence of metastases and worse prognosis. In addition, TCN1 and TCN2 overexpressions are associated with chemoresistance and a proliferative phenotype, respectively. Here we review the involvement of cobalamin and transcobalamins in cancer diagnosis and prognosis, and as potential therapeutic targets. We further detail the relationship between cobalamin-dependent metabolic pathways in cancer cells and the transcobalamins’ abundancies in plasma and tumors, to ultimately hypothesize screening and therapeutic strategies linking these aspects.

The Controversial Role of HCY and Vitamin B Deficiency in Cardiovascular Diseases

Plasma homocysteine (HCY) is an established risk factor for cardiovascular disease CVD and stroke. However, more than two decades of intensive research activities has failed to demonstrate that Hcy lowering through B-vitamin supplementation results in a reduction in CVD risk. Therefore, doubts about a causal involvement of hyperhomocysteinemia (HHcy) and B-vitamin deficiencies in atherosclerosis persist. Existing evidence indicates that HHcy increases oxidative stress, causes endoplasmatic reticulum (ER) stress, alters DNA methylation and, thus, modulates the expression of numerous pathogenic and protective genes. Moreover, Hcy can bind directly to proteins, which can change protein function and impact the intracellular redox state. As most mechanistic evidence is derived from experimental studies with rather artificial settings, the relevance of these results in humans remains a matter of debate. Recently, it has also been proposed that HHcy and B-vitamin deficiencies may promote CVD through accelerated telomere shortening and telomere dysfunction. This review provides a critical overview of the existing literature regarding the role of HHcy and B-vitamin deficiencies in CVD. At present, the CVD risk associated with HHcy and B vitamins is not effectively actionable. Therefore, routine screening for HHcy in CVD patients is of limited value. However, B-vitamin depletion is rather common among the elderly, and in such cases existing deficiencies should be corrected. While Hcy-lowering with high doses of B vitamins has no beneficial effects in secondary CVD prevention, the role of Hcy in primary disease prevention is insufficiently studied. Therefore, more intervention and experimental studies are needed to address existing gaps in knowledge.

Chronic Non-infectious Osteomyelitis Mimicking Scurvy as the Presenting Sign of Crohn's Disease: Case Report

Chronic non-infectious osteomyelitis (CNO) is a rare, inflammatory process associated with pediatric inflammatory bowel disease (IBD). Signs and symptoms of CNO parallel scurvy, a nutritional deficiency that can affect children with autism spectrum disorder (ASD). This is the first report of a child initially thought to have scurvy, then subsequently diagnosed with CNO as the presenting manifestation of Crohn's disease. This case enhances the literature elucidating extra-intestinal manifestations of IBD and pediatric nutritional deficiencies.

Persistent elevation of plasma vitamin B12 is strongly associated with solid cancer

Elevated plasma vitamin B12 has been associated with solid cancers, based on a single B12 measurement. We evaluated the incidence of solid cancers following B12 measurement in patients with persistent elevated B12, compared to patients without elevated B12 and to patients with non-persistent elevated B12. The study population included patients with at least two plasma B12 measurements without already known elevated-B12-related causes. Patients with elevated plasma B12 (≥ 1000 ng/L) at first measurement (n = 344) were matched for age and sex with patients having 2 normal B12 measurements (< 1000 ng/L) (NN group, n = 344). The patients with elevated plasma B12 at first measurement were split into 2 groups, according to the presence (EE group, n = 144) or the absence (EN group, n = 200) of persistent elevated plasma B12 at second measurement. We compared the cancer-free survival during 60 months between the groups after adjustment for the other elevated-B12-related causes in a survival competing risk model. Compared to the NN group, a persistent elevated plasma B12 ≥ 1000 ng/mL was strongly associated with the occurrence of solid cancer (HR 5.90 [95% CI 2.79-12.45], p < 0.001), contrary to non-persistent plasma B12 elevation (p = 0.29). These results could help to select patients in whom the screening for solid cancers would be of interest.

Is There a Carcinogenic Risk Attached to Vitamin B12 Deficient Diets and What Should We Do About It? Reviewing the Facts

The number of individuals partaking in veganism has increased sharply in the last decade. Therefore, it is critical to look at the implications of vegan diets for public health. Although there are multiple health benefits of a vegan diet, studies have also linked the diet with deficiencies in various micronutrients. This study focuses on vitamin B12, because of its critical role in DNA synthesis and methylation. In light of these connections, a critical review of recent scientific literature is conducted to understand the effects of a B12 deficient diet on the genome and epigenome, and whether it can give rise to cancer. It is observed that a B12 deficiency leads to increased uracil misincorporation, leading to impaired DNA synthesis and genomic instability. The deficiency also leads to global hypomethylation of DNA, a hallmark of early carcinogenesis. The findings of this study highlight the need for increased awareness among vegans to ensure adequate B12 intake through supplementation or consumption of fortified products as a preventative measure. Additionally, the biofortification of staple crops and an improved version of fermented products with increased B12 content can be developed when inadequate intake seems otherwise inevitable.

Serum folate and vitamin B12 levels in cutaneous melanoma

BACKGROUND

Vitamin B12 and folate are the major micronutrients that play significant roles in DNA synthesis. Epidemiological studies and clinical evidences displayed alterations in serum concentrations folate and of vitamin B12 in various human malignancies, yet their roles in patients with melanoma have yet to be understood.

OBJECTIVE

To assess circulating vitamin B12 and folate concentrations of patients with melanoma and compare them with other malignant tumors and healthy subjects.

METHODS

A total of 98 skin melanoma cases from university clinic were enrolled into the study. Serum vitamin B12 and folate concentrations were analyzed by electrochemiluminescence binding assay.

RESULTS

Circulating levels of vitamin B12 in patients with melanoma were similar compared with other malignancies and healthy controls (P > .05). However, melanoma cases had significantly lower serum folate concentrations than healthy control group (P = .04). Melanoma patients with metastatic disease (P = .001) and with short history of disease (P = .05), and those who had active diseases in course of the study (P = .04) had low serum folate concentrations.

CONCLUSION

Serum levels of folate were found significantly lower in melanoma cases, and this association was stronger for patients with metastatic melanoma; however, no such association was found between melanoma and serum vitamin B12 levels.

Evolution of plasma vitamin B12 in patients with solid cancers during curative versus supportive care

INTRODUCTION

The direction of the causal link between solid cancers and elevated plasma vitamin B₁₂ (B₁₂) remains uncertain.

METHODS

We retrospectively included patients having two B₁₂ measurements with a B₁₂ initially ≥ 1000 ng/l and a solid cancer diagnosed between the measurements. Patients were included in the Curative or Supportive group according to their treatments.

RESULTS

B₁₂ changes over time differed between groups (p = 0.001): +157.4 ng/l/month in the Supportive care group versus -171.6 ng/l/month in the Curative care group.

CONCLUSIONS

The decrease of plasma B₁₂ in cases of curative care could suggest that this B₁₂ elevation is secondary to solid cancers.