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.

Los feocromocitomas y paragangliomas son tumores raros que se originan en las células cromafines. Tienen un amplio espectro clínico que va desde el hallazgo incidental hasta manifestaciones por la producción exagerada de catecolaminas. El diagnóstico bioquímico se realiza mediante medición de metanefrinas libres en plasma. El tratamiento ideal es la escisión quirúrgica completa previo bloqueo de receptores α y β adrenérgicos. En caso de enfermedad metastásica, las opciones de tratamiento sistémico actuales son limitadas y con escasa tasa de respuesta. Está en investigación el uso de antiangiogénicos.

Introducción: Se ha reportado una asociación entre los niveles altos de vitamina B12 y la ocurrencia de múltiples enfermedades. Objetivo: describir las características clínicas de pacientes hospitalizados con hipervitaminemia B12, así como la tasa de mortalidad a un año. Materiales y métodos: estudio observacional retrospectivo realizado en 93 pacientes con hipervitaminemia B12 atendidos en el Hospital Universitario San Ignacio, en Bogotá Colombia entre 2013 y 2020. Los datos se describen utilizando medidas de tendencia central y de dispersión. Se realizaron análisis bivariados (prueba t de dos colas no pareada, prueba de chi-cuadrado o prueba U de Mann-Whitney según el tipo de variable) para determinar diferencias entre los pacientes con niveles altos de B12 y aquellos con niveles muy altos. Resultados: La mediana de edad fue 68 años y el 62.36% de los pacientes eran hombres. El 41.93% de los participantes tenía dos o más comorbilidades asociadas con la hipervitaminemia B12. Además, en 86.02% el nivel de vitamina B12 no fue interpretado como anormal por el médico tratante. Se encontraron diferencias significativas en el antecedente de tabaquismo (p = 0.043) y la presencia de lupus eritematoso sistémico (p = 0.012) entre los pacientes con niveles de B12 altos y aquellos con niveles muy altos. Finalmente, la tasa de mortalidad a 1 año fue de 59.13%. Conclusión: la tasa de mortalidad a un año fue alta y un elevado porcentaje de pacientes tenía al menos dos comorbilidades asociadas a la hipervitaminemia B12. Además, en la mayoría de los participantes, el médico tratante no interpretó correctamente el nivel elevado de esta vitamina. Introduction: An association between high B12 levels and the occurrence of multiple diseases has been reported. Objective: To describe the clinical characteristics of inpatients with B12 hypervitaminosis, as well as their 1-year mortality rate. Materials and methods: Retrospective observational study conducted in 93 patients with elevated B12 levels treated at the Hospital Universitario San Ignacio, in Bogotá (Colombia) between 2013 and 2020. Data are described using measures of central tendency and measures of dispersion. Bivariate analyses were performed (unpaired two-samples t-test, chi-square test or Mann-Whitney U test depending on the type of variable) to determine differences between patients with high B12 levels and those with very high levels. Results: Participant’s median age was 68 years, 62.36% were male and 41.93% had two or more B12 hypervitaminosis related comorbidities. In addition, in 86.02% of the patients, vitamin B12 level was not interpreted as abnormal by the treating physician. Significant differences were found between patients with high B12 levels and those with very high levels in terms of history of smoking (p= 0.043) and the presence of systemic lupus erythematosus (p= 0.012). Finally, the 1-year mortality rate was 59.13%. Conclusion: the 1-year mortality rate was high and a high percentage of patients had at least two comorbidities that were associated with high B12 levels. In addition, in most of the participants, the treating physician did not correctly interpret the elevated level of this vitamin.

Objective: The aim of this study was to evaluate survival in patients with COVID-19 and cancer, and to find factors associated with early mortality. Methods: Retrospective cohort derived from a registry of a referral center in Bogotá. Survival was analyzed according to the type of neoplasm using Kaplan–Meier method. A cox regression was performed to look for factors associated to higher risk of death. Results: Two hundred fifty-four patients were included with cancer and COVID-19, most of whom were women (median age 68 years; range 19–97). Cardiovascular comorbidities were frequent. Patients with hematologic neoplasms had higher survival than those with solid neoplasms (log-rank test, p = 0.024). C-reactive protein levels (hazard ratio 1.02; 95% confidence interval 1.00–1.03, p = 0.025), Charlson’s comorbidity index (hazard ratio 1.15; 95% confidence interval 1.06–1.26, p = 0.004) and respiratory failure (hazard ratio 4.83; 95% confidence interval 2.47–9.44, p = <0.001) were significantly associated with higher mortality. No interaction between active anticancer therapy and mortality was observed. Conclusion: In contrast to other reports, survival was worse in patients with solid tumors than in those with hematologic neoplasms. Increased C-reactive protein, Charlson’s comorbidity index and respiratory failure were associated with higher in-hospital mortality. This study reveals the complex impact of cancer and its treatment on COVID-19 outcomes, highlighting the persistent risks to cancer patients. It emphasizes monitoring C-reactive protein levels, comorbidities, and respiratory failure as key indicators of poor prognosis. Furthermore, we provide new insights into the differential impact of COVID-19 on cancer patients with solid organ versus hematologic neoplasms.