P88 | Clinical relevance of vitamin B12 in hospitalized cancer patients

Background: Vitamin B12 impairment is common in cancer patients due to several clinical and therapeutic causes, but data regarding their prevalence and significance in this setting are lacking.Methods: We retrospectively enrolled patients hospitalized at our Medical Oncology ward (2017-2022). Plasma B12 levels in pg/ml were stratified as Very Low(VL<200), Low(L200-300), Normal(N300-813) or High(H>813). We collected demographic and clinical data and fitted univariate and multivariate analyses for factors affecting B12 levels.Results: We enrolled 788 patients, B12 level were VL in 14.09% cases, L in 19.42%, N in 49.37% and H in 17.13%. At univariate analysis, females had higher B12 levels compared to males, a negative correlation between B12 and age, folates, albumin, prealbumin total protein was observed and, conversely, vitamin B12 correlated positively with folates(p<0.0001). B12 distribution directly correlated to ECOG-PS levels(p<0.0001) and was higher in advanced compared to early-stage patients, as well as in those who had liver failure. The highest median value was found in breast cancer patients while the lowest in colorectal and gastric cancer. Multivariate analysis confirms the increased probability of H vs. VL B12 in hypoproteinemia, hypoalbuminemia and ECOG PS≥2. Conclusions: To our knowledge, this is the first study investigating B12 levels in a wide group of cancer patients; our data suggest that increased B12 is associated to an impaired clinical status, while in early stage patients B12 deficiency is of concern and may negatively affect the overall outcomes.